IALA 10 eNAVIGATION AND EMERGING

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e – NAVIGATION AND EMERGING TECHNOLOGIES / e – NAVIGATION ET TECHNOLOGIES EMERGENTES
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04/02/10
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PROCEEDINGS
couvdblepage.pdf
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proceedings8.eps
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e‐NAVIGATION AND EMERGING TECHNOLOGIES e‐NAVIGATION ET TECHNOLOGIES EMERGENTES CONTENTS Virtual Aid to Navigation – What are we waiting for?? ................................................ 3
Michael Skov, Danish Maritime Safety Authority (DaMSA), Denmark .......................................... 3
Navigating eLoran : challenges and the way forward................................................ 10
Sally Basker and Paul Williams, General Lighthouse Authorities of UK and Ireland..................... 10
Portable Pilot Unit: A challenging e‐Navigation application for Germany’s most frequented port approach River Elbe ....................................................................... 20
Capt. Dietmar Seidel, Federal Waterways and Shipping Administration Directorate North, Germany ..................................................................................................................................... 20
National Aids‐to‐Navigation Authorities Acting as a “Trusted Third‐Party Marine Information Provider” ............................................................................................ 33
Christian Forst, Federal Waterways and Shipping Administration, and Prof. Jens Froese, Jacobs University Bremen, Germany .......................................................................................................33
Intelligent Information Systems for e‐Navigation .................................................... 45
N. Ward, General Lighthouse Authorities of the United Kingdom and Ireland ............................ 45
Application of Three‐Dimensional Simulation System to the Placement and Management of Aids to Navigation......................................................................... 50
Guowei CHEN, Shanghai Maritime Safety Administration Aids to Navigation Department, P.R. of China........................................................................................................................................... 50
New Solid State Frontier on Radar Technologies...................................................... 61
Felicia Amato, Michele Fiorini, Sergio Gallone and Giovanni Golino, Rome, Italy........................ 61
New Technology Radars and the Future of Racons ................................................... 68
N. Ward & M. Bransby, General Lighthouse Authorities, Research & Radio Navigation Directorate, UK, and R. McCabe & C. Day, Commissioners of Irish Lights, Ireland .......................................... 68
A Next Generation Solid State, Fully Coherent, Frequency Diversity and Time Diversity Radar with Software Defined Functionality ............................................................. 74
By Jens Chr. Pedersen, Director, Product Portfolio & Innovation, Radar Systems, Terma A/S, Denmark ..................................................................................................................................... 74
Four‐Season Lighted Buoy Development ................................................................ 86
Développement d’une bouée lumineuse quatre saisons............................................... 86
Richard Moore, Canadian Coast Guard – Garde côtière canadienne ‐ Canada............................... 86
The Recapitalisation of the GLA’s Marine Differential GPS Network .........................101
A Grant & N. Ward, The General Lighthouse Authorities of the United Kingdom and Ireland, UK, A Cran, The Northern Lighthouse Board, UK, R Tomkins, Trinity House, UK and S Doyle, The Commissioners of Irish Lights, Ireland........................................................................................101
The Use of an Under Keel Clearance Management System as an Aid to Navigation in the Torres Strait .........................................................................................................107
Mahesh Alimchandani, Australian Maritime Safety Authority, Australia....................................107
Birds Plague Laser Control and WiFi Technologies Applied to Environmental Control Improvement in Port Areas................................................................................... 118
Enrique Bernabeu, La Maquinista Valenciana SA, Spain.............................................................118
Assessment of shoal bank movements via Earth Observation, related to re‐positioning needs for Aids‐to‐Navigation.................................................................................124
Michelle De Voy, Martin Bransby, Alan Grant and Sally Basker, The General Lighthouse Authorities of the United Kingdom and Ireland, Ian Thomas and Gordon Keyte, British National Space Centre, UK ...................................................................................................................... 124
Experiment and Research on Using Ultra Capacitor as Power of AtoN ......................135
Aids to Navigation Department of Shanghai China MSA............................................................135
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 2 Virtual Aid to Navigation – What are we waiting for?? Michael Skov, Danish Maritime Safety Authority (DaMSA), Denmark ABSTRACT
“Denmark replaces all traditional Aid to Navigation with virtual Aid to Navigation!”
This statement is a provocation, I know, and it is not likely to be true in near future. We have a lot of
unsolved challenges such as integrated bridge system ability to display virtual AIS as an AtoN symbol.
Furthermore it is important to realize that shipping as modern as it seems to be is very conservative and
changes are not implemented over night.
Virtual AIS as an AtoN is just another tool in our AtoN toolbox and it can be used by it self successfully in
some cases and together with other aids in other cases such as marking of fairways in certain areas. It is
important to take up the challenge with the gaps in display requirements, symbology and recognition by
mariners. And use virtual AIS in combination with safety related messages for emergency response
purposes.
RESUME
“Le Danemark remplace toutes ses aides traditionnelles par des aides à la navigation virtuelles!”
Cette déclaration est une provocation, je le sais, et elle n’est pas près d’être vraie dans le futur proche. Il y
a beaucoup de problèmes non résolus, tels qu’un système de passerelle intégré permettant d’afficher un
AIS virtuel comme un symbole d’aide à la navigation. En outre, il faut réaliser que la navigation, aussi
moderne qu’elle apparaît, reste très conservatrice et les changements ne se font pas en une nuit.
L’AIS virtuel en tant qu’aide à la navigation n’est rien qu’un autre outil dans notre boîte d’aides à la
navigation, et il peut-être utilisé avec succès dans certains cas seul ou dans d’autres cas avec d’autres
aides, comme pour le balisage de chenaux dans certaines zones. Il est important de relever le défi,
combler les vides qui existent pour l’affichage, la symbologie et la reconnaissance par les marins. Et utiliser
l’AIS virtuel avec les messages de sécurité pour répondre aux situations d’urgence.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 3 INTRODUCTION
“Denmark replaces all traditional Aid to Navigation
with virtual Aid to Navigation!”
This could very well be an announcement in Danish
Notices to Mariners followed by same headline in
Danish media in the near future. We are in fact ready
with the technology and by replacing traditional Aid to
Navigation with virtual Aid to Navigation we can cut
costs in maintenance of traditional Aid to Navigation.
And still aiming at our vision to have the safest
waters in the world to navigate.
Replacement of all traditional Aid to Navigation with
virtual Aid to Navigation. Can it be done in reality? Do
we have the technology needed for this task? And do
we want to do this? I will try to answer these
questions in my presentation.
BACKGROUND
AIS was installed in ships as early as 2000 and since 31 December 2004 it has been mandatory to fit AIS
aboard all ships of 300 gross tonnage and upwards engaged on international voyages, cargo ships of 500
gross tonnage and upwards not engaged on international voyages and all passenger ships irrespective of
size.
Land organizations were soon to follow as they saw the possibility for gathering information of ships sailing
in their waters. So they began building up national land based AIS networks and establishing AIS data
bases containing historical data as well as on-line data. This data can then by analyzed for a lot of
purposes such as water way planning, aids to navigation planning etc.
DaMSA uses AIS data for many purposes such as accident investigation, AIS statistics, virtual AIS Aid to
Navigation and AIS messages. This presentation will give some examples of this.
The presentation will focus on the pros and cons of virtual Aid to Navigation, and with interesting
illustrations show some of the benefits with virtual Aid to Navigation and some examples of operational use
in Danish waters. With background in the present status for e-navigation the future needs of Aid to
Navigation will be analyzed.
EXAMPLES OF OPERATIONAL USE
In 2004, DaMSA initiated the development of a shore based AIS network in Danish waters. As part of the
requirement for the network, it was foreseen that the system should include capabilities for transmitting
Synthetic AIS AtoN signals to supplement and highlight existing physical AtoNs, or virtual AIS AtoN signals
to highlight new obstacles or areas of danger. It was also anticipated, that AIS AtoN technology should be
used on certain off shore AtoNs for monitoring and control purposes.
Emergency wreck marking
In February 2007 a former Russian whiskey class submarine under tow to Bangkok was lost by the tug
near ’Jyske Rev’ off the northwest coast of Denmark.
A navigational warning was issued as usual, and DaMSA notified its buoy tender to locate the wreck and
deploy relevant markers. However, due to the bad weather and the time it would take locate and mark the
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 4 wreck, it was decided to deploy a virtual AtoN named ‘New Wreck, depth unknown’, and to automatically
alert vessels to the relevant navigational warning by an addressed safety related AIS message, when
entering the area near the wreck.
It was generally agreed, that this kind of usage of AIS AtoN technology proved to be quick and easy to
deploy, and once the shore infrastructure exists, such AtoN services can be provided at almost no extra
cost.
Not much operational experience was gathered in this instance – however it was noted that at least one
vessel replied “well received” to the AIS Safety Related Message alerting the vessel to the navigational
warning.
When the cargo vessel OMER N capsized in
October 2007 in the busy strait Femer Belt
between Denmark and Germany, the wreck ended
up slightly closer to shore, not far from the busy
transit route, with part of the wreck just above
water.
DaMSA shortly after deployed a virtual AIS AtoN,
marking the new wreck even before the buoy
tender could reach the position. An automatic
message service was deployed, using AIS safety
related messages to alert mariners of the new
danger ahead, by the text ‘New Wreck’ – and a
reference to the navigational warning issued.
The vessel changed course after receiving the alert regarding new wreck via AIS Safety Related Message We configured the service to alert only those
vessels, who were taking the shorter path close to the wreck, while not distracting those vessels, who were
following the transit route at a safe distance.
At this incident, it was observed that there was a documented effect of the message service – several
vessels were noted who actually altered their course to go closer to the marked transit route, away from the
wreck, shortly after receiving the AIS alert.
Emergency wreck marking and similar marking of new or temporary obstacles is considered to be one of
the strongest cases for using AIS AtoN technology.
It was however also noted, that most vessels did not seem to react to the new danger, until they were close
enough to see the wreck visually – or see the physical mark, that was deployed shortly after.
At this point, DaMSA was contacted by MARNAV (Marstal Navigational Education Centre), who had
observed, that the virtual AIS AtoN marking the wreck was visible on some of their display systems, but not
on others. MARNAV had contacted the manufactureres, Furuno, Transas and Maris, regarding the issue,
and the manufactureres had different explanations as to why they could not display the AIS AtoN target.
There are no test standards for displyal equipment, that state anything on how display systems should be
tested, regarding handling AIS AtoN targets, so this is really up to the manufacturer how to handle – or
whether to handle at all.
We investigated the issue futher, and found that the danish pilots were also unable to see the virtual AIS
AtoN target on their portable pilots displays, as were the operators at the danish MRCC on their displays.
We concluded, that due to the lack of display requirements and test standards for displaying AIS AtoNs, the
effect of deploying virtual AIS AtoNs was much less, than the effect of the AIS Safety related Message
service, since we could not relay on AIS AtoN signals to be displayed to mariners, even if they had a
graphical display capable of displaying AIS information, however the AIS text messages would be available
on the MKD of a class A AIS station.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 5 At DaMSA this made us wonder how many vessels were in fact able to detect and display an AIS AtoN
signal. We initiated a process and asked the Danish pilots whether they could detect virtual AIS AtoN target
or not whenever passing an area where AIS AtoN were deployed.
Emergency obstacle marking
Quite similar to the Emergency Wreck Marking incidents described above, the AIS AtoN and AIS Message
Service systems were taken into use, when a lighthouse on Skanseodde, marking the approach to
Fredericia port, was damaged in January 2008, and the remains of the lighthouse constituted a dangerous
submerged obstacle.
While the virtual AIS AtoN could be deployed quickly, and continue to highlight the temporary marker that
was deployed, the message service was considered to be the most beneficial instrument, to alert only
those who needed to know.
VIRTUAL AIS WAYPOINTS
In July 2006, a traffic separation scheme (TSS)
was established in the Bornholmsgat between
Sweden and the Danish island Bornholm as well
as a TSS North of Rügen between Germany
and Sweden.
With AIS, we could prove that traffic patterns
certainly changed into a more orderly flow.
However, over a period of 2 years, 4 vessels
grounded on the west coast of Bornholm, as a
result of drunk, sleeping or otherwise inattentive
mariners, who simply forgot to turn to the northeast, when entering the TSS Bornholmsgat from
west or south-west.
In fact the OOW was fast a sleep for more than
4 hours before waking up a ground just South of
Roenne harbour. The ship was on auto pilot and
it luckily missed the port entrance.
DaMSA considered various options for
addressing the issue, and for a trial period 2
AIS AtoNs: Creating waypoints without creating obstacles? waypoints were created in the form of virtual AIS
AtoN, indicating the points where vessels should turn. The hope was that without creating obstacles,
virtual waypoints might help the mariners plan and execute their navigation. We were well aware of this not
addressing the above mentioned problems but it could raise a flag.
Information was given to mariners by Navigational Warnings and Danish Notices to Mariners.
During this trial, pilots were asked, when boarding vessels in the area, to note whether these AIS AtoNs
could be detected by the equipment onboard various vessels.
The trial intentionally sparked a debate on what the role of virtual AIS or other electronic Marine Aids to
Navigation could and should be.
Concerns were raised by Danish, Swedish and German administrations regarding recognition of such
objects by mariners. The experiences gathered include the realization, that the role of a new Marine Aids to
Navigation technology must be understood by Aids to Navigation authorities and mariners alike.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 6 If all the technological components involved in
providing, communicating and visualizing /
displaying such electronic AtoNs are not
developed in a holistic, coherent process, the
benefits of such a flexible technology is not
likely to be reached.
Also the risks associated with providing Aids to
Navigation partly or entirely through electronic
means should be elaborated and managed.
These kinds of trials are considered useful by
DaMSA, to raise debate on the use of AIS
AtoNs for such purposes, in order to identify
the gaps that need to be filled within the
framework of the e-Navigation process. After
15 weeks the trial was discontinued.
VIRTUAL AIS AS AN ATON
In the southern part of the Sound between
Sweden and Denmark lies the dredged
channel Drogden which can be very difficult to
navigate. The current is often strong and can
be difficult to predict and the traffic flow around
the L/H Drogden is unregulated.
This has often resulted in close passages of vessels and unfortunate approaches of the dredged channel
from the south, especially with South-Westerly wind and North going current.
Furthermore meeting of large vessel in the dredged channel has resulted in a lot of near miss situations
and striking of marking. The red light buoy no 16 was hit several times by vessels and it was decided to
move it as far North as possible. This happened in December 2007.
In order to improve the approach to the dredged channel further another trial with virtual AIS as an AtoN
was initiated in 2008. Our aim was also to gain more experience with AIS as an AtoN.
Four additional virtual AIS AtoN were deployed to mark a ‘funnel’ at the entrance to the Southern part of the
channel, without creating obstacles to navigation.
Operators at a nearby facility were planning a survey interview for vessels approaching the area, regarding
the use of differentially corrected positioning systems, and questions regarding the capability of detecting
the virtual AIS AtoN on the vessels navigation systems were added to the survey.
Shortly after the deployment of the four virtual AIS AtoN operators from the Sound VTS centre nearby
requested us to remove the names of the virtual AIS AtoN as they were obscuring the picture of making a
“funneleffect”.
However, the AIS AtoN technology does not contain any means of indicating, where the name of an AIS
AtoN should be displayed in a chart display. This is currently up to each manufacturer to decide where and
how this information is displayed to the user of the display system.
SYNTHETIC AIS AS AN ATON ON OFFSHORE STRUCTURES
AIS AtoNs have been taken into operational use, as additional means to highlight offshore structures in
Danish waters. In other parts of the North Sea, AIS AtoNs are also used for this purpose.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 7 In February 2009 more than 30 Oil and Gas drilling
platforms were marked in the Danish sector of the North
Sea, using synthetic AIS AtoN, transmitting the signals from
two AIS base stations in the region.
We consider the use of AIS AtoN to be a useful
supplementary means of marking off shore structures.
How should we use AIS AtoN to highlight one main drilling
platform with 4 ‘satellite platforms’ at a distance from each
other? Well, if we look at what should be presented to a
mariner in his display, this depends on the zoom level, just
like electronic chart objects. At a ‘Coastal’ scale, it would at
most be relevant to display one object, indicating the
existence of an oilfield or wind farm in question, in order not
to obscure the display by having several objects on top of
each other. At an ‘Approach’ or ‘Harbour’ scale, it might
however be relevant to see each individual offshore
platform, or the corners of the area of a wind farm. This is
not possible at present.
The experiences gathered in this case raises a number of
questions, and generally indicate, that the role of AIS AtoN
technology in comparison with charted AtoN is largely
unexplored. Should AIS (or other electronic) AtoN only be
used for highlighting single large scale objects, or new /
temporary objects? Should there be a formal link between
AIS (or other electronic) AtoN objects, and an associated
charted object? These issues need to be addressed in the
context of e-Navigation, if AIS or other electronic means of
providing AtoN are to be useful technologies in the future.
FUTURE USE
The AIS AtoN technology could be a useful tool for us as an AtoN provider if the issues of display
technology, availability of graphical displays and recognition by mariners are all addressed.
An AIS AtoN station or a synthetic AIS AtoN signal may be useful for highlighting important objects at a
distance beyond even radar range; just like racon.
The full benefit AIS AtoN technology is not likely to be available to mariners, unless display standards
support such features.
If performance standards were agreed upon SOLAS vessels could have the capability to make use of AIS
(or other electronic) AtoN without creating obstructions for others. Furthermore AIS AtoN is easy to deploy.
In certain environments such as the Arctic area it is not realistic to deploy traditional AtoN. The opening of
Arctic waters to shipping transit between the Pacific and the Atlantic oceans via the North-East or the
North-West Passage is now a fact due to climate changes. These routes save fuel and maybe even time.
However providing traditional AtoN in such regions is difficult and expensive.
CONCLUSIONS
The possibility to mix traditional physical AtoN technology with virtual AtoN may prove to be a feasible
option for providing more cost effective and dynamic AtoN services. However, with the current gaps in
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 8 display requirements, symbology and recognition by mariners, providing such a service will have little or no
effect.
AIS AtoN technology - physical and virtual – is the first step into an electronic AtoN concept and we are
now in the fortunate situation that the e-Navigation process over the next few years may benefit from the
experiences from virtual AIS AtoN around the world.
AIS AtoN are not really of much practical use, unless they can be displayed in a graphical radar or chart
display.
AIS technology has already proven to be a successful supplement to traditional AtoN technology, in terms
of rapid deployment and issuing of safety related text messages.
If only few can see an electronic AtoN service provided, Maritime Safety Administrations cannot rely on
such services – and will thus not provide such services. However, if no one provides such a service, no one
will build equipment that displays such services, and mariners will not recognize or be trained to recognize
such services.
It will not be possible to replace all AtoN with virtual AtoN in near future which is shooting down my initial
statement.
RECOMMENDATIONS
•
•
Provide an electronic AtoN service even for a limited number of users
Secure the conspicuity of AtoN used by mixing all kinds of AtoN including virtual AIS; it is just
another tool in our AtoN toolbox
• Use virtual AIS in areas were providing of traditional AtoN is difficult and expensive
• Take up the challenge with the gaps in display requirements, symbology and recognition by
mariners
• Use virtual AIS in combination with safety related messages for emergency response purposes.
And finally do not forget the following by Piet Hein:
“When technology becomes the master, we reach disaster faster!”
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 9 Navigating eLoran : challenges and the way forward Sally Basker and Paul Williams, General Lighthouse Authorities of UK and Ireland BIOGRAPHY
Dr Sally Basker is the Director of Research and Radionavigation for the General Lighthouse Authorities of
the United Kingdom and Ireland. Dr Basker holds a B.Eng degree in Civil Engineering and a Ph.D in satellite
geodesy from the University of Nottingham. Dr Basker is a Fellow of the Royal Institute of Navigation, a
Member of the US Institute of Navigation, and the President of the International Loran Association.
Dr Paul Williams is a Principal Development Engineer with the Research and Radionavigation Directorate of
The General Lighthouse Authorities of the UK and Ireland, based at Trinity House in Harwich, England. As the
technical lead of the GLA's eLoran Work Programme, he is involved in planning the GLAs’ maritime eLoran
trials and works on a wide range of eLoran projects. He holds BSc and PhD degrees in Electronic Engineering
from the University of Wales, is a Chartered Engineer, an Associate Fellow of the Royal Institute of Navigation
and is a board member of the International Loran Association.
ABSTRACT
e-Navigation will bring a step-change to maritime operations. As currently envisaged, the primary system
will be based on Global Navigation Satellite Systems (GNSS), enhanced communications, electronic charts
and integrated displays, with backup provided by radar and physical aids to navigation – lighthouses and
buoys.
GNSS will become so reliable that mariners will not expect it to fail. They will become even less familiar
with the use of backup systems and may simply be unable to cope safely with a sudden GNSS failure.
Though the probability of losing GNSS may be low, the consequential impact could be very high. We need
an independent, dissimilar and complementary backup to GNSS that keeps e-Navigation running, taking
over seamlessly when GNSS fails. The General Lighthouse Authorities of the UK & Ireland (GLA), in
common with the US and other national administrations, believe that eLoran is that backup.
Since 2003, the GLAs have been pioneering the introduction of eLoran in Europe: they have deployed a
new transmitter station; conducted successful GPS jamming and eLoran trials; and worked with European
colleagues to promote eLoran’s additional, non-maritime benefits. The GLAs have identified their strategic
requirement: a robust, resilient and cost-effective positioning, navigation and timing system, based on
GNSS and eLoran. The GLAs’ eLoran strategy is: to extend their current trials; to continue building a
European consensus in favour of eLoran; and to prepare for the introduction of eLoran services in 2013.
When the GLAs and their European partners deliver this strategy, it will result in the provision of a Europewide eLoran service that will secure the broad benefits that we all enjoy from GNSS and enable new
applications and services. An essential part of this process will be to form and cement relationships with
Loran operators in other regions, in particular FERNS and North America.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 10 RÉSUMÉ
L’e-Navigation va apporter un changement radical dans les opérations maritimes. Tel qu’on l’envisage
actuellement le système premier sera basé sur les systèmes mondiaux de navigation par satellites (GNSS),
des communications améliorées, des cartes marines électroniques et des affichages intégrés, le système
de secours étant assuré par le radar, les aides à la navigation physiques – phares et bouées.
Le GNSS deviendra tellement fiable que les marins ne s’attendront pas à le voir tomber en panne. Ils ne
seront plus familiers de l’utilisation des systèmes de secours et pourraient tout simplement ne pas faire
face à une panne soudaine du GNSS. Bien que l’éventualité de perdre le GNSS soit faible, son impact
serait très important. Nous avons besoin d’un système de secours indépendant, différent et
complémentaire au GNSS, qui maintiendrait l’e-Navigation et prendrait le relais en cas de panne. Le
Groupement des autorités de phares du Royaume-Uni et d’Irlande (GLA), de même que les administrations
des Etats-Unis et d’autres pays, pense que l’eLoran est ce système de secours.
Depuis 2003 les GLAs ont pris la tête de l’introduction de l’eLoran en Europe : ils ont déployé une nouvelle
station émettrice, conduit avec succès des essais de panne de GPS et d’eLoran, et travaillé avec leurs
collègues européens pour promouvoir les avantages complémentaires, non maritimes, de l’eLoran. Les
GLAs ont défini leur exigence stratégique : un système de localisation, de navigation et de synchronisation
robuste, stable et rentable, basé sur le GNSS et l’eLoran. La stratégie eLoran des GLAs est la suivante :
étendre les essais en cours ; continuer la construction d’un consensus européen en faveur de l’eLoran ; et
préparer l’arrivée des services eLoran en 2013. Lorsque les GLAs et leurs partenaires européens mettront
cette stratégie en pratique, il en résultera un service eLoran à la taille de l’Europe qui garantira les
avantages que nous apporte le GNSS et permettra de nouvelles applications et de nouveaux services. Une
part essentielle de ce processus consistera à former et cimenter des liens avec les opérateurs de Loran
d’autres région, notamment le FERNS et l’Amérique du Nord.
1. INTRODUCTION
GPS now underpins much of our critical infrastructure including telecommunications, power distribution,
finance, and transport. However, the low-power, high-frequency GPS signals are fragile and vulnerable to
all sorts of intentional and unintentional interference. More satellite systems are not the answer: existing
low-cost jammers are designed to deny the civil and military signals of all Global Navigation Satellite
Systems (GNSS - i.e. GPS, GLONASS, Galileo).
The requirement is for resilient positioning, navigation and timing: it needs to be inherently reliable, secured
against obvious external threats and capable of withstanding some degree of damage.
A single, cross-sector solution that augments GNSS with an independent, dissimilar and complementary
system is best for users: they will benefit from economies of scale to keep equipment costs low; existing
networks - user, technology, business and regulatory - can be exploited; and this will all lead to lower longterm average costs than any other approach.
eLoran is the only candidate that can be deployed in a timely fashion.
This paper presents an overview of eLoran in Section 2. In Section 3, the paper discusses the drivers and
requirements for eLoran. eLoran technology is briefly described in Section 4 before the GLAs’ eLoran trials
in the Orkneys are summarised in Section 5. Finally, future challenges are identified in Section 6.
Tables and figures are provided at the end of the paper.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 11 2. eLORAN OVERVIEW
The International Loran Association provides the following description of Enhanced Loran (eLoran) [7]:
Enhanced Loran is an internationally-standardized positioning, navigation, and timing (PNT) service
for use by many modes of transport and in other applications. It is the latest in the longstanding and
proven series of low-frequency, LOng-RAnge Navigation (LORAN) systems, one that takes full
advantage of 21st century technology.
eLoran meets the accuracy, availability, integrity, and continuity performance requirements for
aviation non-precision instrument approaches, maritime harbour entrance and approach
manoeuvres, land-mobile vehicle navigation, and location-based services, and is a precise source
of time and frequency for applications such as telecommunications.
eLoran is an independent, dissimilar, complement to Global Navigation Satellite Systems (GNSS). It
allows GNSS users to retain the safety, security, and economic benefits of GNSS, even when their
satellite services are disrupted.
Any discussion of the difference between Loran-C and eLoran is complicated because Loran-C has been
modernised at different times and to different extents in different parts of the World. The following
descriptions are provided for clarification [17].
USCG Loran-C
The original version of Loran-C (c. 1960s) based on tube transmitters, SAM
control, ASF look-up tables and hyperbolic navigation, requiring large
numbers of people on site. Typical accuracy: 460m (95%).
Modernised Loran-C
The original version of NELS (c. 1990s) based on solid-state transmitters,
time-of-emission timing, ASF model, hyperbolic or rho-rho navigation, and
requiring very few people on site. Typical accuracy: 100m (95%).
Prototype eLoran
The GLAs’ system (c. 2008) based on modernised Loran-C together with (i)
Eurofix to carry UTC and differential-Loran, (ii) all-in-view navigation, (iii)
precise ASF surveys, and (iii) differential-Loran reference stations for
maritime use. Typical accuracy: 10-20m (95%). Real-time prototype eLoran
has been in operation for two years and is now running continuously.
eLoran
This is the future (c. 2013?) based on prototype eLoran together with (i)
updated station equipment to improve timing stability, (ii) mitigation of
vulnerabilities to ensure high availability, (iii) Eurofix at all stations, and (iv)
modernised control at Brest. Typical accuracy: 10-20m (95%).
It is important to note that all generations of Loran support Stratum 1 frequency for telecommunications.
Prototype eLoran and eLoran support UTC time of day. eLoran will support sub-50ns precise timing.
Each of these generations delivers different levels of performance (Table 1) and so provides different
capabilities in terms of the applications that it supports (Table 2). eLoran is most applicable for 21st century
applications.
3. DRIVERS, REQUIREMENTS & ELORAN
3.1 Driver – GNSS Vulnerability
There is now broad agreement that Global Navigation Satellite Systems (GNSS – e.g. GPS, Galileo,
Glonass, Compass) are vulnerable to unintentional and intentional interference. This includes natural
phenomena, e.g. due to the ionosphere [1].
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 12 The use of GPS jammers, long foreseen in navigation circles, has become a reality as criminals employ
them to overcome tracking systems and steal vehicles [10]. Low-powered jammers are readily available
over the Internet for as little as $150 and can block GPS reception in a vehicle’s vicinity. They can also
block all mobile phone bands used in the area.
Today’s jammers are already configured to jam GPS, Galileo and Glonass civil and military signals
simultaneously on both the L1 and L2 frequencies. It would be trivial to add L5. Some of these jammers are
powerful, radiating 2W on each frequency. This is more powerful than the GPS jammer used by the GLAs
in their jamming trials (Section 3.3).
GNSS performance also suffers from system errors whether from satellite rephrasing, system design, or
system upgrades.
3.2 Driver – Extending GNSS Performance
Extending GNSS performance is also a driver for some eLoran developments. Specifically, ST
Microelectronics [11] is exploring integrated eLoran and GPS at the chip scale to give consumer GNSS
receivers the extreme sensitivity needed to start up deep inside buildings, including concrete underground
carparks.
This translates into a requirement for tight integration at the chip level.
3.3 Case Study – GLA Jamming Trials
The General Lighthouse Authorities have held two sets of GPS jamming trials in 2008 and 2009 to
understand the impact of a loss of GPS on the safety of navigation [20]. The following conclusions have
been drawn.
•
A 1.5W GPS jammer denies GPS for about 30 Kilometres.
•
The precise impact of GPS jamming on a vessel depends on the bridge fit, configuration and level of
system integration.
•
Hazardously Misleading Information (HMI) - GPS jamming can produce HMI with positioning errors
from a few to hundreds of kilometres and velocities of 10kts to 20000kts.
•
DSC / GMDSS – these alarmed when the GPS positioning input was lost. In the worst case, there is
potential for search and rescue agencies to be directed to an incorrect location with obvious safety
consequences.
•
DGPS – this alarmed when the GPS positioning input was lost and had a knock-on effect on the
position reporting on the ECDIS and the AIS.
•
AIS – this alarmed when the GPS positioning input was lost. AIS lost its ability to identify the bearing
and distance of other ships and AIS AtoNs. Other ships and the vessel traffic services perceive the
jammed ship to be in the wrong place.
•
Gyros – these alarmed. The precise impact depends on the GPS / gyro integration.
•
GPS receivers – one was affected to such an extent that it would not track GPS satellites automatically.
The solution was to turn off the receiver for about an hour to force a cold start.
3.4 Requirement – Resilient PNT
Resilient PNT (positioning, navigation and timing) is today’s requirement not just for the maritime sector but
for critical infrastructure (e.g. transport, telecommunications, power distribution, finance, emergency
services etc.) in general [1].
The UK Centre for the Protection of National Infrastructure uses the following definition for resilience [7]:
the equipment and architecture used are inherently reliable, secured against obvious external threats and
capable of withstanding some degree of damage.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 13 O’Rourke [15] states that resilient physical and social systems must be ‘robust, redundant, resourceful and
capable of rapid response’, where:
Robustness:
The inherent strength or resistance in a system to withstand
external demands without degradation or loss of functionality
Redundancy:
System properties that allow for alternate options, choices, and
substitutions under stress
Resourcefulness:
The capacity to mobilize needed resources and services in
emergencies
Rapidity:
The speed with which disruption can be overcome and safety,
services, and financial stability restored
3.5 The Requirement – GNSS Interference Detection and Mitigation
There is also a need for GNSS interference detection and mitigation that is being explored in the US [13]
and UK [5].
In our safety-critical environment this needs to be available on board the ship. There are different ways of
detecting interference. However, interference mitigation needs to ensure that a user’s operation is not
disrupted.
The requirement should be to maintain the user’s concept of operations with a seamless transition from
GNSS to a backup. This is what is really needed for e-Navigation.
An inferior approach would provide a backup that does not maintain the user’s concept of operations and
requires manual intervention.
3.6 The Requirement – a Systemic Backup
Users not only need resilient PNT, they also need it to be cost-effective and so a systemic backup is the
best solution. In this case, systemic means that the backup can be used within many user sectors – air,
maritime, land, telecommunications, critical infrastructure …
Key benefits of a systemic backup include:
•
short-term economies of scale – broad, cross-sector demand will ensure that cost of the systemic
backup is very low. In practice, this means that chip-level integration with GNSS can be achieved swiftly
and the cost to the user is small.
•
linking into existing GNSS networks – these include technology research, product development and
manufacturing, sales and marketing, user networks for retrofitting and regulation.
•
lower long-term average costs – the cost of a systemic backup should always be lower than sectorspecific backups and should decrease over time. On this basis, systemic backups should decrease the
long-term average costs for many stakeholders.
3.7 The Solution - eLoran
At the highest level, the requirement is for resilient PNT (Section 3.4). GNSS will undoubtedly be one of the
sources of PNT. The requirements for a GNSS complement are given below.
The GNSS complement shall:
•
enable resilient PNT for use by critical infrastructure applications including maritime transport.
•
be readily integrated with GNSS at chip-level.
•
support interference detection and mitigation.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 14 •
maintain the user’s concept of operations with a seamless transition to a complement when GNSS is
lost.
•
have the potential to be deployed world-wide.
•
support maritime general navigation applications.
•
be independent of GNSS.
•
be dissimilar in terms of failure modes.
•
provide similar levels of performance as GNSS
eLoran is the only system that can meet all these requirements in a timely fashion and support the
development and implementation of e-Navigation.
4. ELORAN TECHNOLOGY
4.1 Standardisation
eLoran standardisation efforts began in October 2007 with the first meeting of the Radio Technical
Commission for Maritime Services Special Committee-127 (RTCM-SC127). SC-127 was established to
consider the need for the development of standards for eLoran position, navigation and timing (PNT)
system components, including, but not limited to maritime eLoran receivers, and/or combined
GNSS/eLoran receivers. Once such a need was identified the group would develop appropriate RTCM
Standards or Reports addressing performance requirements, technical requirements, and/or test
procedures, with a view to their use for the production of eLoran systems, and as the basis for eventual
IMO, ITU and/or IEC recommendations or standards, as appropriate. The release of a draft RTCM eLoran
Receiver Minimum Performance Standard (MPS) is imminent at the time of writing.
In addition, a draft proposal to revise Resolution A.818 (19), ‘Performance Standards for Shipborne
LORAN-C and CHAYKA Receivers’, has been developed by RTCM SC-127 and the GLAs. This has
recently been submitted to the UK Maritime Coastguard Agency, the UK’s representative on the IMO
Maritime Safety Committee, for comment, review and eventual submission. Following the revision of A.818
would be a submission to the International Electrotechnical Commission (IEC) to establish receiver test
standards.
4.2 Hardware
Two Loran transmitters are now available:
•
Megapulse transmitters are the workhorse of Loran networks worldwide [12]; and
•
A joint venture between UrsaNav [18] and Nautel [14] has produced a more compact solution that has
been tested with 70 ft (20m) tactical antennas.
There are a number of receivers available:
•
Maritime receivers are available from manufacturers including Megapulse (SI-TEX), Reelektronika [16]
and CrossRate Technology [4]. These generally use a crossed-loop H field Loran antenna so that the
receiver also acts as an accurate True North compass and so is useful for driving heads-up displays.
•
Timing receivers are also available from Reelektronika and CrossRate.
•
ST Microelectronics has been experimenting with chip-level integration [11].
Differential-Loran reference stations and ASF Measurement Equipment is available from Reelektronika.
An eLoran simulator is available from Alion [9].
In the UK, the GAARDIAN team is developing a joint GPS / Loran interference detection and mitigation
system to alert service providers and users when there is a potential problem. GAARDIAN is a UK initiative
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 15 that is funded by the Technology Strategy Board, part of the Department for Business, Innovation and Skills
and led by Chronos Technology [5].
5. PERFORMANCE
Researchers worldwide have already shown that eLoran can meet the accuracy, availability, integrity, and
continuity performance requirements for aviation non-precision instrument approaches and maritime
harbour entrance and approach [7].
The GLAs have been developing initial proof of concept systems, and testing them in challenging
environments. One such type of challenging environment is densely packed island regions. For example,
the Finnish Maritime Administration expressed its concerns about the performance of eLoran in the
archipelagos off the southwest coast of Finland.
In response to this challenge the GLAs performed eLoran trials in the Orkney Islands – an archipelago off
the northern coast of Scotland, which is very similar to those archipelagos near Finland [19]. The Orkney
Islands lie some 20km from northeast Scotland in an area of excellent Loran geometry and signal strength
from the stations at Ejde, Vaerlandet and Anthorn (Figure 1).
Three routes were followed on three separate days. The total distance travelled was some 230Nm with a
total steaming time of about 23 hours at 10kts, the biggest trial the GLAs have performed to date.
To establish an eLoran system in the area for the duration of the trials two things were required:
•
A differential-Loran Reference Station
•
A map of signal propagation corrections, (or Loran ASFs) stored within our receiver.
A temporary differential-Loran Reference Station was installed at Kirkwall – the capital city of the Orkney
Islands. Signal propagation maps were derived from the data collected during the performance of the
routes.
The most technically difficult part of the voyage occurred in the Hoy Sound (see Figure 1); a channel with
complex land-sea signal paths. However, we still achieved accuracies of 11m (95%) using eLoran.
These accuracy levels are typical of those realised in widespread trials over the past four years.
Our conclusion so far is that where we have good eLoran transmitter geometry and signal strength, and we
have established a maritime eLoran service, complete with propagation correction maps and differentialLoran, there is no reason why eLoran should not provide close to (if not better than) 10m (95%) positioning
accuracy. Other challenging areas include mountainous terrain and fjords, and we will need to investigate
such areas in the near future. The GLAs have developed the ability to quickly and accurately establish a
temporary eLoran installation for trial purposes, and measure and analyse the system’s performance.
6. CHALLENGES
The main challenge is to ensure that resilient PNT based on GNSS and eLoran is available to support the
introduction of e-Navigation. This is recognised in IALA’s World Wide Radio Navigation Plan [6]:
GNSS (in particular GPS) has become the primary means of navigation in many maritime
applications. However, the vulnerability of GNSS to accidental or deliberate interference is well
known and the need for more than one position input to e-Navigation is recognised.
It is noted that Loran/Chayka is the only wide area terrestrial radio-navigation system currently
available
Members of IALA with Loran/Chayka facilities within their jurisdiction are encouraged to retain them
in operation and make plans to upgrade them to eLoran capability, so that they can form part of the
WWRNP
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 16 A second challenge is to bring together interested parties from around the World to develop an
implementation plan based on a common understanding of user and functional requirements.
7. REFERENCES
[1]
Basker S. GPS Vulnerability. Pres. IALA ad hoc meeting on eLoran, Haugesund, Norway, September
2007.
[2]
Basker, S. Robust and Resilient PNT: Today’s Requirement. Proc CGSIC 49, Savannah, Sept 2009
[3]
Centre for the Protection of National Infrastructure. Good Practice Guide for Resilience in Converged
Networks. May 2009.
[4]
CrossRate Technology. www.crossrate.com
[5]
Curry C. GAARDIAN - A UK Government Funded R&D Project Using eLoran to Investigate GPS
Interference. Proceedings of the 38th Convention of the International Loran Association, Portland,
Maine, October 2009.
[6]
IALA, World Wide Radio Navigation Plan, 2010.
[7]
International Loran Association. Enhanced Loran (eLoran) Definition Document. Version 1.0, October
2007.
[8]
Johnson, G.W., Swaszek, P.F., Hartnett, R. & Nichols, C., Navigating Harbors at High Accuracy
without GPS: eLoran in the United States, Proc. European Navigation Conference ENC-GNSS2007,
Geneva, Switzerland, 2007.
[9]
Johnson, GW. Integrated GPS-eLoran simulator. Proceedings of the 38th Convention of the
International Loran Association, Portland, Maine, October 2009.
[10] Last D. GPS Forensics, Crime & Jamming. 2nd GNSS Vulnerabilities and Solutions Conference, 2-5
September 2009, Baška, Krk Island, Croatia.
[11] Mattos, P.G., GNSS and eLoran Tightly Coupled, Proceedings of the 22nd International Technical
Meeting of the Satellite Division of the Institute of Navigation (ION GNSS 2009), Savannah, GA,
September 2009, pp. 873-880.
[12] Megapulse Technology. www.megapulse.com.
[13] Merrill, J. Update on US Interference Detection and Mitigation Plan (IDM). Proc CGSIC 49, Savannah,
Sept 2009
[14] Nautel. www.nautel.com.
[15] O’Rourke, T.D. Critical Infrastructure, Interdependencies, and Resilience. The Bridge. Vol. 37, No.1.
National Academy of Engineering, 2007.
[16] Reelektronika. www.reelektronika.nl
[17] Research & Radionavigation. Evolution from Loran-C to eLoran. Internal briefing notes, February
2010.
[18] Ursa Navigation. www.ursanav.com.
[19] Williams, P. and Hargreaves, C., eLoran Performance in the Orkney Archipelago, Proceedings of the
38th Convention of the International Loran Association, Portland, Maine, October 2009.
[20] Williams, P., Grant, A., Ward, N. and Basker, S., Reliable GPS: Interference, Jamming and the Case
for eLoran, Proceedings of the Royal Institute of Navigation (RIN) NAV08/ International Loran
Association 37th Annual Meeting, London, 2008.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 17 TABLES AND FIGURES
Table 1 – Performance delivered by different generations of Loran Accuracy (m, 95%)
Integrity
Availability
USCG Loran-C
460
Low
Low
Modernised Loran-C
100
Moderate
Moderate
Prototype eLoran
10-20m
High
Moderate
eLoran
10-20m
High
High
Notes:
1.
Accuracy: The Table shows the approximate value of the absolute accuracy achievable across the specified coverage area by
a receiver that uses ASF corrections. The most demanding accuracy specification met by eLoran is that required for maritime
harbour entrance. eLoran achieves its high accuracy by means of: “all-in-view” receivers that track multiple stations and
employ advanced signal processing; precise ASFs measured in harbour surveys; and real-time differential Loran corrections
generated at reference stations and transmitted over the data channel.
2.
Integrity: The measure of the trust that can be placed in the correctness of the information supplied. It includes the ability of the
system to provide timely warnings to users when the system should not be used for navigation. The most demanding integrity
specification met by eLoran is that required for non-precision aviation instrument approaches. The much higher integrity of
eLoran compared to Loran-C is principally due to the rapidity of its response to system failures. Signals are monitored
continuously and warning messages passed promptly to the receiver via the data channel.
3.
Availability: The percentage of time the services of the system are usable by a navigator within the specified coverage area.
The most demanding availability specification met by eLoran is that required for non-precision aviation instrument approaches.
The much higher availability of eLoran, compared to the earlier versions of Loran, has been achieved by numerous
improvements in the transmitting station infrastructure and operational procedures. Not all of these have been implemented in
Prototype eLoran. The other major contributor to eLoran's high availability is the use of "all-in-view" receivers that track
multiple stations, rather than the 3-station triads of Loran-C.
Table 2 – Applications supported by different generations of Loran Supported Application
USCG
Loran-C
Modernised
Loran-C
Prototype
eLoran
eLoran
3
9
9
9
9
9
Resilient PNT1
2
9
Maritime: Ocean
2
Maritime: Coastal & Harbour
9
Aviation: Non-Precision Approach
9
Stratum 1 Frequency
9
UTC
Precise Timing
Land Mobile
4
Interference Detection & Mitigation
5
9
9
9
9
3
9
9
9
9
9
1.
Notes:
2.
PNT – Positioning Navigation and Timing. Resilient PNT (e.g. based on GNSS + eLoran) is emerging as the requirement in
many sectors. The UK Centre for the Protection of National Infrastructure uses the following definition for resilience: the
equipment and architecture used are inherently reliable, secured against obvious external threats and capable of withstanding
some degree of damage. Prototype eLoran does not yet have full availability due to existing operational procedures.
3.
Maritime requirements based on: International Maritime Organisation Resolution A.953(23) [1].
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 18 4.
Full performance precise timing is not available due to the timing steps used for station synchronisation. Use of frequency
steering in eLoran should enable continuous sub-50ns timing.
5.
20-30m (95%) vehicle accuracy has been obtained in central London in conjunction with map-matching.
6.
Interference Detection and Mitigation (IDM) is increasingly important. The UK’s GAARDIAN project is doing this by comparing
GPS, eLoran and clocks.
Hoy Sound
Figure 1 – The GLAs’ eLoran Orkney Trials 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 19 Portable Pilot Unit: A challenging e‐Navigation application for Germany’s most frequented port approach River Elbe Capt. Dietmar Seidel, Federal Waterways and Shipping Administration Directorate North, Germany ABSTRACT
The river Elbe is Germanys most frequented fairway. Approximate 80.000 vessels p.a., among them a
significant number of Container Megacarriers and deep draught bulkers, use this fairway to reach ports like
Hamburg, Brunsbüttel, Cuxhaven and Stade.
The continuous rise in number of vessels as well as the increase of size of vessels made the anticipation of
additional e-Navigation tools necessary to grant safe and efficient traffic flow. Portable Pilot Units were
considered to be the adequate tool.
The PPU for river Elbe is designed to fit pilots and VTS requirements.
STEP 1: since the Elbe is an estuary with high morphological activity and sedimentation, continuously
updated sounding plans are displayed within an ENC chart, converting the ENC to a bathymetric ENC
(bENC).
STEP 2: up-to-date tidal information will be integrated to enable shipping to be continuously aware of
available water level.
STEP 3: The Under-keel-clearance-management (UKC) module combines the sounding and tidal
information with vessels specific (squatting) characteristics.
STEP 4: the last module will integrate a logistic port planning tool. Passage of vessels shall be optimized
not only in nautical but as well in commercial parameters.
The PPU-Elbe-development and the results so far achieved will be shown as well as the steps still left to go.
RÉSUMÉ
L’Elbe est la voie de navigation la plus fréquentée d’Allemagne: environ 80 000 navires, parmi lesquels un
grand nombre de porte-conteneurs géants et de vraquiers à fort tirant d’eau, utilisent cette voie chaque
année pour rallier les ports de Hambourg, Brunsbüttel, Cuxhaven et Stade.
L’accroissement continu du nombre des navires et de leur taille, laisse prévoir de d’autres outils d’eNavigation seront nécessaires pour garantir un flux de trafic sûr et efficace. Les « unités pilote portables »
(PPU) sont considérées comme un outil adéquat.
Le PPU pour l’Elbe est conçu pour répondre aux besoins du pilote comme de STM.
ETAPE 1 : puisque l’Elbe est un estuaire d’une grande activité morphologique et de sédimentation, des
plans de sondages à jour sont continuellement affichés sur une carte marine électronique, la convertissant
en carte bathymétrique.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 20 ETAPE 2 : une information de marée à jour sera intégrée pour permettre aux marins d’être toujours
informés de la hauteur de l’eau.
ETAPE 3 : un module de gestion de la profondeur d’eau sous la coque (UKC) combine les informations de
sondage et de marée avec les caractéristiques spécifiques du navire.
ETAPE 4 : le dernier module intégrera un outil logistique de planning de port. Le passage des navires en
sera optimisé, non seulement au niveau nautique mais aussi commercial.
Le développement du PPU-Elbe sera montré, de même que les résultats déjà obtenus et les étapes restant
à franchir.
Before getting to the point it is necessary to define an understanding of PPU and explain some basics
about the Elbe. This will be necessary to understand our PPU alignment. Thereafter the chronology of PPU
development is described since this is quite interesting in view of the final solution found.
1. DEFINITION OF PPU
PPU comprehends applications running on a customary notebook on the background of professional
navigation software. These applications deliver additional safety-relevant and estuary specific information
to pilots thus improving quality of pilot advice and producing a quantifiable added-value to safety and
easiness of traffic. According to our understanding PPU has to reflect the special requirements for the
estuary it will be used in.
2. TRAFFIC DEVELOPMENT ON RIVER ELBE AND GENERAL NAUTICAL CONDITIONS
River Elbe is an estuary of abt. 120km length, with dredged areas that are 400m/300m and over the last 10
km 270m wide. Important ports along river Elbe are Cuxhaven, Brunsbüttel, Glückstadt, Stade/Bützfleth
and, of course Hamburg. Additionally several ship yards settled in the region.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 21 Fig. 1 As the gate to and from the Kiel-Canal the area of Brunsbüttel acts as a high sensitive traffic junction.
Currently vessels with a maximum draught of 15,10m are allowed to ride on top of
Fig. 2 Extra Ordinary Large Containerships 2004 until September
2009
800
700
the tide
wave
towards
Hamburg.
700
River Elbe
is as well
the the
500
436
most
Number
400
frequented
estuary in
300
224
Germany
200
as one of
the busiest
100
47
4
in the
0
world.
Sept. 2008
2004
2005
2006
2007
to Sept.
Traffic
2009
consists of
4
47
224
436
700
Number of Vessels
abt.
Year
80.000
vessels
p.a. –excluding small fisherboats and pleasure craft. Among them the quantity of “Extraordinary Large
Vessels” (length > 330m, breadth >45m) is rising disproportionately most of them presently
containercarriers.
600
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 22 In spite of the economical decrease we experienced during the last year, there is a significant increase as
can be seen from Fig. 2.
River Elbe is affected by the tide –tidal range is abt. 3,0 to 3,5m. There is as well a significant
sedimentation i.e. depth variability within a certain range. A scheduled fairway redesign is delayed due to
legal aspects. Nevertheless the “Extraordinary Large Vessels” are scheduled and our aim is, to make their
passage as safe and easy as possible.
Therefore precise navigation information, especially continuously updated charted depths are essential not
only for pilots and as well for the responsible VTS-Centres Cuxhaven and Brunsbüttel.
3. CHRONOLOGY OF PPU DEVELOPMENT
In 2005 we started with an industrial finished PPU-product and soon realized that we choose not an optimal
way. At that time the system was based on a “normal” ENC and included two GPS-antennas and one AISantenna. This means the receiving systems had to be installed prior to use of the PPU-system. It not only
took time to find the right location –sometimes, with those nowadays often existing closed bridge wings, it
was even impossible to install the antennas. Additionaly the whole equipment had to be carried. It´s weight
summed up to 13-15 kg –far too much! The advantages (e.g. rate of turn information) did not compensate
the disadvantages.
Consequently we, the Federal Shipping Administration and Elbe-Pilots, started defining a system suitable
for River Elbe. System data should partly be used for VTS-Centres as well.
Since the additional AIS and GPS antennas created an installation and weight problem, the only way left
was a pilot-plug-based solution. This in turn, we learned, made it necessary to solve “pilot-plug-bugs”. The
suitable tool turned out to be the “Seamate” produced by Mølgaard NetCom A/S, Thistedt, Denmark. It
connects standard computers with the vessels instruments and resolves interface problems reliably. For
example, chart plotter, GPS, speed log, echo sounder or gyro, in fact any instrument transmitting NMEA
and AIS-data, RS232/RS422. The box is very simple to connect to any input signal.
The next step was to find a qualified navigation software. This was, compared to other development steps,
the simplest task. We choose the ORCA Master from 7Cs. Having stepped forward so far, we decided to
use a GPS-mouse and the AIS receiving capability of the seamate integrated as backup solution. Should
the pilot plug become defective for any reason there will be at least a GPS-Signal.
Thereafter we decided that it was not good enough by half to have only exact positions in a conventional
chart showing theoretical available dredged depths. This was the hour of birth for the bathymetric ENC
(bENC). I will discuss that item later on.
Basically, the requirements to hardware, software and handling, discussed and agreed between Federal
Shipping Administration and Elbe-Pilots were described as follows.
4. HARDWARE – BASIC PARAMETERS
•
Customary components
•
Well-known leading manufacturers
•
State of the art technology
•
High reliability
•
Quick and reliable support available
•
High cost efficiency
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 23 5. HARDWARE – USER REQUIREMENTS
•
As low as possible weight
•
Maximum battery capacity
•
High screen resolution
•
Simple and intuitive handling
•
Reliable connectivity to pilot-plug
•
Reliable connectivity to external sensors (AIS, GPS)
•
Recording on external memory
6. APPLICATIONS – USER REQUIREMENTS
•
ENC like chart display
•
Position adequate display of own ship
•
Display of updated morphology
•
Display of AIS-Information
•
Intuitive desktop functions
•
functionoriented operation (e.g. hiding of temporarily not used applications)
•
Simple menue navigation and push button allocation
•
Unmistakable colour display day/dawn/night
•
short start-up
•
Simple, reliable und quick updating
•
Replay function
Before further explaining the bENC I shall at first explain our strategy for PPU development.
7. STRATEGIC OBJECTIVES TO BE ACHIEVED BY PPU OPERATION
BASIC CONDITIONS
First: PPUs (each component) have to generate an added value! This added value must be precise and
measurable! For River Elbe it is a quantifiable gain of safety (more efficient utilisation of traffic area) and a
quantifiable reduction of cost for the so-called radar advisory service by pilots.
Second: PPUs have to fulfil the specific requirements of an estuary! There is no general solution! General
solutions are not the optimum for an estuary!
When we had completed the hardware configuration we discussed and decided the strategy. This was
evolved as follows:
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 24 Step 1: Integration of updated depths into the ENC is the crucial point. It will generate the utmost gain for
the safety and easiness of shipping.
Step 2: Since River Elbe is a tide influenced estuary, the integration of real-time tide gauges was estimated
essential, especially for the tide-constrained shipping. High water levels will widen the areas available for
vessels. These areas should be made visible real-time.
Step 3: Since vessels speed is generating squat and squat is consuming a significant portion of available
depth, we found it essential to find out how vessels squat in constrained waters and started investigations
(still running) on this subject. The consolidated findings will enable us to decide the draught/speed/time
limits we set for tide-constrained shipping. The aim is to grant as much under-keel-clearance (UKC) as for
the safety of shipping necessary but not more because this would be an uneconomical waste of resource.
We want to implement UKC-management!
Step 4: We find it useful to integrate a logistic traffic system that supplies real-time information for example
at what time a berth is available.
8. CREATING THE BATHYMETRIC ENC
At first we had to decide whether to use raster or vector charts. The decision was easy. The advantages of
vector charts are obvious. You can increase detail level without losing clarity of picture.
Raster‐Chart (left) Vector Chart (right) Fig. 3 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 25 Fig.4 is a cutout from a conventional chart. It shows a part of the Elbe entrance (green buoys and cardinal
buoys). The red line is the so-called radar-line, the centre of the dredged area. The dredged area itself is
displayed with the to-be depths –here 15,0m at LAT-level.
Fig. 4 The ENC-Display, here the Elbe area round Cuxhaven is shown, is of course similar. You will note that the
dredged area is displayed with the to-be depths only as well.
Fig. 5 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 26 The industrial finished
PPU-product I mentioned
before showed useful
details but not the
essential depth
information; a part of
Hamburg port is shown
here.
Í Fig. 6 How far to-be depths and
reality are apart from each
other is clearly visible in
Fig. 7. The upper picture
shows a cutout from an
official ENC, the lower
picture shows the relief
with the real depth
structure.
It is clearly visible that the
dredged area is covering the to-be depths, even major depths. Furthermore it is evident that there is
intense southward sedimentation developing in the north towards the dredged area.
Fig. 7 Upper picture of Fig 7 is a cutout of an official ENC – lower picture showes the bathymetric reality 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 27 It was a long way to obtain a bENC -bathymetric data integrated into an official ENC.
Sounding Data was and is permanently collected and processed by Waterways and Shipping bureaus
Hamburg and Cuxhaven. The whole process had to be redesigned. We had to create a Digital Ground
Model (DGM) of the whole River consisting of numerous cells into which the newest local soundings could
be integrated at any time, thus making the whole River-DGM available at any time.
Fig. 8 shows this cell-structure.
Fig. 8 The DGM-data then had to be converted into the so-called S57 format which is used for ENC charting.
Only this conversion made it possible to integrate the DGM-data into an ENC, mariners use for navigation.
The software used is:
FME – Safe Inc.- Conversion of sounding data to S 57 format
ENC Designer – 7Cs- Verification of conversion
ENC Optimizer – 7Cs- Optimizing and Quality Assurance
The problem of different updating cycles bathymetric data ./. ENC was solved this way as well.
The bathymetric data is updated according to sounding activity, whereas the ENC is updated relatively
seldom. If the bathymetric data is only a layer within the ENC the updates can be performed independently
and cellwise. This gives the advantage, not having to update bathymetric date and ENC daily. This would
have created an unnecessary high update-data volume.
The updated depth information is then made available for download on a FTP-server. When logging in a
PPU-unit, an automatic update process is initiated on each PPU unit.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 28 Some work had to be done before. We had to design new sounding plans that contain all necessary
information not more. They had then to fit into an ENC. The design shown in Fig. 9 is obviously not
appropriate. This kind of plan was used by Waterways and Shipping bureau Hamburg before. The blue
area showed the dredged to-be depths and more, the red areas the less than to-be depths.
Fig. 9 The design displayed in Fig. 10 is not suitable as well.
Fig. 10 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 29 The solution achieved is shown in Fig. 11. It contains numbers and colours for depth areas. The numbers
are considered to be enough to allow safe navigation. The colours show areas of certain depth levels so
that at one glance you have an impression which real depths –even more than to-be depths- are available.
Fig. 11 Fig. 12 points out the advantage of real-depth bENC charting. On the left side a cutout from a conventional
ENC is displayed and on the right side the same conventional ENC enriched with the bathymetric data.
Fig. 12 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 30 The advantages of bENC information are obvious. What shall we do with it besides making it available on
the PPU units?
Presently there are two VTS-Centres supervising River Elbe traffic. One is located in Cuxhaven, the other
one in Brunsbüttel. We find it essential that an identical information base is available for pilots as well as for
VTS-Centres. For this reason we shall integrate the bENC information into the VTS screen displays. Both,
pilots and administration are granting the safety and easiness of traffic, working together in different
functions and roles. Precise and identical navigation and river information is essential for both of them.
9. PPU PERSPECTIVES
What´s the status and where do we want to go to?
Step 1: Integration of updated soundings (bENC)
Integration of bathymetric data (bENC) is successfully completed. It will certainly be agreed that it is wise to
have enough trial runs if a complex system is newly redesigned. That´s exactly what we think.
Therefore the following missions need to be accomplished:
•
Testing of hard-/ and software quality and stability,
•
Testing of PPU configuration,
•
Testing of data conversion process, of data integration and
•
Testing updating under daily routine operation.
If this will be completed successfully, and I have no doubt, more PPU units will be installed to be of use
when navigating deep-draught and/or Extraordinary Large Vessels.
Step 2: Integration of real-time tide-gauges
It is not that easy to get real-time tide gauges on board of any vessel i.e. PPU unit approaching River Elbe.
The outer area is too far from shore, creating the problem of non-satellite transmitter coverage for data
transfer. We presently are exploring different solutions. One direction is to explore data transfer alternatives,
the other one is to have numerical tide gauge approximation solutions until reaching transmitter coverage.
Step 3: Integration of UKC-Management System (UKC = Under Keel Clearance)
We have of course squat data for vessels. There had been intense programs of measuring squat
phenomena on different types of vessels during their passage in confined waters. Since vessel design and
typing developed we looked for numerical solutions in cooperation with a classification society. Currently
we are exploring ways to get them optimized, safeguarded for more types of vessels. We feel that
hydraulic-model-testing as well as a hydrodynamic-numerical method will generate precise enough results
and we are confident to achieve these results for the module UKC-management within acceptable time.
Step 4: Integration of logistic traffic system
Logistic systems will be developed. This will still take some time.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 31 10. FINAL LAYOUT
A final display could look as shown in Fig.
13. It´s the graphic display of tide
allowance for deep-draught vessel. The
blue frame is the graphic display of the
limited zone a deep-draught vessel may
navigate in, while on passage to
Hamburg on the tide wave. Of course the
other vessels respectively their AIS
symbols will be displayed as well and, if
selected in the VTS-Centre their graphic
display of tide allowance.
Portable Pilot Units and their design are
no secret science. They only have to
reflect state-of-the-art of science and
technology and be embedded into proper
seamanship. Proper seamanship is the
basis. It will never be unnecessary.
Insofar, Portable Pilot Units are just
another tool. A fascinating one that
opens up a multitude of additional
chances. We should take them.
Capt. Dietmar Seidel
Fig. 13 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 32 National Aids‐to‐Navigation Authorities Acting as a “Trusted Third‐
Party Marine Information Provider” Christian Forst, Federal Waterways and Shipping Administration, and Prof. Jens Froese, Jacobs University Bremen, Germany ABSTRACT
It is normally not possible, to adapt the existing maritime infrastructure to the increasing number and size of
vessels due to long planning processes in due time and in a non resource-consuming way.
Intelligent information and communication technologies show a great potential, in increasing the
effectiveness of the infrastructure if they cover the entire logistics process, including: on board navigation,
waterways and harbour management, terminal management as well as other logistic services provided in
the maritime environment.
Value-added services should be defined and implemented globally. However, developing one global
integrated system can not be the aim, there needs to be freedom for individual solutions, but effective
interoperability of existing and emerging systems allowing for a maximum of freedom concerning
information format and content.
Main prerequisites to implement proper value-added services are the the willingness of all stakeholders to
comprehensively exchange all relevant information throughout the entire logistics process chain and to
develop a coherent process “landscape” to allow easy and consistent allocation of all issues of relevance..
A major obstacle is the variety in combination of tasks, roles and responsibilities through out the
stakeholders. To overcome this heterogeneity a strict process-oriented approach has to be followed.
However, some of the information required will potentially be of commercial sensitivity.
To overcome this challenge national Aids-to-Navigation Authorities (national members of IALA) could act
as a trusted third party information provider. This would result in confidence of shipping and the maritime
industry.
RÉSUMÉ
Il n’est généralement pas possible d’adapter l’infrastructure maritime existante au nombre et à la taille
grandissants des navires, en raison de la longueur du processus dans le temps et des resources
auxquelles il fait appel.
Une information et des technologies de communication intelligentes offrent un fort potentiel, en accroissant
la capacité de l’infrastructure, à condition qu’elles couvrent la totalité du processus logistique, y compris la
navigation à bord, la gestion des voies navigables et des ports, la gestion du terminal, et autres services
offerts dans l’environnement maritime.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 33 Des services à valeur ajoutée devraient être définis et mis en œuvre de façon globale. Cependant on ne
doit pas envisager un système unique intégré, il faut garder la liberté de proposer des solutions
individuelles, mais rechercher une interopérabilité entre systèmes existants ou émergents, afin d’obtenir un
maximum de liberté dans les formats et les contenus de l’information.
Les conditions préalables à la mise en œuvre de services à valeur ajoutée sont la volonté des parties
prenantes d’échanger les informations requises tout au long de la chaîne logistique, et le développement
d’un processus cohérent pour l’attribution aisée de toutes les questions concernées.
L’obstacle majeur est la variété des combinaisons de tâches, de rôles et de responsabilités au sein des
parties prenantes. Pour parer à cette hétérogénéité il convient d’appliquer une approche fondée sur l’idée
du processus.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 34 INTRODUCTION
It is a well agreed scenario, that the number and size of vessels will increase in the future. The present
global economic crisis will be overcome and global trade is the basis for a world-wide peaceful
development and global welfare.
To adapt the existing maritime infrastructure to the increasing demands is due to long planning processes
regularly not possible in due time.
A planning procedure for new infrastructure programs regularly requires 5 years or even longer. As an
example, the last adoption of the river Elbe as approach to the sea-port Hamburg to newer Container
vessel generations took about 10 years.
Container Vessel leaving Port of Hamburg (Source: Hafen Hamburg/M. Lindner) In addition, it has to be taken into consideration, that the public opinion is more and more critical towards
infrastructure projects. The protection of the environment is considered as an important key issue in the
public. And it is not only the maritime infrastructure: Each sea-port is only one element of the entire network
consisting of inland waterways, highways, railroads etc. This leads to another important topic:
transportation in general should be as efficient as possible to reduce the pollution by carbon (CO2) e.g. by
avoiding waiting times.
The enhancement of efficiency of maritime infrastructure and the improvement of productivity of global
transport, and the maritime sector in particular, is a major challenge. Global implementation of
sophisticated and reliable information and communication technology is a key-factor to meet present and
future requirements.
Recent years have shown the potential of information and communication technology by contributing with
about 40% to the increase of the overall productivity within the European Union.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 35 It is more than obvious, that in the near future the pressure on further improvement of productivity in
general, and in particular for the logistic branch, will increase significantly. Maritime transportation is one
key element within the entire logistic chain. But it is not a stand-alone element! Maritime transportation with
all its shore- and ship-based components has to be seen as an integral part of the entire logistic chain.
The e-Navigation concept starts to give answers to major challenges within the maritime world. Further
concepts like VTM or the IALA-NET focus on international or world-wide information exchange. These
concepts are a major step forward, but are more or less limited to the maritime community or even parts of
it.
Similar approaches can be seen for land-based and airborne traffic. Intelligent routing systems and traffic
information systems have proven their reliability and substantial contribution to increase safety and
efficiency as well as productivity.
An example is the aviation system "Required Navigation Performance", RNP. With RNP, airplanes can
land at congested airports at about the same rate in bad weather as in good weather, reducing delays from
low clouds, rain or fog. RNP can also reduce fuel burn, neighborhood noise and flight time by shortening
approaches to airports and letting planes descend continuously with engines at idle, rather than powering
on and off as planes level out and then descend more. By precisely spacing aircraft, RNP can also allow
more takeoffs and landings per hour without building new runways.
Presently, each mode of traffic discusses and develops more or less stand-alone information and
communication systems, partly even not covering all components.
During recent years the national security domain, from duty declaration, immigration control to terrorism
counter measures, played an increasing role. Mandatory reporting systems, procedures or equipment were
introduced, mostly without any economical benefit e.g. for the ship-owners. “Compliance at minimum cost”:
a well known phrase in this context
The next consequent step will be to develop intelligent solutions aiming at increasing the effectiveness of
the existing infrastructure as well as the productivity of the logistic business process itself by covering the
entire logistics process, including on board navigation, waterways and harbour management, terminal
management and further distribution of cargo by different modes of transportation to the end-user. This
calls for a convergence of existing stand-alone systems or those under development into one system.
A prerequisite to design and develop such a system is the willingness of all stakeholders to comprehensive
exchange all relevant information throughout the entire logistics process chain, not only from berth to berth
but including e.g. the shore-based terminal and other supporting processes as well. From experiences
gained support by shipping can in principle be assumed. Port of Singapore “one stop shop” or Newcastle’s
ship arrival system just coming under trial are relevant examples.
A further prerequisite is a coherent process “landscape” to allow for easy and consistent allocation of all
issues of relevance. Because there are probably no experts in detail knowing all systems of consideration,
this process map also must provide the platform for common understanding amongst all involved parties.
ACQUISITION OF RELEVANT SYSTEMS
Productivity is expressed by the ratio of output per input, i.e. labour, equipment and capital. Increase of
productivity is usually achieved by reducing labour cost hence resulting in an increased workload of
operators only partially compensated by technical systems. Automation may replace manpower to a rather
large extend, however, there will always be situations beyond routine which suddenly generate large
amount of data to be captured and processed to relevant information by operators to base decision making
upon.
Other than for data storage to provide the potential for data mining at any time, collecting information and
providing it to operators for real-time decision-making must not aim at maximizing but to optimize the
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 36 content of the human-machine-environment interface. Intelligent information in this sense means to provide
only just what is required under operational conditions to not cause a mental information overflow.
This, however, is an extremely challenging task requiring a detailed knowledge of
•
•
•
•
operational objectives
relevant processes
related tasks
involved process stakeholders
to only name the core drivers. When drafting the information architecture (sources, sinks, message content,
time, validity period etc.) this has to be kept in mind to resist the temptation of data production without any
limits.
There is some experience available to capture and manage production systems within industrial
environments; however, application lags far behind theory and most projects have been conducted within a
rather restricted environment as part of a single entity.
Therefore it might appear a bit frivolous to not only aim at vessel navigation but extend the approach at the
same time to cover logistics and other areas which can benefit from vessel traffic information.
It is obvious that any approach cannot be comprehensive from the very beginning but must provide a
solution to become operative at already an early stage but allow continuous growing never expected to
reach a final static stage. The invention of an “Universal Maritime Data Model (UMDM)” (IALA eNav7/output/14 25/09/2009) appears to provide a feasible approach assumed that
•
•
•
•
it allows interoperability to other dedicated data models for e.g. logistics
it follows a strict entity-relationship-model allowing to capture relevant objects (entities) jointly with
their attributes and relationships organised by classes (entity families) and instances (specific
individual entities)
it is kept in a redundant-free register (“Universal Maritime Data Object Register UMOR”) not
carrying any other information for e.g. visualization than those required to describe entity classes
and instances
all application-oriented processes to use the UMOR-content are being provided externally.
To not get lost within the large number of processes, even when organizing these within meta-process
levels, a domain map is required to represent coherent application areas such as e.g.
•
•
•
•
•
navigation (related to vessels and support services)
approaches (related to sea areas or fairways)
ports
terminals
administrations.
IDENTIFICATION OF RELEVANT PROCESSES AND STAKEHOLDERS
A major obstacle to specify standards to capture marine operations is the variety in combinations of task,
roles and responsibilities. The differences in port models e.g. ranging from fully governmental owned and
operated ports to fully privately owned and operated ports results in quite distinct task and role allocations
and hence sources and sinks of information and responsibilities. Same services in one region might be
provided by a governmental agency on a strict non-profit bases and in another region by a private party
being revenue-oriented. The only way to overcome such heterogeneity is in following a strict processoriented approach. Because operational objectives in most cases are similar in global shipping context,
related processes, at least on a generic level, are comparable. This means the process of berthing a vessel
in a port is usually the same but not the roles of involved parties from harbour master to terminal manager.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 37 On a more detailed level also processes may differ because depending on available resources such as
manpower and equipment as well as on operational conditions to result in a variety of “taxons” all from the
same prime parents.
Objectives
Tasks
Services
Process
Service
Providers
(Actors)
Functions
Service Users
(Actors)
Simplified Architectural View on a System to Identify Processes Sources of reliable process information are both, operators, dealing with the tactical aspects, and
managers, responsible for strategic issues. Capturing of process information requires an unambiguous and
easy-to-understand language. The first and most important question always needs to address the process
objective(s) to measure the system according to required results and not according to the tasks performed,
which might be quite misleading.
Practitioners are usually more familiar with workflows than with processes. The only difference between a
workflow and process being the defined begin and end allows to speak the “workflow language” rather than
confronting operators with an academic jargon.
The “added values” of a process should match the process objectives but experience shows that heritage
systems sometimes lost their added value content only following traditions and hence became redundant.
The level of process detail should be kept as generic as possible avoiding to much fragmentation and
hence loss of transparency and comparability. All aspects of importance can become associated to the
process such as
•
•
•
•
•
responsibilities
roles/qualifications
information
documents
equipment.
Further managerial processes such as
•
•
bench-marking by key performance indicators (KPIs)
activity-based costing (ABC)
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 38 •
•
quality assurance
risk assessment and management
can be linked.
Process ownership and objectives will become crucial in cases where e.g. an administration adds to the
added values of a process to achieve revenues to cover operational costs whereas in another case the
same process is restricted to mere fulfilment of public obligations for safety and security. Most probably it
will not be possible to always distinct between fulfilment of administrations’ obligations and commercial
exploitation when capturing processes and similar processes might become assessed by quite distinct
performance indicators.
There is an important difference between
process capturing in the industry and what is
required for a comprehensive maritime system.
In the industry the activity’s objective is known,
this can be e.g. the invention of an enterprise
resource planning (ERP) tool such as SAP for a
clearly specified application. For the maritime
approach a world of systems need to be
captured without knowing beforehand which
scope of applications the result needs to serve.
To really meet all potential applications the
capturing would need to be so detailed that it
would take a countless number of person-years
to do the job without any chance to ever see the
end of the tunnel. So the approach must provide
a house with rather flexible walls to be gradually
furnished according to actual needs.
Level of Detail
Status
Process End
Status
Process Begin
Added Value
Process The capturing approach must
•
•
•
•
provide a rational classification scheme
be compatible with different architectures (e.g. ARKTRANS)
not depend on a dedicated capturing tool
allow a fragmentary record open for later amendments.
It is, however, not necessary to re-invent the wheel. A comparison of available process classification
schemes resulted in the standards for enterprise architecture modelling ISO CEN 19439 + 19440 being
sufficiently appropriate. These standards are derived from CIMOSA (computer-integrated manufacturing
open system architecture developed by the AMICE consortium in the 1990s).
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 39 Architectural Views
Resources
Organisation
Functions
Information
Level of Process
Detail
(„Process Zoom“)
Reference
Architecture
Generic
Level
e.g. Navigational Assistance
Partial
Level
e.g. Pilotage
Particular
Level
e.g. Boarding
e.g. Conning
e.g. Deboarding
CIMOSA Process Capturing Scheme (partially modified by J. Froese) The CIMOSA process capturing scheme allows to mirror existing systems. In case of system design or reengineering structured modelling is required to define processes optimised to achieve specified goals.
CIMOSA also provides a usable approach.
System Design/Re-Engineering
Requirements
Model
Specification
Model
Validation
Model
Implementation
Model
Operation
Model
Approach to Design or Re‐engineering a System (according to CIMOSA partially modified by Froese/Zuesongdham) 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 40 OPTIMISATION OF THE LOGISTIC-CHAIN BY A COMPREHENSIVE DATA ACCESS AND VALUEADDED SERVICES
There are many possible applications of vessel traffic-related data to provide improved services for e.g.
•
•
•
•
•
•
•
•
optimised scheduling
voyage economy
reduction of CO2 footprints
meteorological routing
fishery
off-shore exploration, drilling and production
prevention from illegal intruders
combating illegal actions such as drug trafficking and pirates
all within the navigational domain.
Recognizing the dependency of logistics services such as
•
•
•
•
•
intermodal pre- and post-sea transport and storage
scheduling of cargo-related services such as e.g. customs, security, veterinary services (for e.g.
frozen meat)
traffic flows
transhipment resources use
warehousing, production and trade
on vessels’ voyages and hence cargo or space availability, the huge potential of added values becomes
obvious.
Container Traffic in the Port of Hamburg (Source: Welt.de) An increasing problem for those ports situated in the heart of a city present complains of residents living
close to the port. Early morning traffic from a RoRo-port like e.g. Dublin resulting in noise annoyance or
heavy container traffic in the Port of Hamburg at peak times resulting in traffic jams around the port need to
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 41 become better scheduled in order to avoid peaks and inconvenient periods of the day. Thus land traffic
processes need to become better matched to sea traffic in the future requiring long-term planning and
voyage guidance of ships.
System life cycles as well as operation life cycles are always becoming shorter. Any solution to foster
integration and inter-operability may not be based on a current system snapshot but must take continuous
change into consideration. Today technology provides the methodologies and the tools to meet these
challenges by establishing a virtual seamless data pool to allow all involved actors to generate the
information they need for planning, executing and monitoring their processes. In shipping and logistics,
however, seamless information landscapes are still far away from being realized. At any fraction of the
supply chain requiring transhipment cargo data must become repeatedly re-entered into various document
capturing systems not only causing additional workload and hence cost but also document errors and
delays.
Whereas in the past transhipment times, in most cases requiring temporarily storage of goods, were
sufficiently long to provide a kind of a time buffer to make up for all shortcomings, nowadays the time
between production of goods and invoicing in international trade must be kept as short as possible.
Transhipment delays and document errors can quickly destroy the small margins. The willingness of
involved parties to feed the data pool therefore can be assumed as long as protection of sensitive business
data can be guaranteed.
THE ROLE OF THE NATIONAL AIDS-TO-NAVIGATION AUTHORITIES
National Aids-to-Navigation Authorities are major stakeholders in the entire (maritime) logistic process.
Mostly being responsible for the safety and efficiency of maritime traffic they are authorised to collect and
process all relevant data from shipping. Mandatory ship-reporting systems, VTS based on radar, AIS and
VHF communication are established and operated, in general following relevant recommendations and
guideline issued by IALA.
In addition, environmental data, hydrological and meteorological data, status data on Aids-to-Navigation,
the waterways and other infrastructure objects are collected by those authorities.
However, some of the information required will potentially be of commercial sensitivity or needs to be
treated confidentially due to security reasons or other national regulations.
This was the reason for failures of some technically sound maritime information platforms in the past.
Private logistics providers just did not want to expose all data required to optimize both, transport and traffic
systems.
To overcome this challenge national Aids-to-Navigation Authorities (national members of IALA) could act
as a “Trusted Third Party Information Provider”.
National Authorities are mostly governmental bodies or acting on behalf of those. They are strictly
committed to commercial neutrality, grant that all safety and security related aspects will be considered.
This would result in confidence of shipping and the maritime industry, that data security is ensured and
information will only be used within agreed schemes.
In addition, this scenario would result in a win-win situation for the logistics industry as well as for the
national Authorities.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 42 Traffic situation on the Kiel‐Canal (Source: wsv.de) A simplified example is the ship-data handling system for the Kiel Canal, operated by the Federal
Waterways and Shipping Administration, Germany. More than twenty different “users” are connected to
that System:
-
The Administration, being responsible for the operation and maintenance of the Canal and a safe
and efficient traffic organisation
Pilots and helmsmen to support the safety of navigation on board
Federal Agencies like Customs and immigration Control
Shipping Industry, represented by handling Agents
This system has proven to be very beneficial for all participants, although it reflects only parts of the entire
process.
Accepting the role as a „Trusted Third Party
Marine Information Provider” the national Ato-N Authority would be in charge to identify
all interfaces, design and operate the
information- and communication-system.
A prerequisite is the knowledge of the entire
logistic process and a close consultation
with all stakeholders.
A prerequisite is the knowledge of the entire
logistic process and a close consultation
with all stakeholders.
Global trade results in a global business
process. Global exchange of information
between National A-to-N Authorities, mostly
National Members of IALA, calls for IALA to
play a key role in this respect.
Screenshot ship‐data handling system Kiel‐Canal (Source: wsv.de) 17th IALA Conference IALA-Net could be seen as a first step
towards a true global system, based on
national communication- and information
system.
17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 43 IALA would be the perfect body to give guidance to the national Authorities on how to:
-
identify and evaluate the relevant logistic processes
design and implement a national information- and communication-system to support the entire
maritime logistic process,
harmonise the national systems and to be linked together as a global system
CONCLUSIONS AND RECOMMENDATIONS
Sophisticated world-wide harmonised information and communication systems show a great potential to
enhance efficiency and productivity of the global transport, and the maritime sector in particular.
To achieve a common understanding it is required to identify and focus first on those logistic processes,
which are identical or almost identical worldwide, regardless of the organisational structure of those
involved in the process. This should be done by developing a domain map representing coherent
application areas.
The Universal Maritime Data Model (UMDM), currently under development by IALA, would be a feasible
approach. Further work should take into consideration that the model follows a strict entity-relationshipmodel and is kept in a redundant-free register (Universal Maritime Data Object Register (UMOR).
National-Aids-to-Navigation Authorities, acting as a “Trusted Third Party Marine Information Provider”,
would result in confidence of shipping and the maritime industry to expose all data required. A win-win
situation for all parties involved would be achieved.
Considering the potential benefits of a world-wide harmonized information- and communication-system it is
recommended that:
-
-
IALA should prepare a guideline on how to carry out a process analysis, to make sure that identical
or almost identical processes world-wide are identified and evaluated based on a common method
and standards.
IALA should develop a web-based tool providing generic processes as a basis for the individual
analysis to be carried out under the lead of National A-to-N Authorities.
IALA may consider to act as a registrar for a domain map,to represent coherent application areas
on a world-wide basis.
IALA set up a recommendation to encourage National Members to act as “Trusted Third Party
Marine Information Providers” and give guidance on how to develop and implement “Value-added”
services to the maritime logistic industry.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 44 Intelligent Information Systems for e‐Navigation N. Ward, General Lighthouse Authorities of the United Kingdom and Ireland BIOGRAPHY
Dr. Nick Ward is Research Director for the General Lighthouse Authorities of the UK & Ireland, with
responsibilities for radio-navigation and communications projects, including e-Navigation, as well as research
& development strategy. He has been closely involved with the international standardization of Differential
GNSS and AIS, is vice-chair of the IALA e-Navigation Committee, a Chartered Engineer and a Fellow of the
Royal Institute of Navigation.
ABSTRACT
Providing the mariner with the right information at the right time will be a key element of e-Navigation.
Overloading the user with unnecessary information is almost as bad as providing wrong information – it
makes it difficult, if not impossible, to extract the right information. In many situations the navigator does not
have time to go and look up the information they need in a book and downloading it from a database or a
website could be a dangerous distraction. Can systems be designed so that they “know” what information
is needed in a particular situation and location, and can go and find it, presenting it in an easily identifiable
and understandable format? That may seem a futuristic, even unachievable objective, but e-Navigation is
still a “future concept”, with an implementation plan only due to start in 2012 and likely to last a decade.
Therefore such forward-looking aims are quite appropriate as subjects for research.
This paper will set out ways in which intelligent information systems might be achieved and the benefits
they could offer. In particular the use of software agents to locate and retrieve relevant information, linked
to location will be reported. Methods of displaying the information in a comprehensible manner and
exchanging data in standardised formats will be also be proposed. Finally ways of ensuring the integrity
and authenticity of data will be considered and conclusions will be drawn as to how and when such
developments might be achieved.
RESUME
Fournir au marin la bonne information au bon moment sera un élément clé de l’e-Navigation. Saturer
l’usager d’informations inutiles est aussi mauvais que lui fournir une information erronée – il lui devient
difficile, voire impossible, d’extraire la bonne. Très souvent le marin n’a pas le temps de se déplacer pour
aller chercher l’information dans un livre, et la télécharger à partir d’une base de donnée ou d’Internet peut
générer une distraction dangereuse. Peut-on concevoir des systèmes qui « savent » quelle information est
nécessaire dans une situation et un endroit spécifiques, qui peuvent aller la chercher et la présenter dans
un format facilement identifiable et compréhensible ? Cela peut sembler un objectif futuriste, même
irréalisable, mais l’e-Navigation est encore un concept d’avenir, dont la mise en œuvre ne doit commencer
qu’en 2012 et devrait durer une dizaine d’années. Ce sont donc des objectifs qui constituent des objets de
recherche valables.
Ce rapport va présenter les moyens de réaliser des systèmes intelligents et les avantages qu’il peuvent
offrir, notamment l’utilisation d’agents logiciels pour localiser et rapatrier l’information appropriée, en
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 45 adéquation avec la position. On proposera aussi des méthodes de visualisation de l’information de façon
compréhensible et d’échange de données dans des formats normalisés. Enfin, on explorera les moyens
d’assurer l’intégrité et l’authenticité des données et on présentera des conclusions sur « comment et
quand » ces développements pourront être réalisés.
1. INTRODUCTION
At the XVIth IALA Conference in 2006 a paper was presented on Aids to Navigation (AtoN) as Information
Systems, proposing a standard format for exchanging AtoN data and a generic display enabling a wide
range of information and messages to be relayed to the operator (1). There were also several papers
discussing the application of Geographic Information Systems (GIS) for AtoN planning and information
management. In late 2007 IALA held a GIS and Simulation Workshop, and this led to a draft guideline on
AtoN Information Exchange and Presentation (2). Over the same period a working group of the eNavigation Committee has been developing a Universal Maritime Data Model (3).
This paper describes how these developments relate to e-Navigation and suggests ways in which the
handling of information might progress during its implementation.
2. RELEVANCE TO E-NAVIGATION
IALA’s work on AtoN Information, simulation, GIS and the Universal Data Model aligns well with several of
the identified future directions of e-Navigation, and will form a good foundation for the continuation of
IALA’s work in support of e-Navigation.
The first of the high-level generic user needs for e-Navigation identified at IMO NAV 54 was a Common
Maritime Information/Data Structure (4): “Mariners require information pertaining to the planning and
execution of voyages, the assessment of navigation risk and compliance with regulation. This information
should be accessible from a single integrated system. Shore users require information pertaining to their
maritime domain, including static and dynamic information on vessels and their voyages. This information
should be provided in an internationally agreed common data structure. Such a data structure is essential
for the sharing of information amongst shore authorities on a regional and international basis.”
Information about AtoN will be required as an integral component of the “information” being referred to
above.
3. ATON ATTRIBUTE INFORMATION
The exchange of AtoN information between any parties in a digital environment will require internationally
agreed standards so that information can be automatically compiled for sending and automatically
understood by systems that receive it.
Such a harmonised approach will facilitate the management of information about AtoN, and in particular
information that is relevant to mariners: “situation normal” data (position, colour, shapes, light etc) and also
situation abnormal (lost top mark, light on reduced range, unlit etc). In GIS terms this sort of information
can be described as attribute data (information particular to a GIS object such as an AtoN) and metadata
(data about the attribute data).
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 46 Digital representation of Visual AtoNs is a sub-category of Traffic Objects in the present draft of the IALA
Universal Maritime Data Model. Radio-navigation AtoNs, such as GNSS are considered as a sub-category
of Physical External Entities other than traffic objects.
4. HARMONISED APPROACH
Having accepted the need for a harmonised approach, the first step was to investigate relevant, existing
systems and standards.
It was apparent that several relevant standards already existed, therefore an IALA Guideline was prepared
to bring these to the attention of IALA Members and advise how they could be implemented.
Noting the need for AtoN authorities to communicate information about AtoN to Hydrographic authorities, it
was recognised that the most appropriate data transfer standard could be those already developed for use
with ENC data, the present IHO S-57 (5) and the future standard S-100 (6).
5. GUIDELINES
IALA has developed the following guidelines for AtoN attributes and metadata when implementing
applications for AtoN Information collection, exchange and presentation:
5.1
Data representation for exchange of information should conform with IHO Special Publication S-57
in the short term (2010-2015).
5.2
The symbology should be in accordance with IMO SN Circ. 243 (7).
5.3
In the medium to long term (2015-) data formats should align with S-100 and IALA should establish
a data registry for AtoN information through the IHB.
5.4
Applications should follow the OpenGIS® Architecture for storing and accessing feature data in
relational or object-relational databases (ISO 19119:2005) (8).
5.5
Datasets should be described using the spatial and temporal schemas defined in ISO 19115:2003,
Geographic Information – Metadata (9).
5.6
A mark-up language defined by SGML should be employed for the exchange of data between
administrations, suppliers and users. Attributes should be used to define data-types in the schemas (ISO
8879:1986) (10).
6. EXAMPLES OF INFORMATION MANAGEMENT SCHEMES
There are several information management systems relating to AtoNs, already in existence or under
development.
The Australian Hydrographic Office (AHO) in cooperation with the Australian Maritime Safety Authority
(AMSA) has produced an Excel application for compiling AtoN information in a format suitable for input to a
GIS and also the AHO’s AtoN database (11).
The UK Hydrographic Office has customised software (POLAR) for the same purpose. For the exchange
of such data a likely message format is XML (Extensible Markup Language) (12).
The General Lighthouse Authorities have demonstrated XML schema for AtoNs (lighthouses, buoys and
DGPS stations) and IALA is in the process of implementing the DGNSS application on its website (13).
The Portuguese Instituto Hidrografico has in place a web-based system supported by robust navigational
databases, providing mariners with Maritime Safety Information, including tidal and wave data, Notices to
Mariners, NAVTEX and Chart Updates (14).
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 47 Finally a researcher at the University of Arizona, with support from the USCG R & D Center, has developed
a Maritime Information Management Language (MIML) based on XML and relating to S-57. Subject to
general acceptability and copyright considerations, this could be a candidate for an international standard
mark-up language for this application (15).
7. BENEFITS
Once such standards are in use, with suitable security measures, administrations will be able to coordinate
management of AtoN information in a digital environment and this will in turn facilitate sharing of
information with:
•
mariners in real-time or near real-time;
•
shore-based operators;
•
hydrographic authorities (for inclusion in official navigational products);
•
Original Equipment Manufacturers (OEMs) for inclusion in non-official chart systems such as
Electronic Chart Systems (ECS), chart radars and “AIS radars” and other equipment databases.
8. INTELLIGENT INFORMATION SYSTEMS
The approach proposed to standardisation will facilitate establishment of a Common Maritime
Information/Data Structure, the first of the high-level generic user needs for e-Navigation. The examples
mentioned above illustrate how this can be achieved, dealing with data in a conventional manner. However,
as more and more of the information needed for navigation and related tasks is available on-line and
continuous internet access becomes the norm, it will be possible to obtain the relevant information more
rapidly and reliably using intelligent search techniques. By providing their information in appropriate ways
maritime administrations can facilitate this improvement in efficiency and effectiveness.
Semantic web solutions, incorporating description of content in the database allows a computer to perform
automated information collection and processing. The use of classes and attributes, as in object-oriented
programming, allows the identification of relevant information by the computer. The Unified Modelling
Language is used in this approach and has been employed in the development by IALA of both an initial
technical architecture for e-Navigation (16) and a Universal Maritime Data Model
Neural networks can “learn” or be “trained” to adopt search patterns that will arrive at the required answers
more quickly and dedicated software agents can be used to acquire information with particular relevance,
e.g. to location or class of vessel.
However, the need to ensure integrity of information and system security is even more important for data
sources accessed by machine than for those used by a human operator.
9. ACKNOWLEDGEMENTS
The contributions of AMSA personnel to the draft guidelines are acknowledged, in particular Nick Lemon
and Mahesh Alimchandani. The valuable advice of Robert Ward, Director of IHO, on the application of IHO
S-57 and S-100 is also gratefully acknowledged.
10. REFERENCES
10.1 IALA 2006. Ward N. Aids to Navigation as Information Systems.
10.2 IALA 2009. Draft IALA Guideline on AtoN Information Exchange and Presentation.
10.3 IALA 2009. Draft Future Recommendation e-Nav 0220, Universal Maritime Data Model.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 48 10.4 IMO 2008. Report of NAV 54, Annex 12.
10.5 IHO Special publication No.57 (S-57).
10.6 IHO Special publication No.100 (S-100).
10.7 IMO SN/Circ. 243 Guidelines for the presentation of navigation-related symbols, terms and
abbreviations.
10.8 ISO 19119:2005, OpenGIS® Service Architecture
10.9 ISO 19115:2003, Geographic Information – Metadata
10.10 ISO 8879:1986, Standard Generalized Mark-up Language.
10.11 AHO/AMSA 2009. Aid to Navigation Input Template.
10.12 UK Hydrographic Office 2009. POLAR software.
10.13 GLA 2006. XML Schema for Buoys.
10.14 Instituto Hidrografico, Portugal 2009. ANAVnet.
10.15 R Malyankar, Arizona State University 2002. Vocabulary Development for Mark-up Languages --- A
Case Study with Maritime Information.
10.16 IALA Draft Recommendation e-NAV 101 Technical Architecture for e-Navigation.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 49 Application of Three‐Dimensional Simulation System to the Placement and Management of Aids to Navigation Guowei CHEN, Shanghai Maritime Safety Administration Aids to Navigation Department, P.R. of China ABSTRACT
With the construction of Shanghai international shipping center, the waterway construction, aids to
navigation construction and service level and also the management standard of Shanghai port are required
to be increasingly improved. Yangtze River estuary and adjacent waters are the strategic passage to
guarantee the navigation safety of Shanghai port and even the whole area along the Yangtze River. These
waters have a large navigable area with big ship flux, and the natural conditions, navigation conditions and
the hydro meteorological conditions of which are all very complicated. All of these have put forward higher
requirements for the construction, maintenance and management level of the aids to navigation. In order to
better the maintenance and management level and evaluate the aids to navigation efficacy scientifically,
how to improve the rationality and practicality of the placement of the aids to navigation becomes to be a
hot topic in our maritime field, with the purpose of meeting the demand of safety and high efficiency
navigation of Shanghai port. So, it is very significant to study a comprehensive and scientific evaluation
method on aids to navigation efficacy.
This paper illustrates a three-dimensional simulation system and its application in the management and
evaluation of aids to navigation, and puts forward a new method on the evaluation of aids to navigation
efficacy that is combination of three-dimensional simulation and relative evaluation methods, and also has
future prospects of the system application in the end.
Keywords: Aids to navigation; Three-dimensional simulation; Aids to navigation management; Evaluation
RÉSUMÉ
Avec la construction du centre maritime international de Shanghai la voie navigable, les aides à la
navigation, le niveau de service et de gestion du port de Shanghai doivent être considérablement
améliorés. L’estuaire du Yangtze et les eaux adjacentes sont un passage stratégique garantissant la
sécurité de la navigation dans le port de Shanghai et dans toute la région du fleuve Yangtze. Ces eaux
comportent une large zone navigable à fort trafic, mais ses conditions naturelles, conditions de navigation
et hydro météorologiques sont fort complexes. Ceci a entraîné des exigences plus élevées pour la
construction, l’entretien et la gestion des aides à la navigation. Pour améliorer la maintenance et la gestion,
évaluer de façon scientifique l’efficacité des aides à la navigation, l’amélioration de la rationalisation et
l’aspect pratique du positionnement des aides sont devenus sujets d’actualité dans notre domaine maritime,
avec pour objet de répondre aux demandes de sécurité et de grande efficacité de la navigation dans le port
de Shanghai. Il était donc très important de mettre au point une méthode d’évaluation scientifique et
détaillée de l’efficacité des aides à la navigation.
Ce rapport va montrer une méthode de simulation en 3 dimensions pour la gestion et l’évaluation des aides
à la navigation, et mettre en avant une nouvelle méthode d’évaluation de l’efficacité des aides qui est une
combinaison des méthodes de simulation tridimensionnelle et d’évaluation relative. Il présentera enfin les
potentiels de l’application de ce système.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 50 1 BACKGROUND
Yangtze River estuary and adjacent waters are the strategic passage for safety navigation of Shanghai port
and even the whole area along the river. Aids to navigation are the main components of the navigation
system, which play a vital role on the safety of ships in Shanghai port and adjacent waters. So, if the
placement of the aids to navigation in these areas is scientific, rational and practical has a close relation to
the ships’ safety in the whole waterway.
Shanghai Aids to navigation department is the administration department of the placement and
management-maintenance of the aids to navigation in Yangtze River estuary and adjacent waters. It
undertakes the construction, management and maintenance of the aids to navigation in Shanghai water
area (including Huangpu River, Yangtze River estuary, Yang Shan deep water port and northern water area
of Hangzhou bay), and also the tasks of maintaining some part of the aids to navigation in the other areas
of East Sea. Shanghai water area covers a large scale, and its natural conditions, hydro meteorological
conditions and traffic conditions are all very complicated. And, it has big ship flux and many intersections.
Besides, there are many different kinds of aids to navigation in this area, the total number of which has
came up to 803 until the end of the November 2008. And, a great number of them are visual aids to
navigation and radar aids to navigation, such as buoys, light vessels and beacons which have the functions
of radar reflectors, AIS reflectors and AIS virtual aids to navigation. These aids to navigation play a vital role
on the safety navigation, route assignment and label and also the construction of “Water Highway ”. On the
other hand, the navigation requirements and placements requirements of plenty of aids to navigation put
forward higher requirements on the placements, maintenance and management of the aids to navigation.
Fig 1 shows the placement condition of aids to navigation in Shanghai water area.
In order to further develop the functions of Yangtze River golden waterways and accelerate the
construction of the Shanghai international shipping center to provide better services and promote
development of shipping and the economy in Yangtze River Delta Area, using the concept “Ensuring safety,
Convenient navigation, Improving humanized service level” to guide the placement and construction of aids
to navigation is an important part in a period in current and future [1].
Faced with the complicated navigation condition, how to increasingly improve the construction level of aids
to navigation to make the placement much more scientific, rational and practical is one of our chief tasks,
not only to meet the demands of safe and efficient navigation, but also to improve the maintenance and
management level[2][3].
Three-dimensional simulation system of aids to navigation is developed under the condition that using
scientific methods to assist the plan and construction of aids to navigation, and ,using advanced
technologies to improve the maintenance and management level of aids to navigation, and using
comprehensive and accurate evaluation method to evaluate the aids to navigation efficacy. The threedimensional simulation system provides an intuitive and effective method for improving the placement
rationality of the aids to navigation and evaluating the efficacy comprehensively and accurately. It also
provides a reliable decision-making assistant method for the placement, which can further develop the
functions of the aids to navigation and improve their service level.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 51 2 THREE-DIMENSIONAL SIMULATION SYSTEM OF AIDS TO NAVIGATION
This system was made earlier stage demonstration from 2005, and was put into trial operation after
complete research and development in the end of 2007. After more than one year’s trial operation, this
system now is put into practical operation, and also achieves positive effect, which lives up to the respected
design requirements.
Using this system we can master the conditions of the aids to navigation in the whole water area with the
help of three-dimensional dynamic visual simulation technology, network communication, AIS data
communication and information filtering technology and so on. And, the system makes use of free
navigation and virtual navigation technology to know the performance of each aid. Besides, it can correctly
evaluate the aids to navigation efficacy by changing the height of the driver’s viewpoint in the ship simulator,
the distance to the chose aid to navigation and the visibility under that navigation environment and other
methods combined with the predetermined evaluation model. This simulation system also can simulate the
planning aids to navigation in advance to observe the effect of the placement. It also can be used to
dynamic management of the aids to navigation and ships’ track, and, analysis of the ship accidents through
tracking and managing the data of AIS on aids to navigation and ships. Fig 1 illustrates the structure of the
three-dimensional system. Fig 3 shows our real system.
Display terminal
Navigation
information
and visual
display
Hardware devices
and interfaces
HUB
Data processing
computer
System
control and
ECDIS
AIS Data
2.1 System composition and function of each part
2.1.1 System composition
This simulation system is composed of a 40°visual display system, a system control machine with ECDIS, a
navigation information and visual image display, a video distributor and a HUB. And the 40°visual display
system consists of a three-dimensional simulation system operation platform and a large screen display
system. The data or the image from navigation information and visual image display is sent to the projector
or displayed using video matrix. And the horizontal visual angle of the visual image is 40°.
2.1.2 Function of each part
1) Single channel visual display system
The system can display the real scenery or navigation display the real scenery. It can display the external
scene around the ships’ navigation water area including the aids to navigation. Besides, the system has
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 52 texture, illustration and wave effect, and so on. The visual display system has a 40°horizontal angle and the
elevation angle is 30°.
2) Simulation operation platform
It can simulate the navigation of the ships for aids to navigation, or realize the simulation navigation after
choosing the type of the ship.
3) ECDIS and operation platform of the principal controller
It is used to control the visual display or the roaming. And, it can display the two-dimensional chart, record
the data, edit the route and navigation aids and evaluate the aids to navigation efficacy using
predetermined evaluation model. The principle controller and the ECDIS are the central control units of the
integrated handling simulator to set the operation plan control the operation and coordinate the information
exchanges between the computers. Besides, setting the position of the ships, the environment conditions,
aids to navigation conditions and the planning schemes of the navigation aids, the maintenance,
management and retrieval of the database, display and playback the AIS data and evaluation of aids to
navigation efficacy are all realized in these two units.
4) The data processing computer
The data processing computer receives and processes the AIS data and other related information, and the
results will be used in the system.
5) Navigation information and visual image display
This unit is to process the control instructions, display the environment scenes of the set areas and
calculate the dynamic responses of the simulation ships to the manipulations.
2.2 System performances
1) Real-time display
The system can display the surrounding conditions in real time including the aids to navigation and nearby
ships’ information under the pre-set wind, flow and the wave. This performance can be realized by the realtime manipulations on the simulation rudder and screw under the conditions of pre-set simulation ships,
environments and so on.
2) Evaluation the efficacies of nearby aids to navigation
This system can evaluate the efficacy of the nearby aids to navigation using predetermined evaluation
model, which can provide references for the future placements and adjustments of the aids to navigation.
3) The simulation system can display the real-time information of at most 100 objects around and their
three-dimensional images. It also tracks the aids to navigation equipped with AIS and the target ships.
4) The system can record the tracks of the simulation ship and the target ships.
2.3 Research targets
This system makes use of mathematical modeling, virtual scene, image processing, multimedia, network
communications, dynamic simulation, integrated database and many other high-techs, aiming to advanced
design concept, advanced technologies, practicality and reliability of the system, realistic effect of the
simulation, correctness of the evaluation results of the aids to navigation efficacy. And also, we pay
attention to the pertinence and practicality of the system. Besides, the system is designed to be convenient
for upgrading and extension considering the future development.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 53 1）In this system, a person is set in any place in the areas of jurisdiction, from any angle, in a variety
navigation pattern (such as fixed direction fixed speed, design routes, free navigation, etc. ) to observe the
nearby aids to navigation and surrounding scenes, so the observer feels as self participation with a strong
scene feeling.
2）In this system, we can place the planned aids on the three-dimensional simulation chart, according to
the program of aids to navigation placements combination of the route identification function of the ship’s
AIS track. And then, we can take simulation navigation experiments to check the reasonability of the
placements of the aids to provide a comprehensive preview, experience and observation of the actual
placements of aids. Besides, we can compare the different kinds of programs of the placement, which can
be used as a useful way to check and judge the feasibility and superiority of the plans.
3）We can understand the collision process between the ship and the aids to navigation much more
intuitively by simulation playback of the accidents, combination of the aids to navigation telemetering and
telecontrol and the AIS data of the ship. It can be used to analyze the reasons of the collision and the
extent of the damage, which can not only provide references for decision-making, but also can be used to
maritime analysis.
2.4 Main functions
1）This system can display the visual images of environments and the aids to navigation in the areas lively,
and simulate the combined effect of the aids to navigation and surrounding environments under the sea
condition of simulated day and night, poor visibility or different levels of wind and wave and other complex
conditions. It also provides different observation effects in any place, from any angle and a variety of
navigation pattern (such as fixed direction fixed speed, design routes, free navigation, etc.).
2) It can display the ECDIS in the areas of jurisdiction the aids to navigation and the AIS target ships.
3) We can set the aids to navigation according to the actual conditions or the requirements of planning of
the aids. (Setting virtual fairway and virtual aids to navigation on the two-dimensional chart, and observing
the navigation effects in the three-dimensional visual images). It is illustrated in Fig 5.
In this system, we can manage the aids to navigation model base, and provides a certain edit function on
the models so that the aids models can satisfy the requirements of the actual types, sizes and appearances.
It also provides kinds of methods to set the aids to navigation in the three-dimensional system and also edit
the characteristics of the lights, such as, according to the coordinates of the aids, automatically set
according to the starting point and the spaces between the aids, randomly setting on the three-dimensional
chart using the mouse, and so on.
5）This system can be used to simulate the effects of the placements of aids to navigation in the main
fairway, which provides related data for the efficacy evaluation of the aids to navigation in Shanghai port
and Yangtze River estuary areas.
6）The system has access to the AIS data to simulate and display the traffic conditions of the fairway. And,
it can combine the route identification function of the AIS track to provide references for the placements of
the aids to navigation.
7）We use the spatial data and attribute data of the already developed aids to navigation telemetering and
telecontrol system to build the real time association of the model states of the three-dimensional aids and
the dynamic data from aids to navigation telemetering and telecontrol. It can realize the query and alarm
functions of the characteristics data and the telemetering data. The surrounding scenes and the conditions
of all the aids to navigation will be displayed intuitively, lively and comprehensively by using the threedimensional simulate system of aids to navigation.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 54 8）This system can be used to simulation and playback of the collision accidents, so that we can
understand the process of the accidents when the ship collisions to the aids, and then analyzing the
reasons of the collision and the extent of the damage to provide references for decision-making of the
protections of the aids to navigation.
9）Comprehensive evaluation of aids to navigation efficacy
Aids to navigation efficacy is a comprehensive index, which reflects the reliability, maintainability, usability
and service level and other indexes of the aids. The evaluation of aids to navigation efficacy contains
quantitative and qualitative evaluation.[1] The placement of the aids to navigation can be much more
scientific and reasonable after the efficacy evaluation, especially the quantitative evaluation.
The methods of the evaluation of aids to navigation efficacy can be practical measurement method and
simulation method.
The practical measurement and evaluation of aids to navigation efficacy
This method mainly takes continuously technical measurements on the aids to navigation along the
navigation waterway in the form of alternate working of the technical measurement group. This method is
very slow in measurement, and has a low-efficiency. Besides, it is very easy to be influenced by the rain,
fog, heavy wind and wave and other bad weather conditions.
Simulation-based evaluation of the aids to navigation efficacy
Efficacy of single aid to navigation C1
Visibility C21
Hydro
meteorological
conditions C2
Wind, flow and wave
Breadth of the fairway C31
Fairway
factors C3
Curvature of the fairway C32
Influencing
factors
Navigation obstruction C33
Ship traffic
conditions C4
Maintenance and
management
conditions C5
Accidents
conditions C6
Ship size C41
Ship flux C42
Maintenance and management system
C
Maintainers and managers’ level C52
Infrastructures and equipment level C53
In order to
solve the
existing
problems
and
overcome
the
drawbacks
in the
practical
measureme
nts of the
aids to
navigation
efficacy, we
put forward
to develop
the Threedimensional
Simulation
System of
aids to
navigation.
The Threedimensional
Simulation System of aids to navigation can real time display the set or planned aids and surrounding
scenes under many different conditions, such as, different ship types, different fairway conditions, different
traffic conditions, different wind, flow, wave and visibility conditions and different navigation status, and so
on. We can
Fig 2 The index system of the evaluation model evaluate
the aids to
Users’ feedback C7
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 55 navigation efficacy according to the judgment of the visual and the predetermined evaluation model. The
simulation-based evaluation can cut down the cost of practical measurements, and can improve the
efficiency. Besides, we can provide better assistance for the measurements of the aids to navigation to
make the evaluation results much more accurate and reliable by adjusting the error timely in the simulationbased measurements according to the data from practical measurements.
Simulation-based evaluation includes building evaluation model and simulating the navigation under many
different conditions.
There are many kinds of methods to build the evaluation model, including Experts Consultant method,
Fuzzy Comprehensive Evaluation, Grey Clustering Analysis, AHP, and so on. These methods all have
index set, influencing factors set and weights of each index. These methods can be divided into three kinds,
which are quantitative analysis, qualitative analysis and combination of quantitative and qualitative analysis
[4]
.
Using the Fuzzy Comprehensive Evaluation, Grey Clustering Analysis, Fuzzy Neural Network and other
quantitative evaluation methods can let the research of the aids to navigation efficacy change from fuzzy
and non-systematic study to quantitative study. But these methods are all used to evaluate the rationality,
availability and the efficiency of the aid to navigation when it is already set. And, these methods also
contain some subjective factors[5].
In our system, we will not only evaluate the aids already set, but also the planned aids to navigation. The
index system includes service level of the aids, the safety level providing to the ships and the adaptation
level to future development, and so on[6][7]. The index system of the evaluation model in the simulation
system is illustrated in Fig 10.
3 APPLICATIONS
The threedimensional
simulation system
played an
important role on
the evaluation of
the aids to
navigation efficacy
in Shanghai water
area, tentative
design in the
placements of aids
to navigation and
judgment and
(a) Setting the virtual route (b) Setting new aids to navigation Fig 11 Setting the virtual route and new aids to navigation analysis the ship accidents after putting into operation. This paper introduces some typical cases as
follows:
•
Tentative design in the placements of aids to navigation: Placements of aids to navigation in 100MW
wind power generator demonstration project in Donghai Bridge. The general situation of the project
is to set 8 new buoys in the eastern water area of Donghai Bridge, and to reposition a buoy.
1 Setting the virtual route on the two–dimensional chart, and setting new aids and repositioning the
○
aids to navigation. Show in Fig 11.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 56 2 Displaying the new-setting and repositioning aids, and observing the effects of placements by
○
simulation navigation. Show in Fig 12.
(a )New‐setting route and aids to navigation (b )Observing the effects of placements by simulat ion navigat ion Fig 12 Three‐dimensional display and observing the effects •
Simulation-based evaluation of the aids to navigation efficacy
1 Placements of Anti-collision Pier in the main channel of Donghai Bridge. Show in Fig 13.
○
Fig 13 Placements of Ant i‐collision Pier in the main channel of Donghai Bridge 2 Adjustment of the bridge opening marks of the main channel of Donghai Bridge. Show in Fig 14.
○
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 57 Figure 14 3.
Accidents analysis of ship collisions : The collisions accident of “Zhongchuang 118” and “Fuzhou ” in
Wusong water area
1 Importing the AIS data of collisions of “Zhongchuang 118” and “Fuzhou ”, choosing the speed of
○
the playback. Show in Fig 15.
Fig 15 Importing the AIS data and playback the collision 2 Displaying the track of the two ships in the Three-dimensional system, recurring the accident,
○
providing accident analysis. Show in Fig 16.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 58 Fig 16 Recurring the accident 3 CONCLUSIONS AND PROSPECTS
At present, the studies on using the three-dimensional simulation system of aids to navigation to evaluate
the aids to navigation efficacy are still very rare. So, it is necessary to enhance the study in this aspect. And,
there is still no mature model in analyzing the influences of the wind, flow and wave, and also the
superimposition of the three factors both home and abroad.
In order to evaluate the aids to navigation efficacy effectively to guarantee that the placements of the aids
meet the demands of safety navigation and reasonable placements, it is necessary to build a set of
scientific and reasonable evaluation method and evaluation index system, which provides theory basis for
the evaluation in three-dimensional simulation system. Considering the fact that the simulation technology
is increasingly mature and much more studies have been put into the evaluation methods, it is entirely
possible and extremely promising to evaluate the aids to navigation efficacy based on the threedimensional simulation system of aids to navigation.
With the rapid development of China's economy and shipping, the requirements on the constructions of
the ports and the constructions of the fairways and aids to navigation will be higher and higher. The
construction and application of the three-dimensional simulation system of aids to navigation will provide a
better and scientific assistance to the planning and management of the fairways and the aids to navigation.
The successful building of the three-dimensional simulation platform will lay a good foundation for further
application and study. In the next step, we will integrate the data including the environment information
(hydro meteorology conditions, visibility, etc), related data of aids to navigation (basic data, telemetering
data, etc) and basic data of the ships. And the reality degree will be improved. The evaluation model will be
increasingly improved by accumulating the data from technical measurements and evaluation to make sure
that the three-dimensional simulation technology will actually provide scientific judgments basis for
constructions, maintenances and managements of the aids to navigation.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 59 REFERENCES
[1]
Code for Acceptance of the Marine Aids to Navigation Efficacy, 2008
[2]
Wang, Y. Z. Aids to navigation. Dalian Maritime University Press. 1997(9).
[3]
IALA AIDS TO NAVIGATION GUIDE. China Communications Press. 2003(2)
[4]
Cai, W. Metter-elements model and application. Science and Technology Document Publishing
House. 1998.
[5]
Zhang, J. J. The study of aids to navigation efficacy quantitative evaluation. Master Degree Thesis
of Dalian Maritime University. 2004(3).
[6]
Xu, C. W. Study of the quantitative evaluation methods of technical risk of aids to navigation. Master
Degree Thesis of Dalian Maritime University. 2003(2).
[7]
Wang, R. Z. Aids to navigation efficacy evaluation of Yanda route. Symposium of Costal Aids to
Navigation Academic Exchange of Professional Committee of Aids to Navigation of Chinese
Institute of Navigation. 2005(10), 19-24.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 60 New Solid State Frontier on Radar Technologies Felicia Amato, Michele Fiorini, Sergio Gallone and Giovanni Golino, Rome, Italy ABSTRACT
Traditionally “solid state” is associated with Air Traffic Control (ATC) radars while tube technologies are
synonym of Vessel Traffic Service (VTS) and Homeland Protection (HP) radars. This historical division was
based on the fact that the transmitted spectrum and dynamic resolution of solid state transmitters (TX)
were not appropriate for VTS and HP applications.
Actually solid state technologies is now mature to remove the above limitations. The LYRA 50 series
thanks to a fully solid state architecture gains coherent signal processing, low transmitting peak power, low
voltage supply, high compactness, high reliability and capability of transmission on multiple frequencies.
In the LYRA radar family Wideband Frequency Modulation (WFM) is used to minimise the electromagnetic
compatibility impact and is helpful in reducing interference from other radiating systems. The joint use of
multi-frequency diversity and pulse compression –both digitally performed- allows low peak power long
pulses, while a proprietary side lobe suppression algorithm reduces the pulse compression side lobe and
its time stability at different environmental conditions is obtained by calibration algorithms.
This paper also shows results collected during the performance evaluation campaigns of the LYRA radar
family and a demonstration of the achieved operational benefits on-live traffic recordings.
Keywords: solid state, pulse doppler radar, pulse compression, multi frequency diversity.
RÉSUMÉ
Le terme « solid state » est traditionnellement associé aux radars de contrôle du trafic aérien, alors que les
technologies « tube » sont synonymes de services de trafic maritime (STM) et de protection du territoire.
Cette division historique est basée sur le fait que le spectre transmis et la résolution dynamique des
émetteurs solid state ne sont pas adaptés au STM ni à la protection du territoire.
En réalité la technologie solid state est maintenant suffisamment mature que ces limites disparaissent. La
série LYRA50, grâce à une architecture entièrement solid state, offre un traitement du signal cohérent, une
faible puissance de crête, une alimentation en basse tension, un faible encombrement et la capacité
d’émettre sur des fréquences multiples.
Dans la famille des radars LYRA la modulation de fréquence en bande large (WFM) est utilisée pour
réduire l’impact sur la compatibilité électromagnétique ; elle est aussi utile pour minimiser les parasites
d’autre systèmes émetteurs. L’utilisation conjointe de la diversité multi-fréquence et de la compression de
pulsion – toutes deux réalisées électroniquement – permet des pulsions longues à faible puissance de
crête, pendant qu’un algorithme de suppression des lobes latéraux réduit la compression d’impulsion et la
stabilité dans le temps dans différentes conditions d’environnement est obtenue par calibrage des
algorithmes.
Ce rapport montre aussi les résultats obtenus pendant les campagnes d’évaluation des performances de la
famille des radars LYRA et démontre les avantages opérationnels obtenus sur des enregistrements de
trafic en « live ».
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 61 1.
GENERAL DESCRIPTION
The commercial technology is nowadays mature for supporting the development of a low cost radar family
that can be adapted for different tasks.
The LYRA radar family joins synergically the enhanced capability of actual commercial technology with the
need for high performance radars: advanced processing algorithms can now be integrated in modern, low
cost and compact sensors.
The design guidelines of LYRA radars are:
•
transceiver coherency;
•
fully solid state technology;
•
low power emission;
•
high compactness.
In particular, LYRA 50 brings this approach to VTS radars. Classical VTS radars are non coherent, high
peak power radar; while LYRA 50 is a pulse-Doppler radar transmitting low power wideband coded pulses.
The low power emission is counterbalanced by the use of advanced techniques such as:
•
Digital Generation of Wideband Waveforms (WWG);
•
Digital Pulse Compression (DPC);
•
Doppler Filtering (Moving Target Detector / MTD);
•
Adaptive thresholds for target detection (CFAR, clutter maps);
•
Transmission of pulses on different frequencies.
A functional block diagram of radar is shown in fig.1. LYRA 50 uses Digital Direct Synthesis (DDS) to
generate Wideband Frequency Modulated waveforms (WFM). The combined use of WFM and DPC
enables the transmission of low power long pulses: an effective pulse with short length (assuring high
range resolution) and high peak power (reaching the desired coverage) is obtained by the compression of
the echoes with fine calibrated digital filters (containing the side lobes [1]). In particular, high range
resolution improves the super-clutter visibility and enhances the capability of detecting small boats. WFM
antenna:
also increase the electromagnetic
slotted waveguide
compatibility and is helpful in reducing
RF (X-band)
B=22 MHz
interference from other radiating systems.
LYRA 50 coherence permits clutter reduction
by means of a Doppler filter bank. In
particular, it enhances the radar detection
capability in presence of precipitations. The
environment interference counteraction is
reinforced by the use of a programmable
digital STC (Sensitive Time Control) and by
the automatic adaptation to the environment
of the detection thresholds by CFAR
techniques (Constant False Alarm Rate) and
clutter maps.
TX solid state
UP
Converter
frequency selection
(200 MHz bandwidth)
DFS
Front
End
WWG
(WFM)
RF (X-band)
RX
WWG: Wideband Waveform Generator
WFM: Wideband Frequency Modulation
DFS: Digital Frequency Synthesizer
DDC: Digital Down Conversion
DPC: Digital Pulse Compression
MTD: Moving Target Detector
CFAR: Constant False Alarm Rate
A/D
DDC
DPC
MTD
CFAR
MAPS
fc= 100 MHz
TRACKER&DISPLAY
DATA
EXTRACTOR
Alignment&
integration
Fig. 1. LYRA 50: block diagram. 17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 62 LYRA 50 multi-frequency transmission is realized by DFS (Digital Frequency Selection) and wideband
technology: it enhances the coverage capability by reducing the fluctuation loss of the target echoes and
decreasing the correlation of the clutter returns.
Most of these features are possible because of the substitution of the magnetron final amplifier with a more
flexible solid state device. In the following section the difference between these two different technical
solutions are detailed.
2.
FULLY SOLID STATE TRANSCEIVER
The employment of solid state in VTS radars introduces a lot of technical novelties that could bring
to a renewal of the standards and the recommendations of such systems.
Classical VTS radars use magnetron as final amplifier. Magnetron transmitters can be appealing for their
high transmitted peak power and contained cost, but have several drawbacks:
•
small operational life (needs to be replaced during the year);
•
non coherent processor: phase coded waveforms and Doppler filtering is not allowed;
•
low duty cycle (up to 0.1%);
•
fixed frequency;
•
high voltage supply (order of tens of KVs).
On the contrary fully solid state final amplifier brings the following benefits:
•
long, failure-free life and graceful degradation of system performance;
•
coherent processing possible;
•
high duty (better than 10%);
•
frequency agility capability;
•
no high-power elements (simplification of operational, service, and maintenance requirements and
elimination of electric shock risk);
•
compact technology.
The efficiency of solid state technology is rapidly increasing and the power of single modules is growing [2,
3 and 4]. Magnetron can reach still much higher peak power (order of tens of Kilowatts in VTS application)
while the output power of a basic power-generating, solid state unit is in order of tens of Watts. However,
the average power required for reaching the desired coverage can be rescued by using more than one
module in parallel and by opportunely using the much higher duty.
The solid state transmitter allows the introduction of important techniques such as:
•
Wideband low peak power transmission, minimizing electromagnetic pollution;
•
Doppler processing, improving clutter rejection;
•
Frequency transmission covering a large bandwidth, which can improve target detection and
interference rejection.
These techniques are detailed in the following sections.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 63 3.
WIDEBAND FREQUENCY MODULATED WAVEFORMS
The transmitted waveform consists in a pair of pulses (short and long) with the following characteristics:
•
•
•
•
short pulse length 2.5 μs;
long pulse length 40 μs;
short pulse range 3.24 nm;
long pulse range 24 nm;.
The short pulse function is to constrain the blind range to 375 m. Both the pulses are LFM coded (Linear
Frequency Modulation) and have an instantaneous bandwidth of 22 MHz. The pulses are modulated and
compressed by the signal processor. The amplitude modulation realized by the compression digital filter
limits the range side lobes to PSLR=35 dB for the short pulse (fig. 2) and PSLR=42 dB for the long pulse
(figs 3-4). The nominal range resolution (the -3dB width of the compressed pulse main peak) is 9 m for both
pulses.
Fig. 2. Short pulse after digital pulse compression 4.
Fig. 3. Long pulse after digital pulse compression Fig. 4. Long pulse after digital pulse compression: close up around the main peak. DOPPLER PROCESSING
LYRA 50 has a bank of 4 Doppler filters. This feature improves detection boats capability in presence of
rain and sea clutter proportionally to the relative speed difference.
Using the output of the Doppler filters an estimation of the target radial velocity is also possible. That
information can be used for the improvement of tracking performances [5].
5.
MULTI-FREQUENCY TRANSMISSION
LYRA 50 can transmit up to 8 frequencies within a band of 200 MHz (9.2-9.4 GHz). Being the CPI
(Coherent Processing Interval) of the radar four pulses long, up to 4 different frequencies can be
transmitted during the ToT (Time on Target).
The transmission on different frequencies enhances the detection capability of the radar [6]. The overall
echo of a complex target such as a vessel is the combination of the echoes from several scattering
elements. The interaction between the echoes can be destructive decreasing the detection probability. The
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 64 frequency changing affects the interaction between the different scattering elements, reducing the
probability that the destructive effect can persist during all the ToT.
Statistic model of target RCS are used to estimate coverage performance [6]. Swerling 1 (SW1) model
supposes that the target has several comparable scattering sources and that the resulting overall echo
does not vary during the ToT. This model is generally used for estimating the performance of fixed
frequency radar in presence of naval targets. Swerling 2 model (SW2) considers as SW1 a target with
several comparable scattering sources but in this case the result of the scatterer interaction varies from
pulse to pulse without any correlation. This variation can be obtained by a opportune variation of the
transmitted frequency.
The coverage performance in presence of SW1 targets takes into account the event of the destructive
combination by a virtual loss in sensibility, the so called fluctuation loss (i.e. 8 dB if Pd=90% and Pfa=1e-6
are required). SW2 targets has smaller fluctuation loss so the transmission on different frequencies partially
recovers that loss.
Figs 5 and 6 show the detection probability for the model SW1, SW2 e Swerling0 (no fluctuation loss):
In a similar way, transmission on different frequencies can decrease the negative effect of clutter
interference. The combination of the echoes due to the clutter can be in the worst case constructive and
transmitting multiple frequencies can decrease the probability that such unlucky event persists during all
the ToT. Frequency agility is especially effective in the case of rain clutter, where the number of scattering
source is high.
With a slotted waveguide antenna such as the LYRA 50 one, multi-frequency diversity brings an additional
profit. This radiating system presents an azimuth squint with frequency that is digitally compensated by the
signal processor. The squint of the beam increases the time difference between the frequency agile pulses
and reduces the probability that strong echoes from sea spikes persists during all the ToT.
Fig. 5. Detection Probability as function of the Signal to Noise Ratio; non coherent integration of 2 pulses; different target fluctuation models. 6.
Fig. 6. Detection Probability as function of the Signal to Noise Ratio; non coherent integration of 4 pulses; different target fluctuation models. LYRA FAMILY
LYRA is a family of radars: the same hardware and software core has been used and modified to execute
different tasks.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 65 cars
40 m
30 m
5m
person
25 m
cars
Fig. 7. LYRA 10 live data (December 2006): detection and discrimination of cars and people. For example slowing the antenna rotation rate, high Doppler
resolution can be reached and it can be coupled with high
range resolution. In such configuration, LYRA 50 could
discriminate, if digital processing is properly modified, slow
moving targets on the ground like humans or vehicles from
land clutter and perform their detection on a terrestrial
background.
The radar LYRA 10 is based on this principle. Figure 7 is an
example of results obtained with LYRA 10. In an limited area
of few tens of square meters different targets are revealed (5
cars and one walking person).
Moreover, an high Doppler resolution radar as LYRA 10 is
also appealing for maritime surveillance and can introduce in
the system extra features such as the capability of
instantaneously detecting any movement of the buoys and
aids to navigation.
7.
RADAR LIVE DATA
(GULF OF ADEN)
LYRA 50 is operative in Yemen,
and it has been integrated in
the NYVP system (National
Yemen VTS Project).
Two radars are located in Aden
area, an important high traffic
harbour controlling the route
from Europe to Far East. Aden
is an interesting scenario for
testing the detection and
discrimination capabilities of
LYRA 50, because the radars
can monitor the movements of
the local fishermen, that use
small wooden boats (see fig. 8)
that tend to concentrate in
offshore fishing areas. The
radar can provide useful
information for the location and
control of such areas.
Fig. 8. Picture of a fisherman wooden boat (Gulf of Aden). Figure 9 shows a PPI capture
near the sunset, when fishermen come back to the shore and tend to navigate side by side. Fig. 10 shows
two small boats discriminated by the radar that are separated of about 30 m.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 66 2
m
=1
9
ΔX
4
=2
ΔR
m
1
1
Fig. 9. LYRA 50 live data (June 2009): section of display with fishermen small boat plots. 8.
2
Fig. 10. LYRA 50 live data (June 2009): section of the display with discrimination of close boat plots. CONCLUSIONS
In this paper LYRA 50, a novel fully solid state radar for VTS applications, has been presented, focusing on
the new capabilities and the performance improvement connected with the employment of a final solid state
amplifier. Example of live data from the operative radars in Yemen are also shown. A fully solid state radar
architecture is a very promising solution for the VTS application, thanks to the decresing cost and the
improvement in technicalogy of X-band high power solid state modules.
REFERENCES
[1]
Gallone S., Golino G., “Cancellation of Range Side Lobes due to the Analogue Section Distortion in
Radars using Digital Pulse Compression”, IRSI 2007.
[2]
Gregers Hansen V., “Radar systems trade-off vacuum electronics vs. solid state” Vacuum
Electronics Conference 2004, IVEC 2004, 5th IEEE International.
[3]
Brookner E., “Solid state and Vacuum Electron Device (VED) Radars – Past, Present and Future”,
Vacuum Electronics Conference 2006, IVEC 2004, 6th IEEE International.
[4]
Aethercomm engineering team, “Gallium nitride (GaN) microwave transistor technology for radar
application”, International Radar Symposium India (IRSI) 2007.
[5]
Farina A., Pardini S., “Multiradar Tracking Using Radial Velocity Measurements”, IEEE Trans. On
Aerospace, July 1979.
[6]
Skolnik M.I., “Radar Handbook 3rd edition”, 2008.
17th IALA Conference 17ème Conférence de l’AISM Le Cap, Afrique du Sud, 22‐27 mars 2010 Cape Town, South Africa, 22‐27 March 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Page 67 New Technology Radars and the Future of Racons N. Ward & M. Bransby, General Lighthouse Authorities, Research & Radio Navigation Directorate, UK, and R. McCabe & C. Day, Commissioners of Irish Lights, Ireland BIOGRAPHIES
Dr. Nick Ward is Research Director of the General Lighthouse Authorities of the UK and Ireland, providing
technical and policy support in all areas of research & development, including radar aids to navigation He is
currently vice chairman of the IALA e-Navigation Committee and was closely involved with the international
standardisation of both DGPS and AIS. He is a Chartered Engineer, a Fellow of the Royal Institute of
Navigation and a Member of ION.
Martin Bransby is the Manager of the Research and Radionavigation Directorate of the General Lighthouse
Authorities of the UK and Ireland. He is responsible for the delivery of their project portfolio in research and
development in such areas as AIS, eLoran, eNavigation, GNSS and Lights. He is an Associate Fellow of the
Royal Institute of Navigation, and holds memberships of the Institute of Engineering & Technology, the US
Institute of Navigation and the International Loran Association.
ABSTRACT
IMO MSC79 resolution 192(79) removed the requirement, from 1 July 2008, for S-band radar to trigger
Radar Beacons. This was intended to encourage manufacturers to develop new types of radar; known as
New Technology (NT) radar.
The GLAs have conducted racon trials with an NT Radar fitted to CIL Tender Granuaile. The trials were
conducted in the Dublin Bay, Codling and Arklow areas of the Irish Sea, where there are a number of fixed
and floating CIL AtoNs fitted with different types of racon.
Trial results showed that:
•
the NT radar tested did trigger racons but at a significantly reduced range;
•
there were gaps in the racon responses;
•
responses at S Band can be obscured by land clutter;
•
some anomalous responses were observed with the NT radar;
•
responses were much clearer on an X band conventional magnetron radar than on the NT radar,
except at close range;
•
increased racon receiver sensitivity appears to restore much of the lost range with the NT radar.
This paper concludes that consideration should be given to modifying existing racons to improve their
response to NT radars. This would need to be done in consultation with racon manufacturers. Further trials
should also be carried out to confirm that the results obtained apply to other types of NT radar.
The results are made available to IALA, so that there is general awareness of the potential effect of NT
radars on racon performance and so that the strategic options can be discussed.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 68 RÉSUMÉ
La Résolution 192(79) du Comité de Sécurité Maritime de l’OMI a supprimé, à compter du 1er juillet 2008,
l’obligation pour les radars en bande S de déclencher les balises radar. Le but était d’encourager les
fabricants à développer de nouveaux types de radars, connus sous l’appellation « radar de nouvelle
technologie (NT radar).
Le Groupement des autorités de phares du Royaume-Uni et d’Irlande (GLAs) ont mené des essais de
racons avec un radar NT installé sur le baliseur Granuaile, des Commissioners of Irish Lights (CIL). Les
essais se sont déroulés dans la baie de Dublin, dans les zones Codling et Arklow en mer d’Irlande, où se
trouvent de nombreuses aides à la navigation fixes et flottantes du CIL, équipées de différents types de
racons.
Les résultats des essais ont montré que :
•
Le radar NT testé a déclenché des racons mais à une distance nettement réduite
•
Il y avait des vides dans les réponses des racons
•
Les réponses en bande S peuvent être masquées par l’écho de terre
•
Quelques réponses anormales ont été observées avec le radar NT
•
Les réponses étaient beaucoup plus claires sur un radar à magnétron traditionnel en bande X que sur
le radar NT, sauf à courte portée
•
Une sensibilité accrue du récepteur racon semble restaurer la plus grande part de la perte réalisée
avec le radar NT.
Le rapport conclut que l’on doit étudier la modification des racons existants pour améliorer leur réponse
aux radars NT. Ceci devra se faire en accord avec les fabricants de racons. D’autres essais devront aussi
être menés pour confirmer que les résultats obtenus s’appliquent à d’autres types de radars NT.
Les résultats seront communiqués à l’AISM pour faire connaître l’effet potentiel des radars NT sur les
performances des racons, et discuter des options stratégiques.
INTRODUCTION
IMO MSC79 resolution 192(79) (IMO, 2004) removed the requirement, from 1 July 2008, for S-band radar
to trigger radar beacons (racons). The removal of this requirement was intended to encourage the
development of low power, solid-state, cost-effective radars which used digital signal processing
techniques to mitigate display clutter associated with high-power magnetron based radars. These radars
have become known as “new technology” (NT) radars.
NT radars have become available which claim to trigger racons (Wade 2008), even with considerably
reduced output power. Such a radar has been fitted to the Commissioners of Irish Lights tender “Granuaile”
(CILT Granuaile)
In an earlier study (Norris, 2006) carried out on behalf of the General Lighthouse Authorities of the UK and
Ireland (GLAs), it was recommended that trials be conducted to establish empirically NT Radar
performance using currently available racons. The GLAs have conducted trials using Granuaile’s NT radar
with a sample of their current racon fit, which have a current nominal range of around 10-12 NM. This
paper describes the outcome of those trials.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 69 OBJECTIVE OF TRIALS
The purpose of the trials was to determine the performance of S band racons (2.9-3.1 GHz) with a
commercially available NT radar, compared with a conventional, magnetron-based X band radar (9.3-9.5
GHz).
TRIALS METHOD
The trials used different manufacturers’ racons, which exhibited different characters and were fitted on both
fixed and floating Aids-to-Navigation (AtoNs).
Two sets of trials were carried out, in March and December 2009. Some anomalous results observed in the
first trials were investigated and mostly eliminated in the second trials.
The stations observed were the Arklow Buoy, the Codling Lanby, the Kish Bank Lighthouse and the Dublin
Bay Buoy. In addition, racons were set up for the trials on the pier heads at Dun Laoghaire for the first trial
and at Wicklow for the second trial.
Where time allowed the racons were observed as the vessel approached and departed from them up to
their maximum operational ranges.
Performance in terms of clarity of response and ability to identify codes were recorded at approximately 1
NM intervals on both NT S Band and conventional X Band radars.
RACONS TESTED
Racon A on the Dublin Bay Buoy, was a relatively modern, integrated, solid state design.
Racon B on the Kish Lighthouse, was an old design, widely used, but no longer produced.
Racon C installed at Dun Laoghaire for the first trial and at Wicklow for the second was a more modern
solid-state version of B, but also no longer in production.
Racon D on the Codling Lanby was an old version (18 years old) of a racon still in production.
Racon E on the Arklow buoy was a relatively new design, not in general use by the GLA.
Racon F installed on Wicklow pier for the second trial was the modern version of D, with an expected 10 dB
improvement in receiver sensitivity.
All were frequency agile, dual band X & S racons, with side-lobe suppression enabled and proportional
response, where available.
ENVIRONMENTAL CONDITIONS
The weather during the first trial was generally clear, with light winds and sea-state 2-3, rising to 3-4 later.
In the second trial, winds were fresh to strong with sea state 5 and visibility reducing to 1-2 NM in frequent
rain showers.
RESULTS
In the first trials it was shown that the NT radar did trigger racons but at a significantly reduced range when
compared to the Granuaile’s magnetron-based X-band radar. This triggering distance was typically 4-5 NM
compared with 10-12 NM for the X-band.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 70 It was noted that there were gaps in the coverage. If an initial response was obtained at say 5 NM, this
might continue to be satisfactory until a distance of between 3 and 4 NM when the response disappeared.
Then at a distance of between 2 and 3 NM, the response was once again satisfactory. This was assumed
to be the result of interference between the direct and reflected signal from the sea surface (multipath) and
is in line with theory, but reduces the reliable range of the racon response to 3 NM. Although this is a
known problem, it did seem to be exacerbated in these trials.
The racon interrogating pulse of the trial NT radar is very short (typically 0.1μs) and the paint of some
proportional response racons was correspondingly short (typically 0.5 NM). This could lead to the racon
response being lost in clutter.
Some racons responded with a portion of the “paint” in front of the actual position of the racon. This could
mislead the mariner into thinking that the Racon is closer to the vessel than it actually is; therefore giving
potentially hazardous and misleading information.
One particular racon (Racon “D” at the Codling LANBY) gave a response which was offset in azimuth by
approximately 10° from the actual racon position. At other times, the response was radially displaced by 10
NM beyond the actual racon position. This particular racon gave its first correct response at only 2.5 NM.
Subsequent discussions with the manufacturer of this racon revealed that this unit was 18 years old and
not up to the latest specification. Therefore these results could not considered representative of this racon
type.
Racon “E” (unused by the GLAs before this trial) gave inconsistent responses to the radar’s interrogations.
For instance, an incorrect Morse code followed a “no response” condition after a power reset. A further
power reset affected the correct response form the racon. It was not considered that this response was
typical of the racon and CIL have now investigated power supply problems with the buoy and concluded
that these were the cause.
In the second trial two racons (F & C) were set up on the East Pier at Wicklow and were powered up
alternately for 3 minutes at a time. The Granuaile steamed eastwards to allow a clear view of the racons.
On the S Band NT radar racon F gave good returns out to 10 NM, apart from an apparent null at around 12 NM. However, the paint was spread out and sometimes hard to distinguish in the land clutter. There were
also some spurious responses, displaced by about 180˚ and some spoking at close range (0.5 NM)
possibly caused by reflected signals from the pier wall. The racon was picked up again at 10 NM on the
outbound leg from the Arklow, so this range seems to be repeatable. This compared with clear and
consistent returns on the X Band to 10 NM on the inbound leg, with a maximum range of 12 NM on the
outbound leg.
Racon C gave returns at S Band out to 5 NM, again with a null at 1-2 NM. The paints were also hard to
distinguish against the land clutter. On the X Band the returns were clear and easily distinguishable out to
10 NM and then again from 12 NM down to 9 NM (the closest point) on the outbound leg.
The Arklow buoy was fitted with the racon E, which had given incorrect responses in the previous trial. The
suspected power supply problems had been fixed and the returns on S Band were clear from 3 NM on the
approach and out to 3 NM on the outbound leg. This compared with clear and consistent returns on X Band
from 9 NM on the approach. On the outbound leg returns became faint at 5 NM, possibly as a result of
shadowing by the superstructure.
Racon D on the Codling Lanby had given returns displaced in both range and azimuth in the previous trial.
This time the S Band returns were picked up at 5 NM, but then lost again until 3 NM, after which they were
clear. On the outbound leg they were lost at 2.5 NM. The X Band was picked up at 7-8 NM, but there was a
null at 5-6 NM and returns were lost in clutter below 2 NM. On the outbound leg returns were good, once
free of clutter, out to 8 NM.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 71 The next racon observed was B on the Kish Lighthouse. This was visible on S Band at 5.3 NM, with a null
at 3-4 NM, then visible again down to 2 NM, when the vessel headed away. Returns disappeared at 3.5
NM on the outbound leg. On X Band returns were clearly distinguishable from 14 NM down to 3 NM when
they disappeared in clutter.
The last racon observed was A on the Dublin Bay Buoy. This came in at 4.5 NM on S Band and was clear
down to 2 NM, the closest point. On X Band returns were clearly distinguishable from 12 NM down to 2 NM.
DISCUSSION
Ideally racons should be able to respond at range at least equal to the primary AtoN; indeed, for buoys, the
racon range is generally greater than that of the light. In these trials, the Racon failed to do this at S Band,
presumably because of the low power of the radar. Even though a response was present, it was typically
25-30% of the currently published ranges for Racons.
Earlier manufacturers’ predictions indicated that the maximum range of Racon responses “is approximately
7NM” (Wade, 2008). The GLA trials show shorter ranges than predicted.
A Racon Plan prepared for the GLA (Ward, 2009) and an earlier GLA report on the future of Racons (Norris,
2006) set out options for the future of racons. Amongst these are modification of existing racons,
development of NT racons and replacement of racons by AIS. AIS has the drawback that it relies on
Global Navigation Satellite Systems (GNSS) for position reporting, whereas racons currently provide an
independent alternative to GNSS in providing identification of AtoNs. If AIS was used as a replacement for
Racons, then a suitable complementary, diverse and resilient back-up to GNSS would be required in times
of GNSS service denial. The GLAs maintain that the only way to provide resilient and robust positioning
systems is through the employment of a back-up to GNSS, using eLoran.
Modification of existing Racons would be the lowest cost option (Norris, 2006) and should be investigated
first. Development of NT Racons would be very expensive and would have to be carried out in conjunction
with industrial partners.
The performance of all the racons was much better on X Band than S Band, not just in terms of range, but
in clarity of response. The display of returns on the NT S Band radar was spread out and this made the
racon paints more difficult to distinguish and identify, particularly in land clutter. The only exception was at
close range, when the X Band response tended to be lost in sea clutter. Rain clutter also obscured the X
Band returns.
The ranges at S Band were generally 5 NM or less, with the exception of the racon F a new version of
racon D, which gave 10 NM. This is consistent with the manufacturers estimate that the receiver sensitivity
of the new version would be 10 dB greater than the older version. Ranges on X Band were generally 8-12
NM, depending to some extent on the height of the platform.
The anomalies experience in the earlier trials appeared to have been largely resolved in the later trial.
However, it should be emphasised that these results were obtained with one particular type of NT radar.
There are others on the market and these could give different results. Trials would be needed with other
types to determine whether the conclusions drawn can be applied generally.
CONCLUSIONS
1. The NT Radar tested did trigger racons, but at substantially reduced range (less than 5 NM).
2. A new version of one of the racons tested did give up to 10 NM range at S Band, almost certainly
because of its improved receiver sensitivity (+ 10 dB).
3. The inconsistencies in responses of some racons in the first trial, were resolved.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 72 4. The ranges with a conventional X Band radar were generally much better, around 10 NM and clarity of
response was much greater, except at close ranges in clutter.
RECOMMENDATIONS
1. Modification of existing racons to improve their response to NT radars should be considered in
consultation with racon manufacturers. Modifications could include: increasing the receive sensitivity,
removing the scalable response, designing the racon to detect, and respond differently to NT radar.
2. The differences in racon performance during these trials indicate that better standardisation of racons
should be considered.
3. IALA should be invited to consider the results of these trials when discussions its startegy for the future
of racons.
ACKNOWLEDGEMENTS
The authors wish to acknowledge the cooperation and support of the Captain and crew of the CIL Tender
Granuaile, the assistance and organisation provided by Captain Robert McCabe and the CIL Engineering
Department. The participation of Capt. Roger Barker (THLS) and Peter Douglas (NLB), the NT radar
manufacturer and consultant Prof Andy Norris in the first trial was also very valuable.
REFERENCES
1.
IMO (2004) “Adoption of the revised performance standards for Radar equipment.” Resolution
MSC.192(79).
2.
Wade, B. (2008) “Triggering Racons by Solid State Radar.” 29 December 2008
3.
Norris, A. (2006) “The future of Racons.” Report for the GLA, Navigation Systems Consultancy,
2006
4.
Ward, N. (2009) “The R&RNAV Racon Plan.” General Lighthouse Authorities of the UK and Ireland,
2009
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 73 A Next Generation Solid State, Fully Coherent, Frequency Diversity and Time Diversity Radar with Software Defined Functionality Jens Chr. Pedersen, Director, Product Portfolio & Innovation, Radar Systems, Terma A/S, Denmark ABSTRACT
Coherent, Solid State Radar technology has been available for military applications for decades, but it did
not penetrate into VTS for cost and technical reasons.
Technically, the main challenge has been that the dynamic requirement to VTS radar is much higher than
to other radar applications. However, new radar technology, virtually unrestricted by dynamic constraints,
has now been developed and is in operation for military applications.
To make this affordable for VTS and other applications for professional users, well-renowned advantages
and new functions are implemented on a new technology platform. Methods are further refined and the
outcome is software defined radar series, tailored to individual market segments and featuring:
• Even smaller targets detection
• Improved resolution
• Improved Frequency Diversity
• Even better all-weather processing capability
• Sub-clutter visibility for targets moving radially and having speeds different from clutter
• Easy system configuration and integration into systems of systems
• Substantially reduced requirements to maintenance
The new technology includes faster processing than ever, novel low voltage - low temperature (long life)
solid state transmitters, enhanced receiver technology, very high speed coherent sampling on IF, floating
point representation of data, low time-sidelobe pulse compression, loss-free signal processing and several
other improvements.
RÉSUMÉ
Une technologie cohérente de radars solid-sate est utilisée pour les applications militaries depuis des
décennies, mais elle n’a pas jusqu’à maintenant pénétré dans le domaine des STM pour des raisons
financières et techniques.
Techniquement, le principal défi est que les exigences dynamiques pour le radar STM sont beaucoup plus
grandes que pour les autres applications radar. Cependant, une nouvelle technologie radar, qui n’est
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 74 théoriquement pas limitée par des contraintes dynamiques, a maintenant été développée et fonctionne
dans des applications militaires.
Afin de la rendre abordable pour les STM et autres usagers professionnels, des avantages reconnus et de
nouvelles fonctions sont mis en place sur une nouvelle plate-forme technologique. Les méthodes sont
affinées et le résultat prend la forme d’une série de radars définis par logiciels, adaptés aux différents
secteurs du marché et présentant les caractéristiques suivantes :
•
La détection de cibles plus petites
•
Une plus haute résolution
•
Une diversité de fréquences améliorée
•
Une meilleure capacité de traitement par tous les temps
•
Une visibilité sous-écho pour des cibles se déplaçant « en étoile » à des vitesses différentes de l’écho
•
Une configuration de système simple et une intégration aisée dans un système de systèmes
•
Un besoin en maintenance considérablement réduit.
Cette nouvelle technologie comprend un traiement plus rapide qu’avant, des émetteurs solid-state à basse
tension et faible température (vie plus longue), une technique de réception améliorée, un échantillonnage
extrêmement rapide et cohérent sur une fréquence intermédiaire, une représentation à virgule flottante des
données, une compression, une compression en temps restreint des impulsions des lobes latéraux, un
traitement du signal sans perte, et beaucoup d’autres améliorations.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 75 The SCANTER 5000 and SCANTER 6000 series comprise a new generation of Fully Coherent, Frequency
Diversity and Time Diversity, Solid State Radars with Software Defined Functionality for professional
applications such as VTS, Coastal Surveillance, Airport Surface Movement Radars (SMR), and Ships.
Figure 2: 8x8 nautical miles section of radar image, heavy rain showers and strong SW wind. 4 sub bands in use, 3 m range cell size, 2 W (average) radiated power. Cross section (A‐scope) of fast ferry inserted, lower right. In order to extend lifespan of the most critical part of the new design, the Solid State Power Amplifier
(SSPA), several new developments have been realized. This includes low voltage, low temperature,
microwave power generation with efficient temperature management, and graceful degradation capability.
Extremely high resolution with small range cell size and high pulse compression factors has been achieved
utilising 32-bit floating point calculations throughout the signal processing chain, providing lossless
processing virtually unrestricted by dynamics. Target definition is in excess of that seen before and which
results in high definition radar images as illustrated in Figure 2.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 76 Frequency Diversity and Time Diversity are standard features for the new series of radars. Application
specific features include dedicated set-up and processing, support for helicopter guidance, and embedded
automatic target tracker.
Figure 3. Radar system configuration A complete radar system is illustrated in Figure 3. The transceiver acts as the central system component
configured with plug-in modules. Peripheral units are added as required by the individual application.
Communication as well as signal and track distributions are preferably provided on single or redundant IP
network. Additional serial communication lines are available for easy integration into new or existing
systems of systems. The video outputs are available in both analogue, digital and IP network formats.
PERFORMANCE
The new radar series has been designed to comply with IMO, ICAO and IALA V-128 requirements and
recommendations.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 77 Performance exceeds the advanced examples in IALA V-128 by arbitrary 20% for a radar in the most
powerful 200 W configuration. This is of course subject to physical constraints such as atmospheric
propagation and the curvature of the earth.
Discrimination between classes of compliance to IALA V-128, Basic, Standard and Advanced capability will
only be dependent on the antenna selected. In any case, the new radars are superior in respect to range
resolution and performance in adverse weather.
In cases where less transmitter power is sufficient with respect to target range detection a 50 W amplifier is
available, thus reducing cost.
In general a radar primarily relying on Doppler information will appear as unreliable in respect to detection
of surface targets due to target tangential movements and clutter speeds. Therefore it was decided to
provide MTI as an add-on feature, as all the pertinent applications require good normal radar performance.
Utilisation of the Doppler shift can be added as a plug-in feature to enhance air target detection and in
cases, where added performance is required for the detection of small surface targets moving radially
towards or from the radar - and with speeds different from clutter.
CONCEPTS
Basically two concepts are available for solid state radar technology: Pulse Compression and Frequency
Modulated Continues Waves (FMCW).
The benefits from FMCW are lowest peak transmitter power and easily obtainable short range
performance. However, in applications with both small and large targets, at both short and long ranges, it is
extremely difficult to obtain sufficient dynamic properties, because transmission and reception take place at
the same time. For such applications FMCW would in any case call for two antennas, one transmitting and
one receiving.
Equivalent
compressed
power
Power
Chirps
transmitted
Transmitter
Time
Antenna
Power
Receiver /
Processing
Echo
Time
Time
Figure 4. Pulse compression. Long weak received chirps are converted into short powerful pulses on reception Pulse compression radars are better suited for applications requiring high dynamic range, and the
utilisation of pulse compression is logically the right method for making an affordable and well performing
solid state radar for the applications in question. Another benefit of using pulse compression is that existing
antenna technology is maintained.
Therefore, pulse compression was selected for the new series of radars. Up to 100 micro second (15 km in
length) chirps are pulse compressed to few meter long pulses as illustrated in Figure 4.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 78 SOFTWARE DEFINED FUNCTIONALITY
A variety of radar signal processing techniques are available to meet increasingly difficult challenges, and
the entire processing structure of the new radar series is defined by software. Functions relevant for the
individual application are invoked as appropriate.
For example, it is possible to switch between different modes of operation by modifying both the
synthesized transmit waveforms and receive signal-processing tasks, even on the fly.
See Figure 5 for an example of a transmission sequence involving three pairs of transmitted chirps. Six
different frequencies are simultaneously in the air.
Long
chirps
Medium
chirps
Short
chirps
Time
Transmit
Etc.
Receive
Transmit
Figure 5: Example of transmission sequence FREQUENCY DIVERSITY AND TIME DIVERSITY
The Frequency Diversity and Time Diversity concepts from previous products were virtually unchanged, but
implemented in software.
Firstly, the fluctuation of desirable targets is reduced by illumination with two or more frequencies, thereby
enhancing targets relative to clutter.
Secondly, for a linear array antenna different frequencies are transmitted in different angles (the angle
difference is the squint). Together with a rotating antenna this provides for the Time Diversity enabling
suppression of clutter returns whilst maintaining signal from targets virtually unchanged.
The return signals, corresponding to identical
antenna directions, are combined using
proprietary operations. The difference in squint
and timing between the frequencies applied is
corrected by alignment in range and in
azimuth.
Full benefit from the Frequency Diversity
technique is obtained by maintaining dynamic
characteristics and automatically adapting to
actual weather and clutter situations. The
sensitivity is therefore matched to the actual
clutter levels, providing optimum detection at
all ranges and in all directions.
Rotation
F1 t +
0
t
Squint angle
F1 t
0
F2 t +
0
SOLID STATE
t
F2t
0
Figure 6 Frequency Diversity and Time Diversity concept Solid State means that electrons move in
solids rather than vacuum (tube). The Solid-State Power Amplifier (SSPA) for the new series of radars is
based on state-of-the-art microwave transistors. Several transistors are integrated into Power Amplifier
(PA) modules, each amplifying the signal and producing ≥ 50W of microwave power. The output power
from numerous modules is combined as illustrated in Figure 7.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 79 PA module
MMIC
MMIC
Figure 7: Microwave Transistor and 200 watt SSPA with 4 PA modules The major advantage from Solid State is that there is no need for periodic replacement of components as
required when using magnetrons or other tube transmitters. In addition, the high voltage supplies used in
former technologies are replaced by low voltage power supplies.
It is commonly assumed that Solid State transmitters are virtually maintenance free and that logistic
support is like computer electronics. However, the component count in Solid State amplifiers tend to be
much higher than in former technologies, and instead of high voltages, high currents are required to
produce sufficient output power.
Figure 8 Free space range and power vs. power transistor failure High currents generate heat, and the semiconductor materials used are poor heat conductors by nature.
Each 8-10 degree increase of internal MMIC temperature will double the failure rate of such components,
and “thermal run-away” used to be a common problem. High reliability does therefore call for special design
measures. The lifetime of an amplifier is consequently always highly dependent on the environment in
which it operates.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 80 In order to meet these challenges a number of novel techniques are utilised for the new series of radars.
The tendency to “thermal run-away” has been eliminated by a brand new generation of transistors.
Furthermore, the gain of the individual component is high, requiring fewer amplifier stages - and thereby
less component count.
In addition a new thermal management concept has been developed, involving efficient heat removal from
the individual transistor.
Finally, careful integration of several transistors ensures SSPA soft failure in the event of a loss of one or
more individual transistors. Consequently, loss of a single or few components will only result in marginal
drop of output power performance. In addition, the loss of a pair of transistors is reported by the BITE
system. It is therefore feasible to allow for the loss of one or more defective transistors and postpone
replacement until convenient.
Figure 8 illustrates the relation between loss of transistors, power and free space range performance of the
individual radar. Note that the free space range performance assumes line of sight from radar to target and
excludes any influence from propagation, clutter or precipitation.
SECTOR POWER TRANSMISSION
The transmitter power level can be controlled in sectors as
illustrated in Figure 8. This will reduce the implications of
spectrum pricing now starting to emerge in some
countries. In combination with the ability to select
subbands for transmission, it will also increase robustness
against interference between radar stations.
The power is adapted to that needed in sectors, reducing
undesirable illumination of e.g. populated areas,
eventually reducing the cost of spectrum pricing and
further enhancing lifetime of the SSPA’s.
The receiver will automatically adapt to varying power
levels, giving undisturbed images to the radar operators.
Figure 9: Sector Power Transmission FUNCTIONAL DESCRIPTION
The transmitted signals consist of frequency modulated chirps with up to 16 sub-band carriers.
Referring to Figure 9, transmission sequences are synthesized, passed through the SSPA, and directed to
the antenna via the circulator. Returned echoes from the antenna are directed to the receiver by the
circulator.
The receiver sensitivity is dynamically controlled in range, in azimuth and over time, and optimum signal to
noise performance is ensured by low noise amplifiers. A limiter providing swept gain on RF, combined with
receiver protection, provides part of the sensitivity adjustment.
After down conversion in the receiver the signal is sampled on IF level with 14 bit at very high speed,
demodulated, pulse compressed and (if included) processed to utilise the Doppler shift. The video is
converted to logarithmic formats and forwarded for display and tracking through the
FiveStepVideoPassing™. Highly advanced proprietary processing techniques provide normal video and,
depending on application, Doppler processed (MTI) video.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 81 Integrated BITE functions perform continuous monitoring of the
radar during start-up and operation. This includes temperatures,
voltages, signal activity, key performance parameters etc. The
receiver noise figure, forward and reverse power are used for
performance monitoring.
Antenna
Solid state
transmitter
32 bit floating point representation of data ensures virtually
unrestricted dynamic characteristics, and the new technology
leads to very high resolution at all ranges.
Receiver
IF signals
Phase and amplitude
Reference
(phase and amplitude)
A/D
conversion
Synthesis
Demodulation & pulse compression
Up to 32768 range cells with size from 1.5 to 6 meters are
employed. Corresponding capabilities and constraints are shown
in Table 3.
Several other parameters are linked to the figures, and
configuration of the individual radar station is made within those
limits. The overall maximum instrumented range is limited to <
100 nautical miles by software.
Embedded tracking is provided as a plug-in module, making
plots and tracks available on the IP network.
MTI *
* Optional or add-on feature
Signal Distribution and control of the radar are preferably
performed via IP network, alternatively in analogue, digital or
serial data line formats.
FiveStepVideoPassing™
Embedded
tracker *
IP
network
video
Digital /
analogue
video
Digital and analogue video
Serial communication ports
Auxiliary I/O
Tx inhibit
Range cell size, meters
Number of (FFT) range cells
I/O
management
I/O
Table 3 IP network
Network video
Plots and tracks
Control, monitoring, setup
AIS and map interface
*
*
Figure 10 Functional Block Diagram Max instrumented range [nmi]
Corresponding resolution (target
range separation) [m]
1.5
3
6
32768
32768
32768
26.5
53.1
100.0
<9
< 12
< 18
Airport SMR applications will normally utilise 1.5 or 3 meter
range cell size. VTS, Coastal Surveillance and Ships
Surveillance radars will normally utilise 3 or 6 meter range cell
size.
PROCESSING
The main purpose of the signal processing is improvement of the signal to clutter ratio, and various means
utilise the statistical and speed properties of targets and clutter with signal speed dependent signal to
clutter improvements as illustrated in Figure 11.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 82 Figure 11 Clutter reduction techniques The processes include automatic adaptation to the environment. Smart channel combiner and interference
filtering suppress asynchronous interferences and second/multiple time around returns, as staggered
transmission sequences are used.
Auto adaptive parameter settings are used in the filters, in the Frequency Diversity combiners and in the
integration process to omit beam shape and other losses as well as to optimize sensibility.
For surface radar applications, the utilization of Doppler information is substantially different from the
techniques used for air surveillance:
¾ Speed differences between targets and surroundings are much smaller, and discrimination is therefore
less efficient
¾ Targets of interest on the surface will often move tangentially or with low radial speed for prolonged
periods, and in such cases they will be completely suppressed
¾ Most small surface targets have radar cross sections virtually independent of their aspect angle.
Therefore large echoes cannot be expected for small tangentially moving surface targets.
Surface surveillance radars relying too much on Doppler information may therefore appear as unstable in
operation and detection. Consequently, the new radar series utilises basic detection of surface targets
based on non-Doppler processed (Normal Radar) signals.
Supplementary utilization of Doppler processed signals for detection of surface targets is added in
applications, where additional performance can be obtained. The best of that detected in the two channels
is automatically selected. An intelligent combination of the two channels is forwarded for presentation and
tracking.
On moving platforms, the processing is compensated for own unit movements.
The speed and propagation movement direction of clutter is in all applications automatically determined
using Terma proprietary algorithms.
SIDE LOBE SUPPRESSION
By nature, pulse compression will create time side lobes in a radar image. These are imperfections in
range, where a target will appear with “artificial” targets before and/or after the actual target. A similar
effect, due to antenna characteristics, can be seen in azimuth and is called antenna side lobes.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 83 Side lobes are unwanted, as they will limit the size of a small RCS target that can be detected next to a
large RCS target. The ratio between the peak level of the target and the highest time side lobe is called the
Peak Side Lobe Ratio (PSLR).
Traditionally, time side lobes may be a severe limitation in pulse compression radars. However, a new
proprietary approach that overcomes this has been developed. The result is that time side lobes are
reduced by more than 60 dB.
Traditional radar.
Unwanted side lobes
Terma radar.
Clean target echo
Time side lobes
Target
Target
Antenna side lobes
Figure 12 Poor versus good side lobe behaviour INFLUENCE FROM WIND TURBINES
Wind turbines are known to give adverse effects on radars, in the form of false targets and/or reduced
radar sensitivity.
The large vertical extent of the wind turbine generators return radar responses strong enough to produce
interfering side lobe, multiple and reflected echoes (ghosts). The rotating blades produce returns with wide
spread in the Doppler spectrum, strong enough to jeopardize detection of moving targets in radars utilizing
the Doppler shift.
Calculation of the radar cross section showed that an individual wind turbine has a radar cross section of >
50 dBm2 (> 100.000 square meters) in X-band, whereas the rotor may have an RCS in the order of 30
dBm2 (1.000 square meters)
In the new series of radars the effects are minimized by:
¾ High resolution and a separate normal (non-MTI) channel. This is providing even better performance
than traditional non-coherent (magnetron) radars in areas with wind farms.
¾ High dynamic range, preventing saturation from strong returns.
¾ Efficient antenna and time side lobe suppression.
¾ Special processing, omitting disturbance in the vicinity of wind farms.
¾ In the case of utilisation of the Doppler information, good sub-clutter and especially very good interclutter capabilities in the MTI channel. The “best off” the MTI and non-MTI is automatically selected for
display and tracking.
In summary, the radar provide “best in class” performance in wind farm areas.
Note that the elimination or reduction of ghost echoes almost entirely depends on the physical location of
radars relative to the wind farms, targets and other reflecting structures. One alternative exists being the
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 84 utilization of more than one radar covering wind farm areas, combined with processing, taking signals from
more than one radar into account.
Wing tip
Figure 13 Offshore wind farm and Radar image from row of wind turbines, 3 meter range cell size PRECAUTIONS AGAINST INTERFERENCE
By nature any radar employing Pulse Compression or FMCW will be more subject to interference than
traditional pulsed radar. It is furthermore necessary to transmit chirps with different lengths to obtain
simultaneous short and long range coverage, and there is a risk of e.g. RACON’s being displayed in wrong
positions if such chirps are not efficiently separated.
Calculation shows that as much as 80 dB isolation between individual chirps is needed. This leads to the
concept of sub-bands, and it was decided to implement 16 individually programmable sub-bands in the new
radar series.
In addition to making the radars very robust against interference and malfunctioning, it will also eliminate
traditional problems with 2nd time around returns and make the radar easily adaptable to any local or
national restrictions in respect to utilization of frequency bands.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 85 Four‐Season Lighted Buoy Development Développement d’une bouée lumineuse quatre saisons Richard Moore, Canadian Coast Guard – Garde côtière canadienne ‐ Canada INTRODUCTION
INTRODUCTION
Aids to Navigation service delivery in Canada is
complex and costly due to the size of the Country
and particularly harsh winter conditions.
Au Canada, la prestation d’un service d’aides à la
navigation est complexe et coûteuse en raison de
l’étendue du territoire mais aussi en raison des
conditions particulièrement sévères qui sévissent
en hiver.
The situation on the Saint-Lawrence River, in
Eastern Canada, presents additional challenges
due to its waterway being open all year-round to
commercial traffic and to severe environmental
conditions.
The aim of this project is to help the Canadian
Coast Guard (CCG) reduce pressure on its vessel
operations and eventually reduce its operating
costs.
CONTEXT
Shipping on the Saint-Lawrence River is an
important element of the Canadian and US
La situation du fleuve St-Laurent, situé dans la
province de Québec dans l’est du Canada, pose
des défis supplémentaires en raison de sa voie
navigable ouverte à l’année à la navigation
commerciale et à des conditions
environnementales particulièrement exigeantes.
Le projet présenté ici vise notamment à permettre
à la Garde côtière canadienne de réduire la
pression sur ses opérations de navires et
éventuellement, réduire ses coûts d’opération.
Canada
Montréal
USA
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 86 economy. The Saint-Lawrence serves as a
waterway connecting the Atlantic Ocean to the
Great-Lakes and provides commercial ships
access to more than 3,700 kilometres inside the
North-American continent. Half of the 20 major
Canadian ports are part of the Saint-Lawrence –
Great-Lakes Network, where a total of 200 metric
tonnes of cargo were handled in 2005 with over
27,000 ship movements.
CONTEXTE
La navigation sur le fleuve est un élément
important des économies canadiennes et
américaines. Le fleuve sert de lien maritime entre
l’océan Atlantique et les Grands Lacs, donnant un
accès aux navires commerciaux à plus de
3700 km à l’intérieur du continent nord-américain.
La moitié des 20 plus importants ports du Canada
font partie du réseau du fleuve St-Laurent et des
Grands Lacs. Le total du fret manutentionné
dans les ports de ce secteur totalisait près de
200 millions de tonnes métriques en 2005 avec
plus de 27000 mouvements de navires.
Des villes aussi éloignées de l’océan que
Chicago, Duluth, Cleveland et Détroit aux
États-Unis ainsi que Thunder Bay, Sault SteMarie et Toronto au Canada bénéficient d’un lien
maritime direct avec l’étranger. C’est le chemin
le plus court pour relier deux des zones les plus
industrialisées du monde : l’Europe et le centre
de l’Amérique du Nord.
Winter Navigation Exemple de navigation hivernale Cities as far inland as Chicago, Duluth, Cleveland
and Detroit in the United States as well as
Thunder Bay, Sault Ste-Marie and Toronto in
Canada, take advantage of this direct maritime
link between our continent and foreign
destinations. It is the shortest waterway between
the world’s two most industrialized areas: Europe
and Central North-America.
The Saint-Lawrence begins in Lake Ontario and
ends in the Gulf of Saint-Lawrence. It is part of
the North-America’s main waterways and ranks
2nd in Canada and 3rd in North-America, after the
Mississippi River and the Mackenzie River. It
provides access to one of the world’s most
important economic markets.
In the summer season, commercial traffic,
including post-Panamax vessels, share the
waterway with a fleet of pleasure crafts and
commercial fishing vessels. In winter,
commercial shipping reaches the Port of Montreal
Le fleuve Saint-Laurent prend sa source au Lac
Ontario et termine son parcours dans le golfe du
Saint-Laurent. Le Saint-Laurent fait partie des
principales voies de navigation en Amérique du
Nord. Il se classe au 2e rang au Canada et au 3e
rang en Amérique du Nord, après le Mississippi et
le Mackenzie. Il donne accès à un marché
économique considéré comme l’un des plus
importants au monde.
Durant la belle saison, au trafic de navires
commerciaux pouvant atteindre les dimensions
post-Panamax s’ajoute toute une flottille de
plaisanciers et de navires de pêche commerciale.
Au cours de l’hiver, la navigation commerciale se
poursuit jusqu’à Montréal, situé à une distance de
plus de 900 km de l’estuaire. Montréal devient
donc un important point de transbordement des
navires vers les modes de transport terrestres.
Cette voie navigable se couvre normalement de
glace à partir de la fin du mois de décembre et
l’usage de brise-glaces et d’aéroglisseurs est
requis pendant plus de 3 mois afin de maintenir
un chenal sécuritaire ouvert à la circulation. En
plus de servir à maintenir le chenal libre de glace,
leurs services sont aussi requis pour escorter les
navires peu adaptés à des conditions rigoureuses
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 87 which is located 900 kilometres inland to the
southwest of the estuary and for this
reasonMontreal has become a major
transhipment port for products that are to be
delivered by other modes of transport.
This waterway is usually covered with ice
beginning at the end of December and the
use of icebreakers and air-cushion vehicles
(hovercrafts) are required for more than 3
months to keep the channel clear and safe for
marine traffic. In addition to keeping the
channel free of ice, icebreakers and
hovercrafts are also required to escort those
vessels that are less equipped to handle
severe conditions as well as to prevent floods
resulting from ice jams.
The Saint-Lawrence significantly narrows
close to Quebec City where it is less than 900
metres wide. It then widens up to TroisRivières, halfway between Quebec and
Montreal and from that point upstream widens
even more to form Lake St-Pierre, a 15-km
wide shallow water area studded with islands on
its westernmost tip. From there upstream, a 230metre wide dredged channel extends up to
Montreal. The first Saint-Lawrence Seaway Lock
where winter shipping ends is located just south
of Montreal.
Ice‐chocked ship in distress under the Quebec bridges Navire en détresse dans les glaces sous les ponts de Québec ainsi qu’à prévenir les inondations en cas
d’embâcle.
As if it were not difficult enough to navigate on the
river during the three other seasons, to the point
where pilotage is required over a distance of 400
kilometres, maintaining commercial navigation in
the winter brings a lot of additional challenges for
the Canadian Coast Guard to keep shipping
uninterrupted.
The Saint-Lawrence River presents specific
environmental conditions between Quebec City
and Montreal. For example, 6.0-metre tides at
Quebec City, 6-knot currents at some locations,
current switches direction with the tide, air
temperatures reaching -30oC in February and the
combined effect of winds, waves, ice and snow
continuously challenge the most experienced
mariners.
The Canadian Coast Guard undertakes
considerable efforts and expenditures to ensure
safe navigation in this waterway which is critical
La configuration du fleuve se rétrécit de manière
significative en face de la ville de Québec où il
passe à moins de 900 m de largeur. Il s’élargit
ensuite pour se prolonger jusqu’à Trois-Rivières,
à mi-chemin entre Québec et Montréal. De ce
point vers l'amont, il s’élargit pour devenir le Lac
St-Pierre, vaste étendue d’eau peu profonde de
15 km de largeur parsemée d’îles à son extrémité
ouest. En amont du Lac St-Pierre, un chenal
dragué de 230 m de largeur se prolonge jusqu’à
Montréal. C’est au sud de cette ville que se
trouve la première écluse se la Voie maritime du
St-Laurent, écluse qui représente la limite de la
navigation hivernale.
Déjà qu’il est difficile à naviguer sur le fleuve au
cours des trois autres saisons au point où du
pilotage y soit requis sur plus de 400 km, le
maintien de la navigation commerciale en hiver
apporte des défis additionnels pour la Garde
côtière canadienne, responsable d’y assurer la
navigation ininterrompue.
Le fleuve présente des conditions
environnementales toutes particulières entre les
villes de Québec et de Montréal. Il faut
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 88 Icebreakers tasked to break an ice jam west of Quebec bridges Travail des brise‐glaces pour déloger un embâcle à l’ouest des ponts de Québec for the Canadian economy. It’s worth mentioning
of the presence at certain locations of installations
designed to facilitate river flow and ice control.
Artificial islands and ice booms are installed on
Lake St-Pierre to keep ice on its shores and
stabilize the ice cover outside the channel.
Upstream from Lake St-Pierre, several weirs were
designed connecting the islands together as a
means of increasing water level in the Port of
Montreal.
For many years, air patrols, surveillance cameras,
radars and other special instruments have been
installed to assist with monitoring ice behaviour
on critical segments of the river and helps
specialists determine the most appropriate
moment to intervene in case of ice jams in order
to ensure safe navigation and prevent the risk of
floods.
notamment mentionner les marées qui atteignent
plus de 6,0 m à Québec ainsi que des courants
de 6 nœuds à certains endroits. De plus, des
marées qui font alterner la direction du courant
deux fois par jour, les températures pouvant
atteindre les -30oC en février et l’effet combiné
des vents, des vagues, de la glace et de la neige
sont des contraintes qui défient constamment la
navigation.
La Garde côtière canadienne déploie de multiples
efforts et dépense des sommes importantes pour
assurer la sécurité de la navigation dans ce
secteur essentiel à l’économie du Canada. Il faut
notamment mentionner la présence en différents
endroits, d’installations conçues afin de faciliter le
débit du fleuve et le contrôle des glaces. Le lac
St-Pierre comporte ainsi des îlots artificiels et des
estacades pour retenir les glaces sur ses rives et
stabiliser le couvert de glaces hors du chenal. En
amont du lac St-Pierre, le fleuve comporte
plusieurs réversoirs reliant les îles et qui sont
conçus de manière à rehausser le niveau d’eau
au port de Montréal.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 89 2.9-metre Summer Buoy
CURRENT AIDS TO NAVIGATION SYSTEM
The current AtoN system stretches over the 250
kilometres that separate Quebec City and
Montreal. It is composed of fixed, floating and
electronic aids. This segment of the river,
sometimes very narrow, is comprised of at least
29 curves of more than 20 degrees.
The fixed aid network includes 172 navigation
lights, more than 141 range lights, 17 Racons and
radar reflectors, all supported by a dual-coverage
DGPS system.
Because of winter navigation requirements, the
floating aid network is presently composed of
363 lighted summer buoys that must be
withdrawn in the fall and replaced for the winter
with 167 unlighted spar buoys. In the spring the
cycle begins again as 167 unlighted spar buoys
are replaced with
Depuis plusieurs années, des patrouilles
aériennes, des caméras de surveillance, des
radars et d’autres instruments spécialisés
contribuent à la surveillance du comportement
des glaces dans les secteurs critiques. Ils aident
les spécialistes à déterminer le meilleur moment
pour intervenir en cas d’embâcle afin de maintenir
une navigation sécuritaire et prévenir tout risque
d’inondation.
SYSTÈME ACTUEL D’AIDES À LA
NAVIGATION
Le système d’aides à la navigation actuel s’étend
sur les 250 km séparant la ville de Québec de la
ville de Montréal. Il est constitué d’aides fixes,
flottantes et électroniques. Ce tronçon parfois
très étroit ne comporte pas moins de 29 courbes
de plus de 20 degrés.
Le réseau d’aides fixes comporte 172 feux de
navigation, plus de 141 alignements, 17 Racons
et réflecteurs radar, le tout supporté par un
système DGPS à double couverture.
En raison des exigences de la navigation
hivernale, le réseau d’aides flottantes se
compose présentement de 363 bouées d’été
lumineuses qui doivent être retirées de l'eau à
chaque automne et remplacées par 167 bouées
espar non lumineuses pour la période hivernale.
Au printemps, l’opération inverse doit être
exécutée afin de remettre en place les
363 bouées lumineuses.
2.9‐metre Summer Buoy Bouée d’été de 2,9 m L’opération de remplacement des bouées d’été
par les bouées d’hiver doit se faire sur une
période très restreinte en raison des impacts sur
la navigation et, par conséquent, des impacts
économiques pour les armateurs. En effet, le
maintien des bouées lumineuses est une
exigence à la navigation nocturne des navires
commerciaux dans ce secteur. À partir du
moment où les bouées lumineuses sont retirées
pour faire place aux bouées d’hiver non
lumineuses, la majorité des armateurs cessent de
naviguer de nuit, allongeant ainsi la durée de
transit vers leur destination.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 90 363 lighted buoys.
The replacement of summer buoys with winter
buoys must take place over a very limited period
of time because of potential impacts on shipping
and, consequently, economic impacts on
shipowners. Maintained lighted buoys are a night
navigation requirement for commercial shipping in
this sector of the seaway. From the time lighted
buoys are withdrawn and replaced with unlighted
winter buoys, most shipowners will stop night
navigation and, as a result, increasing their transit
time to destination.
0.7‐metre Winter Spar Buoy Bouée espar d’hiver de 0,7 m De plus, le fait de ne plus offrir de service d’aides
à la navigation lumineuses entraîne le besoin de
doubler le nombre de pilotes embarqués de la
Corporation de pilotage du St-Laurent,
augmentant significativement les coûts assumés
par les armateurs.
Afin de réduire le plus possible les impacts
négatifs, l’enlèvement des bouées d’été doit se
faire le plus tard possible dans la saison sans
quoi les bouées d’été se chargent de glace, se
renversent ou coulent, devenant ainsi un risque
pour la navigation. C’est sans considérer les
dommages aux équipements qui en résultent et
leur récupération par la Garde côtière. Il faut
noter que le gel de la surface de l’eau se produit
souvent d’une manière très rapide lors du
passage d’une vague de froid ou lors de chutesde
neige importantes. Il faut aussi noter que la
récupération de bouées givrées représente un
risque élevé pour le personnel naviguant qui doit
travailler rapidement dans des conditions difficiles,
souvent sur un pont recouvert de glace suite aux
Also, stopping lighted Aids to Navigation services
means doubling the number of St-Lawrence Pilot
Corporation pilots thus significantly increasing the
cost for shipowners.
In order to minimize adverse impacts as much as
possible, summer buoy removal must be delayed
as late as possible in the season, otherwise
summer buoys will ice up, tip over or sink
becoming hazards to navigation. Resulting
damage to and retrieval of equipment by the
Coast Guard must also be considered. It should
be noted that water will often freeze quickly on
the surface with a passing cold air mass or
significant snowfalls. Retrieving ice-covered
buoys represents a high risks for sea-going
personnel who must work quickly under difficult
conditions, often on a bridge that is covered with
ice during the operations.
In addition to being more risky, these operations
cause tremendous pressure on the Canadian
Coast Guard resources which requires the
tasking of several vessels and hovercrafts to the
same area while maintaining Search & Rescue
coverage over adjacent areas. It is worth
mentioning that the Canadian Coast Guard
operates multitask vessels and hovercrafts but
has no vessel dedicated solely to buoy tending.
Ice‐covered Summer Buoy Retrieval Récupération d’une bouée d’été recouverte de glace manœuvres de récupération.
En plus d’être plus risquées, ces opérations
exercent une pression énorme sur les ressources
de la Garde côtière qui doit concentrer plusieurs
navires et aéroglisseurs dans le même secteur
tout en s’assurant de maintenir la couverture en
matière de Recherche et de Sauvetage dans les
secteurs adjacents. Il faut noter que la Garde
côtière canadienne opère des navires et
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 91 In the spring, shipowners expect that lighted
buoys will be positioned as soon as ice
disappears to be able to resume normal 24-hour
operations with only one pilot aboard. Any delay
in installing summer buoys has a direct impact on
their operating costs.
The use of 4-season buoys would enable the
CCG to concentrate its buoy tending and
maintenance effort at times of the year when
CCG Fleet services are less in demand and
environmental conditions are more favourable.
This project is presented in response to this
recommendation to provide, for as long a period
as it is possible, a lighted floating aids service that
would not require withdrawing or installing buoys
at critical times of the year.
PROJECT PRESENTATION
Ce projet est le fruit de plusieurs années de
recherche, de travail et d’essais sur place. Il est
le fruit de la collaboration de plusieurs ingénieurs
civils ainsi que d’ingénieurs et de techniciens
spécialisés dans les domaines de l’hydraulique,
du comportement des glaces, des structures, de
la navigation fluviale ainsi que de l’architecture
navale. Ce projet a exigé le travail concerté de
centres de recherche publics, de partenaires du
secteur privé et du personnel de la Garde
canadienne de différentes régions du pays.
Project objectives were defined through
consultations with shipowners of the SaintLawrence and a number of CCG personnel both
sea-going and technical services staff.
Objective: Develop a 4-season buoy for the SaintLawrence River that:
Can be kept in service for two years without
any maintenance;
•
Can be maintained during off-peak periods
only;
•
Can provide visual and radar service, day and
night (lighted), nine months of the year.
L’utilisation d’une bouée 4-saisons permettrait de
concentrer les efforts de balisage et d’entretien à
des périodes de l’année où les services de la
flotte de la Garde côtière sont moins sollicités et à
des périodes où les conditions climatiques sont
plus clémentes. Le projet présenté fait donc suite
à cette recommandation d’offrir un service de
balisage flottant lumineux le plus longtemps
possible et n’exigeant pas le retrait ou la pose
des bouées en périodes critiques.
PRÉSENTATION DU PROJET
This project is the result of many years of
collaborative research and work as well as in-situ
site testing by multidisciplinary partners who have
strived to develop a unique product. The team
consists of civil and hydraulic engineers,
technicians specializing in hydraulics, ice
behaviour, structures, seaway navigation and
naval architects. Public research centres, private
sector partners and Canadian Coast Guard staff
from different regions of the Country were called
upon to work on this project.
•
Au printemps, les armateurs s’attendent
évidemment que les bouées lumineuses soient
remises en fonction dès la disparition des glaces
afin de pouvoir reprendre leurs opérations
régulières en naviguant 24 heures par jour sans
la présence du second pilote. Évidemment, tout
retard dans le déploiement des bouées d’été a
une incidence directe sur leurs coûts d’opération.
Les objectifs ont été définis suite à la consultation
des armateurs naviguant sur le St-Laurent ainsi
que de plusieurs membres du personnel de la
Garde côtière, autant du personnel naviguant que
des services techniques.
L’objectif du projet est le suivant : Développer une
bouée 4-saisons pour le fleuve Saint-Laurent qui :
The last bullet of the project objective is in
response to one of the project development
findings that it is technically impossible to
guarantee a lighted or radar service during the 3
most critical months of the year, January to March,
•
peut être maintenue à l'eau pendant deux ans
sans nécessiter d’entretien;
•
peut être entretenue uniquement hors des
périodes de pointe;
•
offre un service visuel et radar, de jour et de
nuit (lumineux), neuf mois par année.
Le dernier énoncé de l’objectif du projet fait
référence au fait qu’il a été considéré, lors du
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 92 due to ice accretion on the lantern and ice
pressure. Winter buoys have the particularity of
reacting to ice pressure by tipping over and laying
under the ice until it disappears; winter spars may
also disappear completely for short/long periods
of times thus reducing the level of service (LOS),
sometimes non-existant.
The methodology used to develop this project is
as follows. The first phase of the project consisted
of an exhaustive literature survey to determine
what existed in terms of knowledge but also in
terms of applications under similar conditions.
This research was unsuccessful in finding
locations where commercial traffic was
maintained under such severe weather and
environmental conditions. Therefore, the
conclusion was reached that no buoy was
currently available that could meet our specific
requirements.
Another finding of this study is that we were
lacking knowledge on the characterization of the
hydrodynamic and environmental setting in which
these buoys would need to perform and survive.
Therefore, after some additional research was
done, the Quebec-Montreal segment was
characterized under 4 different sectors presenting
fairly different characteristics, which can be seen
in the table below.
développement du projet, qu’il est techniquement
impossible de garantir un service lumineux ou
radar pendant les 3 mois les plus critiques de
l’année, soit de janvier à mars en raison de la
formation de glace sur la lanterne et de la
poussée de la glace. Les bouées d’hiver ayant
pour particularité de réagir à la pression des
glaces en s’inclinant et en se couchant sous la
couche de glace jusqu’à ce que celle-ci soit
disparue, il peut arriver que la bouée disparaisse
complètement pour des périodes plus ou moins
longues, offrant ainsi un service diminué ou
parfois même, temporairement inexistant.
La méthodologie utilisée pour mener à bien ce
projet a été la suivante. La première phase du
projet a consisté en une recherche
bibliographique exhaustive afin de déterminer ce
qui existait en termes de connaissances mais
aussi d’applications dans des conditions
similaires. Cette recherche n’a pas permis de
trouver d’endroits où la navigation commerciale
était maintenue dans des conditions climatiques
et environnementales aussi sévères. De ce fait, la
conclusion était qu’aucune bouée pouvant
répondre à notre besoin spécifique n’existait
actuellement.
Une autre conclusion tirée de cette étude est que
des connaissances nous manquaient quant à la
.
Sector Secteur Depth – Profondeur (m) Current speed (knots) Vitesse du courant (noeuds) Tide presence Présence de marée (maximum) Maximum wind speed Vitesse du vent maximum (km/h) Maximum wave height Hauteur de vagues maximum*(m) S1 S2 S3 8 – 12 7 – 12 8 ‐18 0.1 – 1.5 0.1 – 0.5 0.1 – 3.5 60 60 60 1.2 N/A – N/D 1.2 S4 8 ‐ 33 0.0 – 6.0 No ‐ Non No ‐ Non Downstream part only Partie aval seulement (0.5 m) Yes – Oui (6.0 m) Maximum ice thickness Epaisseur de glace maximum (cm) N/A – N/D N/A – N/D 75 70 2 100 Table 4 – Quebec‐Montreal Segment Sector Characteristics Tableau 1 – Caractéristiques des secteurs du tronçon Québec‐ Montréal PERFORMANCE REQUIREMENTS
From the project statement and knowledge
acquired during the first two stages, we were able
to identify what operational performance
caractérisation du milieu hydrodynamique et
environnemental dans lequel ces bouées
devraient performer et survivre. Ainsi, suite à des
recherches additionnelles, le tronçon Québec –
Montréal, a été caractérisé en 4 différents
secteurs présentant des caractéristiques
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 93 standards our buoys should meet. Below is a list
of the operational criteria for the 9 month period
during which the buoy must remain operational.
For the remaining 3 months, the buoy must
withstand a hostile environment without damage
and fully resume its functions once ice has
disappeared.
•
Visual range: 3 NM
•
Luminous range: 3 NM
•
Radar range: more than 2 NM
•
Air draft: more than 2.0 m
•
Verticality: tilt below 6 degrees
The following technical performance standards
were retained:
•
Structure: limited steel-yield deformation
•
Colour: retention of at least 75 % of the
surface paint and colour after 2 years in
service
•
•
•
•
Lantern: uninterrupted operation even after
the lantern has been submerged deeper than
1 metre for long periods of time at
temperatures of 4o C
Battery: maintenance-free primary battery for
at least 2 years
Electrical system: maintenance-free operation
for at least 2 years
Signage: visible reflective marking for at least
2 years.
Then a search for solutions began in order to
determine which buoy could perform the required
functions in sectors S3 and S4. This included
finding whether or not some Commercial- off-theshelf (COTS) buoys existed that could meet our
requirements and, to that end, the focus was put
on buoy manufacturers. This research could not
identify any manufacturers capable of supplying
a buoy meeting our requirements. In parallel,
attempts to modify existing spar buoys were
made without success. As a result, our efforts
were focused on designing a buoy specially
adapted to withstand these severe environmental
conditions and meet our performance
requirements.
passablement différentes. Le tableau 1 montre
les différences entre chacun des secteurs.
EXIGENCES DE PERFORMANCE
À partir de l’énoncé de projet et des
connaissances acquises au cours des 2 étapes
précédentes, les normes de performance
opérationnelles que nos bouées devraient
rencontrer ont été précisées. Voici donc les
critères opérationnels retenus pour la période de
9 mois où laquelle la bouée doit demeurer
entièrement opérationnelle. Pour les 3 mois
subséquents, la bouée doit survivre dans son
environnement hostile sans être endommagée et
reprendre intégralement ses fonctions une fois la
glace disparue.
•
Portée visuelle de 3 NM
•
Portée lumineuse de 3 NM
•
Portée radar supérieure à 2 NM
•
Tirant d’air supérieur à 2.0 m
•
Verticalité : inclinaison inférieure à 6 degrés
Les normes de performance techniques qui ont
été retenues sont les suivantes :
•
Structure : Déformations limitées dans le
domaine élastique de l’acier.
•
Couleur : Rétention d’au moins 75 % de la
surface de la peinture et reconnaissance de la
couleur après 2 ans en service.
•
Lanterne : Fonctionnement ininterrompu
même si la lanterne est submergée pendant
de longues périodes à une profondeur de plus
d’un mètre à des températures de l’ordre de
4o C.
•
Batterie : Aucun entretien de la batterie
primaire avant au moins 2 ans.
•
Système électrique : Fonctionnement sans
entretien pendant au moins deux ans.
•
Lettrage : Marquage réfléchissant lisible pour
au moins 2 ans.
La recherche de solution a ensuite commencé
pour déterminer quelle bouée pourrait remplir ses
fonctions adéquatement dans les secteurs S3 et
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 94 DEVELOPMENT OF THE 4-SEASON BUOY
Sectors S1 and S2 are areas that are not affected
by tides and where conditions are less severe
with currents not exceeding 1.5 knots. As a result,
some buoys from our current inventory were
modified to perform adequately under such
conditions.
For sectors S3 and S4 however, CCG did not
have a buoy that could withstand prevailing
conditions and meet expected performance
requirements. Because of the differences
between sectors S3 and S4, more specifically in
terms of water depth and current speed, it was
determined that two versions of buoys would be
required. Therefore, the model developed for
Sector S3 is 9.2 metres in length as opposed to
10.0 metres for Sector S4.
The lower section of the 9.2-metre buoy consists
of a watertight compartment made of a 5.4-metre
long X 600-mm diameter steel cylinder. The
upper section is 1.3 metres in diameter which
represents approximately 55 % of the buoy’s
overall length. Steel thickness for CSA G40.21
300W is 9.5 mm reinforced with interior frames
(ribs) relatively close to one another. That section
has three (3) additional watertight compartments
to ensure buoyancy in case of structural damage.
A steel counterweight of more than 1000 kg is
placed at the bottom of the lower section to
ensure vertical stability of the buoy.
The buoy’s mooring system is made of the same
components used for summer buoys, i.e., a 3.6metric tonne mooring anchor with 28 mm Grade 2
mooring chains attached to the buoy with a bridle.
The lantern is secured on top of the battery
compartment lid. The lantern selected for this
buoy is the Sabik MPV3 model. This heavy duty
lantern designed for demanding situations has
been used by the Coast Guard for a number of
years. However, it has never been used in
Canada under conditions as severe as those
existing in these sectors. Faultless operation and
survival will be key factors to project success.
In this concept, the battery can be inserted from
the top of the buoy which facilitates maintenance
as the buoy will not have to be pulled out of the
water for servicing. The battery is an integral part
S4. Il fallait déterminer s’il existait sur le marché
un ou plusieurs modèles de bouées qui
pourraient rendre le service tel qu’on le désirait et
pour ce faire, notre recherche s’est tournée
initialement vers les manufacturiers de bouées.
Mais auparavant, des tentatives ont été
effectuées en modifiant les bouées espar actuelle,
mais sans grand succès.
La conclusion de ces recherches a été qu’aucun
manufacturier ne pouvait fournir une bouée
rencontrant ces exigences. La conception d’une
bouée spécialement adaptée à ces conditions
rigoureuses et à nos exigences de performance a
donc débuté.
DÉVELOPPEMENT DE LA BOUÉE 4-SAISONS
Les secteurs identifiés S1 et S2 sont des zones
qui ne sont pas affectées par les marées où les
conditions sont moins sévères avec des courants
n’excédant pas les 1,5 nœuds. De ce fait,
certaines bouées de notre parc de bouées actuel
ont pu être modifiées pour performer
adéquatement dans de telles conditions.
Toutefois, pour les secteurs S3 et S4, la Garde
côtière ne possédait aucune bouée pouvant
résister aux conditions prévalentes et répondre
aux exigences de performance attendues. En
raison des différences entre les secteurs S3 et S4,
notamment en ce qui concerne la profondeur
d’eau et la vitesse du courant, il a été déterminé
que deux versions de la bouée seraient
nécessaires. Ainsi, le modèle développé pour le
secteur S3 fait une longueur totale de 9,2 m alors
que celui qui sera utilisé dans le secteur S4 fera
10,0 m.
Pour la bouée de 9.2 m, la section inférieure est
faite d’un cylindre d’acier de 5,4 m de longueur et
de 600 mm de diamètre formant un compartiment
étanche. La section supérieure fait 1,3 m de
diamètre et représente environ 55 % de la
longueur totale de la bouée. L’épaisseur de
l’acier de type CSA G40.21 300W est de 9,5 mm
renforcée par des membrures intérieures
relativement rapprochées. Cette section comporte
trois (3) compartiments étanches additionnels
pour assurer une flottabilité en cas de dommages
structuraux. Un contrepoids en acier de plus de
1000 kg est situé au bas de la section inférieure
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 95 La lanterne est fixée sur le dessus du couvercle
du compartiment de la batterie. Le choix de la
lanterne qui sera utilisée sur ce modèle de bouée
s’est arrêté sur la Sabik MPV3. Cette robuste
lanterne conçue pour des situations exigeantes
est utilisée par la Garde côtière canadienne
depuis plusieurs années déjà. Toutefois, son
usage dans des conditions aussi rigoureuses est
une première au Canada. Son fonctionnement
impeccable et sa survie sont essentiels à la
réussite de ce projet.
of the hull, slightly above the water line. The
battery can be easily inserted and secured by
means of a built-in guiding rail. It is estimated that
a single battery will power the light over a period
of 2 years. The primary battery retained for the
prototypes is an 850 Ah alkaline battery
manufactured by Celltech Ab of Sweden.
TRIALS
Two prototypes of the short version of the buoy
were built and deployed for two (2) full years.
Initial deployment in ice-free waters indicated
exceptional vertical stability. However, a rotating
movement around its longitudinal axis was
deemed too much and adjustments had to be
made to the mooring points.
In order to monitor their performance under all
potential conditions, these buoys were deployed
near ice surveillance sites where cameras
recorded their behaviour over long periods of time
both during high water stages and calm periods of
the summer. Their performances were also
observed in average spring and fall ice conditions
as well as in more severe winter conditions.
The long buoy prototype should be fabricated
during the coming year and trialed afterwards.
Fabrication was delayed due to financial
constraints but all drawings are now completed
and it is only a question of time before production
gets underway.
RESULTS
Buoy
Conclusions drawn from tests conducted in the
winter of 2007 and 2008 show that, in the sectors
where conditions are less severe (currents below
1.5 knots), it is conceivable to use plastic buoys
supporting a radar reflector and that steel is not
critical to the buoy structure. Because these
buoys have been used by the Coast Guard for a
number of years at lakeside locations or on low
flow rivers, they could be adapted to critical river
flows after a detailed analysis of their
hydrodynamic behaviour. Some adjustments had
to be made to their mooring mechanisms to keep
the buoys more stable and vertical.
Le concept prévoit aussi que la batterie puisse
s’insérer par le dessus de la bouée, facilitant de
ce fait l’entretien puisque la bouée n’aura pas à
être retirée de l’eau pour effectuer le service. La
batterie se situe à même le corps de la bouée,
légèrement au dessus de la ligne de flottaison.
Un guide permet son insertion facile tout en la
maintenant bien en place. Il est estimé qu’une
seule batterie sera suffisante pour assurer un
fonctionnement du feu pour une période de 2 ans.
La batterie primaire qui a été retenue pour l’usage
dans les prototypes est une pile alcaline de
850 Ah produite par la compagnie Celltech Ab de
Suède.
ESSAIS
Deux prototypes de la version courte de la bouée
ont été fabriqués et déployés durant deux
(2) années complètes. Le déploiement initial en
eau libre de glace a démontré une stabilité
exceptionnelle de la bouée en position verticale.
Toutefois, un mouvement de rotation autour de
son axe longitudinal a été jugé trop important et
des ajustements ont été apportés aux points
d’amarrage.
Afin de suivre leur rendement dans les toutes les
conditions possibles, ces bouées ont été
déployées à proximité de sites de surveillance
des glaces où des caméras ont été pointées vers
elles pendant de longues périodes. On a ainsi pu
observer leur comportement sous diverses
conditions, autant en période de crue que lors
des périodes plus calmes de la fin de l’été. Leur
performance a aussi été observée sous les
conditions moyennes de glace du printemps et de
l’automne ainsi que lors des conditions plus
sévères en hiver.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 96 Le prototype du modèle long de la bouée devrait
être produit au cours de la prochaine année et
mis à l’essai par la suite. Diverses contraintes,
notamment la question financière, a retardé sa
fabrication. Toutefois, tout n’est qu’une question
de temps, les plans étant entièrement complétés
et la fabrication prête à démarrer.
In currents between 1.5 and 5.0 knots, the new
1.3-metre buoy showed good resistance to ice
impact and abrasion. In terms of its structure, this
buoy withstood impacts and maintained its
circular shape despite 26G accelerations when
impacted by ice masses of many kilometres long
and thickness ranging from 0.7 and 1.0 m.
These buoys offer good radar reflectivity and
sufficient visual range for the nine months they
must stay fully operational. Comments from
mariners and pilots confirm the visual and radar
performance of this model. Not only are these
adequate but reports indicate that the buoys are
well appreciated in-season by commercial users
and boaters.
RÉSULTATS
Bouée
Les conclusions tirées des essais des hivers
2007 et 2008 montrent que dans les secteurs où
les conditions sont les moins rigoureuses
(courants inférieur à 1.5 noeuds), il est
envisageable d’utiliser des bouées faites de
matière plastique dans laquelle se trouve un
réflecteur radar et que l’usage de l'acier n’est pas
essentiel à la structure de la bouée. Ces bouées
étant en usage depuis plusieurs années à la
Garde côtière dans des sites lacustres ou en
rivières à faible débit ont pu être adaptées au
régime fluvial suite à une étude détaillée de leur
comportement hydrodynamique. Certains
ajustements ont dû être apportés au dispositif
d’amarrage de manière à rendre ces bouées
stables et verticales.
Light
This low-profile lantern designed specifically for
use under difficult conditions performed well
during the trial period.
However, some
modifications had to be
made because of the
behaviour of the buoys on
which these will be installed,
i.e. the tilt switch had to be
removed so the light could
stay ON when the buoy was tilted by ice
movement.
Paint
After several tests, a paint system was achieved
for the prototype steel buoys, i.e., Inerta 160 paint,
well known for ship hull coating.
Because the buoy needs to maintain its colour for
2 years, a maximum paint colour loss of 25% was
set. It was determined that a buoy which
maintains its colour on 75 % of its surface is still
identifiable; needless to say, the shape of the
buoy also helps identification.
Reflective Signage
One of the project requirements is keeping each
buoy recognizable. Signage is essential to
boaters during summer months. The new buoy
signage had to provide the same characteristics
as provided on current summer buoys, i.e., reflect
light received from a light source. Epoxy paint
Pour les endroits subissant un courant entre
1.5 et 5.0 nœuds, la nouvelle bouée de 1,3 m a
bien résisté aux impacts et à l’abrasion de la
glace. Structuralement parlant, cette bouée
résiste beaucoup mieux aux chocs et garde bien
sa forme circulaire malgré les accélérations de
l’ordre de 26 G au moment des impacts avec des
masses de glaces pouvant avoir plusieurs
kilomètres de long et une épaisseur variant entre
0,7 et 1,0 m.
Ces bouées offrent une bonne réflectivité radar et
une portée visuelle suffisante pendant les neuf
mois où elles doivent demeurer pleinement
opérationnelles. Les commentaires des
navigateurs et pilotes confirment la performance
visuelle et radar de ce modèle de bouée. Non
seulement sont-elles adéquates, mais on nous
rapporte qu’elles sont aussi bien appréciées des
utilisateurs commerciaux et des plaisanciers
naviguant sur le fleuve au cours de la belle saison.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 97 dusted with glass microbeads (similar to road
marking) was used.
Feu
Cette lanterne surbaissée conçue spécialement
pour les conditions difficile, a bien performé au
cours des tests.
This technique was rejected after lab tests for not
meeting minimum requirements in terms of
reflection rate. Other tests are underway to
resolve this issue.
Battery
In light of the tests performed over the last years,
it was determined that although the buoy can
adequately withstand
ice impact, such is not
the case for the battery.
Two batteries retrieved
after
testing
were
opened to see how the
inside withstood these
tests. It was found that
the battery cells had
shifted with impacts
and vibrations and a
breakdown could have
occurred any minute.
OTHER CHALLENGES
The lantern used withstood testing despite a few
traces of humidity and water ingress of unknown
origin. Further testing will help determine if such
water ingress was accidental, for example during
installation, or if the conditions under which the
lantern must operate exceed its actual capacity.
Since the manufacturer has recently announced
some upcoming changes to the lantern, this new
model will be used for future tests.
Although the battery used for the trial program
kept working during the tests, its internal condition
raised doubts as to its resistance to vibrations
and ice impact. Research is currently underway to
develop a battery that will better withstand
impacts and vibrations generated by the
environment in which it needs to operate. Ten
new batteries are ready to be tested in
laboratories to check their resistance to vibration
and ice impacts before being deployed in the field.
As mentioned earlier, the buoy signage did not
meet specified performance criteria and other
tests will be carried out over the coming months
Toutefois, certaines modifications ont dû y être
apportées en raison du comportement des
bouées sur lesquelles elles seront installées.
Ainsi, on a enlevé l’interrupteur d’inclinaison,
permettant ainsi à la lanterne de rester allumée
même si la bouée s’inclinait dû à la poussée des
glaces.
Peinture
Après plusieurs essais, un système de peinture a
été retenu pour recouvrir les bouées d’acier de
notre essai. La peinture Inerta 160,
avantageusement connue pour son usage
comme revêtement de coques de navires, a été
utilisée.
Comme la bouée doit retenir sa couleur pour une
durée de 2 ans, une limite une perte de peinture
maximale de 25% a été fixée. Il a été évalué
qu’une bouée qui retient sa couleur sur 75 % de
sa superficie demeure reconnaissable. Il va
aussi de soi que la forme de la bouée contribue à
la reconnaissance de la bouée en plus de sa
couleur.
Marquage réfléchissant
Une des exigences du projet est le maintien d’une
identification de chaque bouée. L’usage de ce
marquage est essentiel pour nos plaisanciers qui
naviguent au cours de l’été. Cette marque devra
conserver les mêmes caractéristiques que celles
actuellement utilisées sur les bouées d’été, soit
de réfléchir la lumière lorsqu’on la pointe avec
une source lumineuse. Pour le marquage, une
peinture à base d’époxy sur laquelle a été
saupoudrée des microbilles de verre (tel qu’utilisé
pour le marquage routier) a été utilisée.
Après les essais en laboratoire, cette technique a
été rejetée parce qu’elle ne rencontrait pas les
exigences minimales en terme de taux de
réflexion. D’autres essais sont en cours pour
pallier à cette difficulté.
Batterie
À la lumière des essais des dernières années, il a
été constaté que, même si la bouée est en
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 98 and years using other types of reflective material.
CONCLUSION
CCG’s plan for the time being is to produce and deploy a certain quantity of these buoys at different
locations for larger scale trials. Then, mass production may be started to proceed with the replacement of
the actual Saint-Lawrence Buoy Network.
CCG has high hopes for this type of buoy that may significantly reduce buoyage costs in that area of the
Country through partial elimination of the requirement to deploy two floating aids systems. This buoy may
actually replace current buoys and alleviate the stress imposed on fleet operations during fall and spring
peak periods.
It is conceivable that this new buoy model will eventually be used elsewhere in Canada, in places subjected
to strong currents and ice jams at river junctions at various locations on the East Coast. It is also
conceivable that these buoys will be best utilize in locations where buoys are often hit by tugs and barges
carrying wood or other consumer products.
Lors de la récupération de deux piles à la fin des tests, leur enveloppe extérieure a été ouverte pour voir
comment le tout s’était comporté à l’intérieur. Il a été constaté que les cellules à l’intérieur des batteries
s’étaient déplacées en raison des chocs et des vibrations, risquant la panne à tout moment.
DÉFIS RÉSIDUELS
La lanterne utilisée s’est montrée à la hauteur malgré quelques traces d’humidité et d’infiltrations d’eau
d’origine inconnue. D’autres essais permettront de déterminer si cette infiltration est d’origine accidentelle,
par exemple lors du montage de la lanterne ou si, par contre, les conditions dans lesquelles elle doit opérer
excèdent ses capacités réelles. Comme le manufacturier a récemment annoncé des changements à sa
lanterne, ce nouveau modèle sera utilisé lors des prochains essais.
Quoique la batterie qui a été utilisée dans le programme d’essai n’ait pas fait défaut durant le test, sa
condition interne a soulevé des doutes quant à sa résistance aux vibrations et aux impacts de la glace.
Une recherche est actuellement en cours pour développer une batterie plus résistante aux impacts et aux
vibrations générées par le milieu dans lequel elles doivent opérer. Une dizaine de ces nouvelles piles sont
prêtes à être testées en laboratoire pour vérifier leur résistance aux impacts et à la vibration avant leur
déploiement opérationnel.
Tel que mentionné plus haut, le marquage d’identification de la bouée n’a pas rencontré les critères de
performance spécifiés. D’autres essais seront effectués au cours des mois et années à venir avec d’autres
types de matériaux réfléchissants.
CONCLUSION
Le plan actuel de la Garde côtière canadienne est de produire un certain nombre de ces bouées et de les
déployer à différents endroits pour en faire l’essai à plus grande échelle. Par la suite, une production
massive pourra être démarrée afin de procéder au remplacement du réseau actuel de bouées du SaintLaurent.
La Garde côtière canadienne fonde de grands espoirs sur ce type de bouée qui pourrait réduire de manière
significative le coût de son balisage dans ce secteur du pays en éliminant partiellement le besoin de
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 99 recourir à deux systèmes de balisage flottant. Cette bouée pourrait remplacer les bouées actuelles et ainsi
réduire le stress imposé à ses opérations de navires durant les périodes de pointe de l’automne et du
printemps.
Il est aussi possible de croire que ce nouveau modèle de bouée pourra éventuellement être utilisé à
plusieurs autres endroits au Canada, notamment dans les endroits soumis à de forts courants et à l’impact
des glaces à l’embouchures des rivières à différents endroits sur la côte est du pays. Il est aussi possible
de croire que ces bouées pourraient être avantageusement utilisées dans des endroits où les bouées sont
souvent heurtées par des barges tirées par des remorqueurs et convoyant du bois ainsi que divers produits
de consommation.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 100 The Recapitalisation of the GLA’s Marine Differential GPS Network A Grant & N. Ward, The General Lighthouse Authorities of the United Kingdom and Ireland, UK, A Cran, The Northern Lighthouse Board, UK, R Tomkins, Trinity House, UK and S Doyle, The Commissioners of Irish Lights, Ireland BIOGRAPHY
Dr. Alan Grant is a Principal Engineer for the Research and Radionavigation directorate of the General
Lighthouse Authorities of the UK and Ireland. He is project manager and technical lead for all GNSS projects
within the directorate. He received the degrees of B.Sc. and Ph.D. from Staffordshire University and the
University of Wales respectively. He is an Associate Fellow of the Royal Institute of Navigation, a member of
the US Institute of Navigation, and is a Chartered Physicist
Mr Alan Cran is an Electrical Engineer at the Northern Lighthouse Board. He has an Honours Degree in
Engineering from Aberdeen University and has been a Chartered Engineer for 17 years. He has previously
worked in the areas of instrumentation, control and automation in the Defence, Oil and Water industries.
Mr Richard Tomkins is Principal Electrical Engineer for Trinity House. As such he is responsible
development and implementation of policies and standards to ensure the safe, reliable, efficient and cost
effective delivery of all electrical aspects of Trinity Houses assets. A member of, and business partner
representative of the Institution of Engineering and Technology.
Dr. Nick Ward is Research Director of the General Lighthouse Authorities of the UK and Ireland, with
responsibility for strategy & systems studies in radio-navigation and communications. He was closely involved
in the international development and standardisation of the DGPS service and is currently vice chairman of
the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA) e-Navigation
committee. He is a Chartered Engineer and a Fellow of the Royal Institute of Navigation.
Mr. Seamus Doyle is Head of Engineering for the Commissioners of Irish Lights with responsibility for
delivery of engineering strategy, planning, investment, design and maintenance of all Irish Lights aids to
navigation. He is currently vice chairman of the International Association of Marine Aids to Navigation and
Lighthouse Authorities (IALA) Engineering, Environment and Preservation of Historic Lighthouses Committee
and a member of the IALA Policy Advisory Panel. He is a Chartered Engineer, a Fellow of the Institution of
Engineering and Technology, and a Fellow of the Royal Institute of Navigation. He is System Director for the
DGPS of the General Lighthouse Authorities (GLA) of UK and Ireland.
ABSTRACT
The mission of the General Lighthouse Authorities of the United Kingdom and Ireland (GLAs) is to deliver a
reliable, efficient and cost-effective Aids-to-Navigation (AtoN) service for the benefit and safety of all
mariners.
The GLAs’ provide a maritime differential GPS (DGPS) service, which was installed nearly a decade ago.
While it was state of the art at the time, it is now nearing the end of its operational life and in need of
replacement. The present system may not meet all the requirements set out in IMO Resolution A.915(22)
for Future GNSS and may not meet the needs of emerging applications with the further development in the
various GNSS constellations.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 101 This paper describes this recapitalisation project, including information on the project cycle; a description of
the user requirements; available options and the selected system design along with the progress to date on
this important marine Aid-to-Navigation project.
RÉSUMÉ
La mission du Groupement général des phares du Royaume-Uni et d’Irlande (GLAs) est d’offrir un service
d’aides à la navigation fiable, efficace et rentable pour le bénéfice et la sécurité de tous les marins.
Les GLAs fournissent un service de GPD différentiel (DGPS), qui a été installé il y a presque 10 ans. Bien
qu’il fût à l’époque à la pointe du progrès, il atteint maintenant la durée de sa vie opérationnelle et a besoin
d’être remplacé. Le système actuel pourrait en effet ne pas être conforme aux prescriptions énoncées dans
la Résolution de l’OMI A.915(22) pour les GNSS futurs et ne pas correspondre aux besoins des
applications qui se font jour avec les développements que connaissent les diverses constellations GNSS.
Ce rapport décrit le projet de restructuration, y compris son déroulement, donne une description des
besoins de l’usager, des options disponibles et de la conception de système choisie, de même que les
progrès réalisés à ce jour sur cet important projet d’aides à la navigation.
INTRODUCTION
The General Lighthouse Authorities of the United Kingdom and Ireland (GLA) is the collective name for
Trinity House (TH), The Northern Lighthouse Board (NLB) and the Commissioners of Irish Lights (CIL),
who between them provide marine aids-to-navigation (AtoNs) around the coast of the United Kingdom and
the Republic of Ireland.
These three authorities, although separate entities, collectively operate, maintain and monitor the operation
of the GLA’s differential GPS (DGPS) augmentation service that broadcasts corrections to the mariner over
a medium frequency signal (283.5-315 kHz).
The GLAs installed 12 of their DGPS stations in the late 1990’s, with a further 2 stations added in 2000
(Figure 1). All 14 stations are identical in architecture and consist of two integrity monitors, two reference
stations, a dual redundant medium frequency (MF)
transmitter and primary and secondary antennas
(Figure 2).
While this is collectively operated as a single aid-tonavigation (AtoN), each GLA controls and monitors the
performance of the reference stations within their
jurisdiction. For example, the three Irish DGPS
stations Mizen Head, Loop Head and Tory Island are
all monitored and controlled at the CIL Monitor Centre
in Dun Laoghaire. In case of disasters, one Monitor
and Control Site can control and monitor the
performace of all GLA reference stations, if required.
Í Figure 14 : Diagram of the United Kingdom and Ireland detailing the location of the GLA DGPS reference stations (blue), the monitor and control stations (orange) and the far field monitor sites (green). 17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 102 Figure 2: Schematic of a GLA DGPS station: two reference stations (RS) and two integrity monitors (IM) provide dual redundancy. Transmitter, automatic tuning unit (ATU) and antenna are also duplicated on site (not shown). Î The GLAs operate this system with an
aim to:
“.. provide an unencrypted DGPS
correction and integrity warning service
covering at least the coastal zone (up to 50 NM. seaward) for users with appropriately designed receivers,
with a service that meets international standards” [GLA DGPS Operating Strategy]. Mariners using this
service can enhance their positional accuracy to better than 5m, often in the region of 1.5-2m; and have
integrity of GPS positioning service.
However, the current differential infrastructure is approaching the end of its design life and as such is
becoming more difficult to maintain and repair and it is important that the GLAs look to the future. At this
time, with the approaching changes in satellite constellations and the development of new navigation
signals, the GLAs commissioned a study to investigate the need for a replacement system; to review the
available options and to make recommendations.
It was important that the potential alternative augmentation systems were assessed as they become
available, such as EGNOS and other methods of delivering differential services, including eLoran (Eurofix)
and the Automatic Identification System (AIS).
Any new system would be planned with developments in GNSS in mind. Capabilities for Galileo,
GLONASS M and GPS L2C and L5 were considered. A Real Time Kinematic solution using carrier-phase
corrections was also a desirable option for providing greatly enhanced accuracy However, there were
known constraints on data rates caused by the bandwidth of the present datalink and also limitations on the
coverage area.
INTERNATIONAL SOLUTION
The GLAs are not the only administration going through this change and whatever solution was to be
adopted would be of interest to other administrations. In addition whatever guise the new system took, it
must meet international requirements.
The current system employed by the GLAs meets all requirements of IMO Resolution 953(23) (Ref. 1),
however it cannot meet the most stringent requirements for applications listed in IMO Resolution 915(22)
(Ref. 2) and it would be preferable for the new system to meet these requirements.
Technically the characteristics of the system were open to change, although broadcasts would need to
maintain use of the current frequency and format so as not to require users to purchase new equipment.
As long as international standards are met, the exact method of implementation remains a decision for the
individual administration, although there may be advantages in sharing technical developments.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 103 GLA RECAPITALISATION STRATEGY
The Recapitalisation strategy adopted by the GLA is largely reflected in IALA Recommendation R-135 “The
Future of DGNSS” (Ref. 3). In order to make an educated decision on their DGPS service, the GLAs
reviewed the available options, which included to:
•
Do nothing
•
Put off a decision until some point in the future
•
Modernise the existing infrastructure
•
Install new infrastructure
The GLAs came to the conclusion that if no action was taken the service would become unreliable, difficult
to maintain and would no longer meet international requirements, therefore this was not an acceptable
approach. If they put off a decision then it would make it more difficult and expensive to re-engineer or
replace the system in the long term when it became essential to do so; again not an acceptable approach.
The system could be modernized, upgrading the existing hardware but there were few potential suppliers
and it was felt that the result might not meet future needs. This could then lead to a proliferation of
additional systems to meet specialized applications and as such the option was discounted.
Another option was to develop a new system to meet future requirements and changes in the core GNSS.
This option would be the strategy most likely to result in a single integrated system meeting a wide range of
applications, whilst maintaining backward compatibility and compliance with existing standards. This was
considered the most suitable option.
RECAPITALISATION OPTIONS
At this stage the GLAs opted to seek advice from independent consultants, who were tasked to investigate
the different options available to the GLAs.
Consultants were asked to consider the requirements of the mariner, to review when new GNSS signals
would become available and also to review the current systems available on the market (Ref. 4)
Their resulting advice was to split the recapitalisation process into two parts, with the first focusing on a
like-for-like replacement in terms of functionality and then a second change in 10-15 years time at which
point new services could be introduced, if required.
The following four replacement options were proposed:
•
Replacement with hardware Reference station and Integrity Monitor (RSIM);
•
Replacement with RSIM implemented in software;
•
Virtual Reference Station (VRS) approach using an existing network and with an RTK option;
•
Integration with Satellite Based Augmentation Systems (SBAS), utilising EGNOS .
The hardware replacement option was the most cost-effective and least risky. Software RSIM had
advantages in terms of flexibility of development, but costs and maintainability were less certain. A VRS
network had a notional cost advantage, but there was no existing network in place, or likely to be
established in the near future which would give the required coverage and reliability. Integration with SBAS
had some advantages in terms of shared infrastructure costs, but the uncertainties were too great for this to
be a responsible choice.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 104 PROCUREMENT
Based on the recommendation of the study into the
available options the GLAs decided to invite tenders
to replace the current network with a hardware
approach.
As discussed earlier in this paper, the GLAs operate
their DGPS network as a single aid-to-navigation
although it is managed by all three Authorities. As
such, one Authority, Trinity House, took on the role of
contract entity and managed the procurement of the
system and subsequent support contract, on behalf
of the three GLAs. A project team with technical,
legal and procurement representation from each GLA
prepared the ITT and contract documents.
Given the nature of the tender and the expected
expenditure, the tender was announced in the
European Journal to give the widest possible exposure.
Fig. 3 – Point Lynas DGPS rack room A number of expressions of interest were received and a series of site visits were conducted to enable
potential tenderers to review some of the more logistically challenging sites, in order to review the scale of
the task at hand.
It should be noted that some of the lighthouses used to host the GLAs DGPS equipment are several
hundred years old and were not build to hold large amounts of electrical equipment, for example Figure 3
details the space for the DGPS rack which is stored within the lamp room at Point Lynas lighthouse.
SELECTED TENDER
All three GLA’s gathered for a week in Dun Laoghaire to objectively assess the submitted tenders in terms
of compliance with the specification, and price. After much assessment it was agreed that the tender which
met the specification and gave best value for money for the GLA’s was that from VT Communications Ltd
of Ashchurch, UK. After a period of contract negotiation to settle the Programme of Work and Payment
Milestones, the contract was officially placed with VT Communications Ltd in August 2008. As part of the
VT offer the reference stations were to be provided by Kongsberg, the transmitters by Southern Avionics
and the commissioning would be carried out by NSL.
Since this time the GLAs have been working with VT Communications Ltd to design and implement the
new system along with any necessary pre-installation works required on site.
Given that the GLA differential stations are predominately located at Lighthouses that are often hundreds of
years old and located in very remote, hard to reach locations; there are a number of additional items to
consider when replacing infrastructure, such as access and egress, where to site equipment and how to
maintain the DGPS service to the mariner during installation.
CURRENT STATUS
In October 2009 the documentation was being prepared for Factory and System Acceptance Tests.
Sitework was in progress, with new and refurbished masts and antennas being prepared for and installed.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 105 The basic system had been assembled and was undergoing proving tests, the user interfaces and
reporting system was in the final design stage.An inter-GLA team is working closely with VTC to ensure the
successful implementation of the project.
FUTURE UPGRADES
The GLA are looking to the future of DGNSS. It is expected that in conjunction with other IALA members
new GNSS services will be reviewed as they become available and future requirements for augmentation
systems will also be kept under review. It may be, that with integrity signals incorporated in future GNSS,
there may no longer be a need for ground-based augmentation. However, the needs of legacy users must
be borne in mind and adequate notice would have to be given before discontinuing such an important
service.
The study on on the need for a second recapitalisation is likely to start within the next few years and any
future system would be expected to cater for multiple signals from several GNSS.
CONCLUSIONS
The continuation of the GLA DGNSS service is assured for the short to medium term. The need to
recapitalise was born out of the need to ensure equipment is maintained to the highest standard and also
that the service provided to the mariner meets the IALA availability requirements as an AtoN and the
parameters set out in the relevant IMO Resolutions.
All alternatives to the beacon system were assessed and the different options for replacement were
considered. It was decided to retain the existing hardware RSIM architecture, but replace it with modern,
more flexible equipment.
REFERENCES
1.
IMO, 2003. Resolution A.953(23) World Wide radio Navigation System.
2.
IMO, 2001. Resolution A.915(22) Revised Maritime Policy and Requirements for a Future Global
Navigation Satellite System (GNSS)
3.
IALA 2008. Recommendation R-135 “The Future of DGNSS
4.
Pattinson, Dumville & Ward, 2007. Options for the Modernization of Maritime DGNSS, European
Navigation Conference, Geneva 2007.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 106 The Use of an Under Keel Clearance Management System as an Aid to Navigation in the Torres Strait Mahesh Alimchandani, Australian Maritime Safety Authority, Australia ABSTRACT
Under Keel Clearance Management (UKCM) systems are being increasingly adopted at ports, both as a
means to enhance the safety of navigation and to increase the efficiency of shipping transportation.
Navigation in the Torres Strait is very demanding due to limiting depths, narrow shipping lanes and
numerous reefs, coral cays & islands. Additionally, transiting ships can expect to encounter strong tidal
streams and trade winds, complex tides and reduced visibility in the wet season, as well as occasional
cyclones.
The Australian Maritime Safety Authority (AMSA) has recently embarked on the implementation of a UKCM
system for the Torres Strait. The objectives for introducing UKCM are to validate the existing safety margin
for deep draught vessels transiting the region and evaluate the appropriateness of the current maximum
draught limitations.
It is expected that the UKCM system will enhance the safety and efficiency of navigation which will help
protect the sensitive marine environment. This in turn will benefit the Australian community and shipping
industry.
UKCM in the Torres Strait is perhaps among the first few being deployed in a coastal environment.
The paper will describe the operational model for UKCM, as envisaged by AMSA. It will also describe the
business services required of the system and the various utility services to support those business needs.
RÉSUMÉ
Les systèmes de gestion de la profondeur d’eau libre sous la coque (UKCM) sont de plus en plus en usage
dans les ports, comme moyens d’améliorer la sécurité de la navigation et d’accroître l’efficacité du
transport maritime.
La navigation dans le détroit de Torres est très difficile en raison de profondeurs limitées, de voies étroites
et de nombreux récifs, coraux et îlots. En outre, les navires y transitant doivent s’attendre à de forts
courants de marée, des vents forts, des marées complexes, une visibilité réduite pendant la saison des
pluies et, occasionnellement, à des cyclones.
L’Autorité australienne de sécurité maritime (AMSA) a récemment entrepris le mise en œuvre d’un système
UKCM pour le détroit de Torres, avec pour objectifs de valider la marge de sécurité existante pour les
navires à fort tirant d’eau naviguant dans la région et évaluer le bien-fondé des limitations de tirant d’eaux
actuellement en vigueur.
On peut attendre du système UKCM qu’il améliore la sécurité et l’efficacité de la navigation, ce qui aidera à
la protection d’un environnement particulièrement fragile. Ce qui, en échange, bénéficiera à la
communauté australienne et à l’industrie maritime.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 107 L’UKCM du détroit de Torres est peut-être l’un des tout premiers déployés dans un environnement côtier.
La présentation montrera le modèle de fonctionnement de l’UKCM tel que l’envisage l’AMSA. Elle décrira
aussi la chaîne de services requise par le système et les sous-ensembles nécessités par cette chaîne de
services.
1. AN INTRODUCTION TO
THE TORRES STRAIT
Named after the first known
European explorer in the
region, Spanish navigator
Luis Baés de Torres, who
sailed through the area in
1606, the Torres Strait lies
between the northern-most
point of the Australian
continent and the island of
New Guinea. It is bound to
the west by the Arafura Sea
and the east by the Great
Barrier Reef (GBR) and the
Coral Sea. It is, in very
general terms, about 140
nautical miles long and 80
nautical miles wide (see
Figure 1).
The Torres Strait has been
described as ‘the most
extensive, ecologically
complex shelf in the world,
offering a multitude of
habitats and niches for the
great diversity of Indo-Pacific
marine fauna’1. It has an
overall population of about
8000, of which approximately
6000 are Torres Strait
islanders and Aboriginal
people. They maintain a
strong bond with the sea
through their culture, lifestyle
Figure 1 – The Torres Strait Region 1
McGrath, V Contemporary Torres Strait Art, essay in Ilan Pasin catalogue.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 108 and history.
The Torres Strait is a major shipping channel for Australia and Papua New Guinea (PNG). Navigation
through the Torres Strait is very demanding. The passage involves transiting confined waters with limiting
depths, particularly in the western section. Gannet and Varzin Passages have depths of 10m and 10.5m
respectively at chart datum.
The strait experiences a highly variable and complex tidal regime and fast flowing tidal streams - up to 8
knots have been experienced in the Prince of Wales Channel. Dominating the climate is alternating wet
and dry seasons. Visibility is frequently affected by seasonal rainsqualls. The whole area experiences
moderate to strong winds, tropical thunderstorms and occasional cyclones.
The Torres Strait and Inner Route of the GBR are used by a range of craft, from trawlers and pleasure craft
to general cargo vessels, bulk carriers and large tankers. All but the smallest vessels are confined to a few,
well-defined routes that are potentially hazardous to navigation. The majority of the routes are very narrow,
confined by many charted dangers, limited depths and strongly influenced by tides and tidal streams.
The grounding of the Oceanic Grandeur in 1970 resulted in some 1100 tonnes of oil being spilt. The most
significant impact was the instant destruction of the region’s thriving cultured pearl industry. It has never
been revived. The grounding led to three safety initiatives. They were:
•
A highly detailed hydrographic survey, that took over a year to complete, and made the first use of
side-scan sonar in Australia. This survey of 1971 has stood the test of time, and has been validated
by the most modern technology in use.
•
The establishment of 4 transmitting tide gauges, which give mariners real-time tidal heights via VHF
radio. This is necessary, as the tidal height frequently deviates from that predicted in tide tables,
owing to fluctuations in mean sea level and meteorological factors.
•
The introduction of draught and under keel clearance limits.
2. BACKGROUND
AMSA is an Australian Government regulatory safety agency with the primary role of delivering services in
relation to maritime safety, aviation and marine search and rescue and protection of the marine
environment.
In the context of navigation safety, AMSA’s primary responsibility includes the provision of the national aids
to navigation network and navigational systems. One of the strategic objectives in this regard is to adopt
technological advances to improve navigational safety.
Australia, being remote from major world suppliers and markets relies heavily on sea-borne trade.
Shipping, which is among the most international of industries, is therefore extremely important to the
Australian economy. Over 95% of Australia’s trade by volume is carried by sea and a large proportion of
this is in ships that transit the Torres Strait and the GBR.
3. THE CASE FOR AN UNDER KEEL CLERANCE MANAGEMENT SYSTEM
In recent years, vessel operators have requested AMSA to re-examine the prevailing draught limitation of
12.2m in the Torres Strait. The general expectation from industry is that a UKCM system will permit
vessels with draughts greater than 12.2m to transit the Torres Strait safely on certain days (bathymetric
and met-ocean conditions permitting). An increase in the maximum permissible draught will offer
significant economic benefits. This will result in a positive impact on the Australian economy.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 109 AMSA had earlier deferred addressing the issue of draught restrictions, as there was low uptake of pilotage
in the Torres Strait. Also, it was recognised that highly accurate modern hydrographic surveys would be
required.
AMSA recognises that the UKCM system will be an aid to navigation, one that will provide vessels and their
coastal pilots with tidal windows and transit plans using predicted, historic and real-time met-ocean inputs.
The system will, in conjunction with AMSA’s rules for maximum draughts and a minimum net UKC, assist a
vessel to transit the Torres Strait more safely and efficiently.
In 2006, AMSA commissioned Thompson Clarke Shipping Pty Ltd to undertake a study on the
implementation of a UKCM system for the Torres Strait. The study found that an AMSA-managed UKC
system would provide the means to obtain a more accurate assessment of the margin of safety. It would
also provide the basis for any future changes (increase or decrease) to the current draught limitation of
12.2m.
AMSA has considered alternative delivery methods for UKCM and consulted industry. In response to the
recommendations of The Delivery of Coastal Pilotage Services in the Great Barrier Reef and Torres Strait,
Review Panel Report October 2008, AMSA has decided that a single under keel clearance management
(UKCM) system for use in Torres Strait be selected through an open tender process.
Therefore, there will be one supplier of the system. AMSA has decided that the UKCM system will be used
for the management of all transits of vessels whose draught is eight (8) metres or greater.
The selection process was completed in December 2009. OMC International Pty Ltd (OMC) has been
selected as the preferred supplier for the provision of the UKCM system. OMC is a Melbourne-based
UKCM service provider, considered to be one of the world’s leading suppliers of such systems.
3.1 – The objectives
The objectives for introducing UKCM are to deliver enhanced safety and efficiency of navigation by:
•
Validating the existing safety margin for deep draught vessels transiting the region; and
•
Evaluating the appropriateness of the current draught regime.
This will further benefit the Australian community and industry and help protect the sensitive marine
environment.
4. OPERATIONAL OVERVIEW
4.1 – Area of operation
The UKCM area in the Torres Strait is defined as the navigable channels between the longitudes of 141
degrees and 50 minutes East and 142 degrees and 27 minutes East (Figure 2 in the Annex). In this area,
the current official least depths at Lowest Astronomical Tides (LAT) relevant to the operation of a UKCM
system are as follows (Figure 3 in the Annex refers):
•
Varzin Passage:
10.5m
•
Off Goods Island:
11.3m
•
Nardana Patches:
11.6m
AMSA will regulate UKCM in the Torres Strait and manage the provision of the UKCM system. The UKCM
system will provide a robust mechanism for pilotage providers ashore to generate, on demand, tidal
windows and transit plans for a vessel intending to transit the Torres Strait. The coastal pilots must utilise
the UKCM system as a tool for conducting passages of deep draught vessels through the region.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 110 4.2 – Operational stages
It is envisaged that UKCM in the Torres Strait will operate in three stages. These are outlined below:
Voyage Planning Stage: In this stage, authorised users will be able to conduct advance planning
for the possible transit of a vessel by calculating the maximum draught and associated tidal
windows (in conjunction with AMSA’s rules for draught and net UKC). The UKCM system will make
use of vessel particulars and predicted met-ocean inputs.
Transit Planning Stage: In this stage, pilotage providers will be able to generate (and update), on
demand, a tidal window and associated transit plans for an intended transit. The UKCM system will
use predicted vessel motion and met-ocean inputs, but these will be refined using the latest realtime inputs available.
UKCM Assisted Transit Stage: When transiting the area, the pilot on board will use a Portable
Pilot Unit (PPU) linked to the UKCM system ashore. This will allow the pilot to make adjustments to
the transit plan on board, as required, in real time.
4.2.1 - Voyage Planning Stage
The UKCM system will provide a long term voyage planning capability. The UKCM system will provide the
capability to calculate, for any given vessel and date, the maximum draught and associated tidal windows
(in conjunction with AMSA’s rules for draught and UKC2).
The UKCM system will make use of predicted met-ocean conditions and vessel particulars. It can be used
to explore ‘what if’ scenarios. This capability will be provided for up to twelve months prior to a vessel’s
arrival at the UKCM area. This stage may be used to assist in the making of decisions on the routeing of
vessels through the Torres Strait.
4.2.2 - Transit Planning Stage
The transit planning stage commences once a ship manager/master notifies a pilotage provider of the
intention to transit the Torres Strait. The UKCM system will provide the capability to:
•
Enable a pilotage provider to generate tidal windows, transit plans and the minimum net UKC on
demand;
•
Calculate predicted vessel motion and its effect on net UKC;
•
Automatically update the tidal windows and transit plans based on the latest met-ocean information
available;
•
Electronically compare and highlight any changes to the tidal windows and transit plans for a given
vessel;
•
Monitor the vessel’s progress against the transit plan;
•
Validate the vessel’s particulars against SHIPSYS (IMO number, name and call sign);
•
Automatically export the latest transit plan information electronically to REEFVTS; and
2
Marine Order Part 54 states that a pilot must not pilot a ship through the Prince of Wales Channel or the Gannet and
Varzin Passages unless the ship:
(a) has a draught that does not exceed 12.2 metres; and
(b) has a net minimum under keel clearance of:
(i) if the ship is in the Prince of Wales Channel and has a draught of less than 11.90
metres — 1.0 metre; or
(ii) if the ship is in the Prince of Wales Channel and has a draught of 11.90 metres or
greater — 10% of the draught of the ship; or
(iii) if the ship is in the Gannet and Varzin Passages — 1.0 metre.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 111 •
Allow multiple authorised users to view the transit plan of a vessel.
4.2.3 - UKCM Assisted Transit Stage
The UKCM assisted transit stage commences as a vessel enters the UKCM area and the pilot is on board.
Under this stage, a pilot can access the UKCM system on board, in real time, to update the transit plan.
The UKCM system will provide the capability to:
•
Automatically update the transit plan and net UKC at regular, predefined intervals, taking into
account real-time met-ocean information, vessel’s position and speed;
•
Enable the pilot on board to make adjustments to the transit plan using a PPU;
•
Ensure both the PPU and the UKCM system ashore are updated simultaneously when any changes
are made to the transit plan;
•
Electronically compare and highlight any changes from the previous transit plan generated; and
•
Allow multiple authorised users to view the transit of the vessel through the UKCM area, to ensure a
pilots’ adherence to the active transit plan.
4.3 - Implementation
At the outset, the system will be for use by coastal pilots and pilotage providers only. This will allow a
controlled introduction of this new technology including making it easier to deal with any teething problems.
Noting this, access to the Voyage Planning Stage is expected to be extended to ship operators once AMSA
has sufficient confidence in the operation of the system.
Initially, AMSA plans to implement the Voyage Planning and Transit Planning Stages only. Any future
implementation of the UKCM Assisted Transit Stage will be subject to the approval of a business case by
AMSA.
4.4 - Role and responsibilities
Table 1 below is an outline of the role and responsibilities of the key stakeholders. Entity
Role/Responsibility
Shipping company/agent
Provide the required vessel particulars including hydrostatic details and ETA at
the UKCM area to the pilot provider.
Master
Provide the required final stability particulars prior to the pilot boarding/transiting
the area.
Coastal Pilots/pilotage providers
Utilise the UKCM system. Manage tidal windows and transit plans for the vessel.
AMSA
Oversight the use of the UKCM system by pilot providers in accordance with
Marine Order Part 54.
Provide validated sensor data for use by the UKCM system.
Provide pilotage provider/pilot access to the UKCM system.
UKCM provider
Ensure contracted service is provided to AMSA including delivery to the specified
performance and availability criteria.
REEFVTS
Provide UKCM-related information, as part of the on-going delivery of an
3
Information Service , in a manner consistent with IMO Assembly Resolution A
(857) 20 Guidelines for Vessel Traffic Services.
3
An Information Service is a service to ensure that essential information becomes available in time for on-board
navigational decision making.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 112 5. KEY FUNCTIONALITY
To support this operational model, a system is required that will have the following functionality:
•
•
•
•
Provide accurate tidal windows and transit plans based on:
o vessel’s particulars, including hydrostatic information;
o the net UKC requirements prescribed by AMSA;
o depth data, as provided by the Australian Hydrographic Service;
o predicted and real-time met-ocean information; and
o predicted vessel motion.
Incorporate a comprehensive input data validation and system integrity regime.
Ability to exchange information with REEFVTS; and
Provide information for operational oversight and management reporting to AMSA.
5.1 - Inputs
The UKCM system will have access to a set of predictive, historic and real-time met-ocean input data from
sensors maintained by AMSA in the Torres Strait. This will be required to calculate voyage and transit
plans. The input data for UKCM is summarised in Table 2 below:
Table 2: Data import summary Providing Service /
System
Data provided
Receiving Service /
System
Intended use
SHIPSYS (AMSA)
Vessel particulars from
AMSA’s SHIPSYS system.
UKCM (AMSA)
To initially populate and
periodically update vessel
particulars.
AtoN (AMSA)
Met-ocean data from
various sensors in the
vicinity of the Torres Strait.
UKCM (AMSA)
As input to transit planning
calculations.
AMSA / Bureau of
Meteorology (BoM) /
Australian Hydrographic
Service (AHS)
Official met-ocean
predictions
UKCM
Initially provide and regularly
update predicted met-ocean
data for locations in the vicinity
of the Torres Strait.
AIS data (AMSA
Vessel positional
information
UKCM
Enable the system to predict
variation from a transit plan or
breaches of net UKC.
AHS
Official bathymetry data
UKCM
Initially provide and regularly
update the bathymetry for the
navigable channels within the
UKCM area.
5.2 - Outputs
The UKCM system will, for a given draught and speed, produce tidal windows, transit plan and the
minimum net UKC. The net UKC will be produced for the entire length of the chosen route in the UKCM
area. An output will only be produced when all input parameters have been entered and validated. The
presentation of information will be easy to read and understand and be able to be printed on a single page
of paper (A4 size) and in a format that is suitable for facsimile and electronic mail transmission.
The UKCM system will be able to exchange key system and vessel-related information with third party
systems.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 113 6. OVER VIEW OF SYSTEM REQUIRTEMENTS
6.1 - Business services
Four main business services are required of the UKCM system. They are:
1. Registration Service: This is a service to support the management of registering user details. Mainly,
this service is about ensuring that the UKCM system is only available to authorised users in a secure
manner.
2. Vessel Service: A service to input and maintain vessel particulars. This service enables new vessel
particulars to be recorded in the system. Particulars for existing vessels records can be sourced from
other systems and maintained in the UKCM system.
3. Voyage Planning Service: A service to support the long term planning of transits through the Torres
Strait. Voyage Planning Service allows ship operators to explore ‘what-if’ scenarios and determine
maximum safe draughts and associated tidal windows. It includes the determination of a maximum
safe draught for a transit and tidal windows.
4. Transit Planning Service: A service to support the planning of transits through the Torres Strait.
Includes determination of maximum draught for a transit, times at key way points (and speeds to make
good those way points) and the resultant net UKC throughout the transit. Transit Planning Service
Pilotage providers and coastal pilots have up-to-date information on the predicted minimum net UKC
determined for a particular transit of the Torres Strait.
6.2 - Utility services
A set of utility services will support the business services in the UKCM system. Table 3 below summarises
the suite of utility services that will be available in the system.
Table 3: Summary of utility services Service
Description
Business Outcomes
Data Validation Service
Service to monitor and validate input
and output data
Only valid data is used to calculate outputs.
Only valid outputs are produced.
Business Messages
Service
Service to monitor business messages
Messages are generated when certain business
events occur.
System Monitoring
Service
Service to monitor and report on the
components of the system.
Components that are malfunctioning or
unavailable are reported and addressed.
The system administrator is informed of any
mal-function or unavailability of the system that
compromises the reliability of the outputs.
System Administration
Service
Service to support the management of
users, system configuration parameter
and code details.
The system administrator can allow varying
levels of user access
System parameters and code and are kept upto-date to support other UKCM functions.
Reporting Service
Service to support the request of
standard and generic reports.
UKCM data can be reported on to support
operational and/or analysis activity.
Security Service
Service to support the management of
system security.
UKCM functions and data are appropriately
secured.
Help Service
Service to support the provision of
electronic help.
Users have electronic assistance on the use of
system.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 114 Service
Description
Business Outcomes
Data Import Service
Service to support the import of
information required for the UKCM
system.
Vessel, hydrographic and met-ocean data is
imported efficiently.
Data Export Service
Service to support the export of UKC
data.
Voyage and transit plans can be exported and
printed efficiently.
Data Management
Service
Service to manage the efficient
storage, organisation and retrieval of
UKCM data.
An accurate record of UKCM data including
transit plans is maintained and is easily
retrievable.
Efficient delivery of UKCM data to stakeholders.
7. IMPLEMENTING THE UKCM SYSTEM
It is expected that the UKCM system in the Torres Strait will be operational by the end of this year.
Implementing the system will involve a number of ‘sub-projects’. In no particular order of importance, some
of the major ones are listed below:
7.1 - Validation of the UKCM system
Initially, an independent third party will be contracted to validate the output of the operation of the UKCM
system. This will be required prior to trialling it on a range of transiting ships and finally declaring it
operational. Subsequently, independent validation will be required to be carried out on a periodic basis.
7.2 - Development of Standard Operating Procedures
Standard Operating Procedures or SOPs will need to be developed, so that shipmasters, pilots, the system
provider, AMSA and REEFVTS have a common understanding of the manner in which the system is to be
used.
7.3 - Communications Plan
A communication plan will need to be developed. This will aim to inform shipmasters, coastal pilots,
pilotage providers, the shipping industry and other stakeholders of the UKCM system.
7.4 - Revision of Marine Order Part 54
AMSA will enforce the use of the single UKCM system by the coastal pilots and pilotage providers through
Marine Order Part 54. Marine Orders are subordinate legislation created under the regulation making
powers of the Navigation Act 1912. In general, Marine Orders provide the specific or technical
requirements that are to be implemented or adhered to.
7.5 - Validation and calibration of AMSA’s sensors
AMSA will put in place a regime to verify the accuracy of sensor data and periodically re-calibrate all
sensors, independent of the contractor.
7.6 - Liaison with the Australian Hydrographic Service
AMSA will work closely with the Australian Hydrographic Service (AHS) to ensure that high accuracy
surveys as required by the UKCM system are available.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 115 8. CONCLUSION
The waters of the Torres Strait are hazardous to shipping, particularly for vessels under the command of
those unfamiliar with the conditions in the region. The vulnerability of the environment of the strait to
pollution damage, and the reliance of the indigenous people upon that environment, makes the Torres
Strait an area of great concern in the context of maritime safety.
Over the years, Australia has put in place several measures with the twin objectives of enhancing the
safety of navigation and protecting the marine environment.
Under keel clearance management systems are a current generation innovation, one that can contribute to
safety and efficiency (by permitting deeper draught vessels) to transit the region.
ANNEX
Figure 2 – Area of UKCM operation 17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 116 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES 17ème Conférence de l’AISM Figure 3 Page 117 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Birds Plague Laser Control and WiFi Technologies Applied to Environmental Control Improvement in Port Areas Enrique Bernabeu, La Maquinista Valenciana SA, Spain ABSTRACT
Environmental control is part of our responsibility for the next times. LMV tries to approach new
technologies available on the market to solve problems existing in port areas.
Communication system which will allow free of charge-real time communication with hundred devices
inside a port area with 50km radio over a private IP network using wifi/wimax/zigbee technologies, including
transmission of pictures and video in real time will be available very soon.
We will show just one of the first practical applications proposed to implement thanks to this technology.
Environmental control buoy to establish a network of sensors for water quality control in port areas.
On the other hand, we will try to solve a traditional problem in port areas related to store grain : Birds, from
cormorants, to seagulls have always been an unavoidable problem and LMV presents a new laser
technology already applied in airports to reduce this problem without damaging the birds and respecting
environmental policy about this.
RESUME
Le respect de l’environnement fait partie de nos responsabilités pour les années à venir. La Maquinista
Valenciana (LMV) essaie les nouvelles technologies maintenant sur la marché pour résoudre les
problèmes rencontrés dans les zones portuaires.
Un nouveau système de communication sera bientôt disponible, qui permettra de communiquer
gratuitement en temps réel avec des centaines d’appareils d’une zone portuaire, sur 50 km, à l’aide d’un
réseau IP privé utilisant les techniques WiFi/wimax/zigbee. Il permettra aussi de transmettre des photos et
des vidéos en temps réel.
Nous allons montrer une de ces premières applications pratiques : un bouée de contrôle de
l’environnement permettant d’établir un réseau de capteurs pour le contrôle de qualité de l’eau dans les
ports.
D’autre part, nous nous efforcerons de résoudre le problème ancestral des zones portuaires : le stockage
de grain. Les oiseaux, du cormoran à la mouette, ont été inévitables ; LMV offre une nouvelle technologie
laser, déjà appliquée dans les aéroports pour minimiser ses effets sans nuire aux oiseaux et respecter
ainsi les politiques d’environnement.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 118 WFI TECHNOLOGIES APPLIED TO ENVIRONMENTAL CONTROL IMPROVEMENT IN PORT AREAS
1. Review on wifi technologies available.
Wifi networks based on standard 802.11a/b/g have experimented an spectacular growing during the last
times. During the last years these technologies have entered our daily life. This has permitted reduction of
costs and continuous improvement of the benefits supplied.
Communication networks based on wifi technologies offer very valuable benefits as mobility, flexibility,
reduction of operation costs and scalability of the proposed systems.
Bandwidth capability, distance reached and nodes intelligence to work as repeaters are the three main
areas of investigation around this technology, giving concepts like WIMAX or ZIGBEE networks.
Many different applications are implemented thanks to this new technology, but the one most known and
main responsible of this development has been implementation of IP networks to connect to internet.
Access on real time to information available at the other side of the network is a very valuable benefit, and
it is a well established and proved technology to allow
us a new line of research to use it in port areas.
Even being this technical solution valid to solve many problems, we have focused this study in designing a
solution for an IP network of sensors implemented to measure environmental parameters in port areas.
2. Sensor`s IP network.
The first step was designing and adapting an existing 802.11b/g device to our needs. The main objectives
reached during design and implementation of this communication tool for this purpose have been the
following:
•
The wifi device operates with different manufacturers of sensors.
•
The system will be installed together with the subacuatic sensors, over one buoy, or in a fixed network.
•
The system is powered by the same solar panels existing in the buoy or by his own solar panel system.
Consume does not exceed 100mA.
•
The wifi device will has several serial programmable interfaces, and works under LINUX.
•
The wifi device will be the first step for intelligent nodes, so they have process capability.
With this objectives reached we have saved the bigger initial problems, power supply of the system
installed in a buoy, and capability to connect to any sensor. ( See point three “Sensors”.)
3. Design of the network and web interface.
The second was designing one network and WEB application to receive, interface, store and process the
information given. The requirements were:
•
The network will allow to select and identify easily each sensor.
•
All the information will be stored and processed in a control centre located anywhere connected to the
IP network.
•
There will be no limits for upgrading number and type of sensors.
•
Access to information will be flexible and customized for costumer requirements.
•
Environmental limits programmable depending on local rules.
•
Software capable to compare information from different points and statistic applications.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 119 With this design, and by means of some WIFI commercial antennas and repeaters ( depending on the
distance required to be covered) we can create our own network in which each device “hanged” on it will
have the consideration of an IP Point.
Access, management, and supervision of each device will be done in real time through a webserver with
main/standby capability. This server, which can be located in the costumer network or outside will process
and present the information, reports, statistics, control of users, passwords, automatic or periodic actions,
etc…
4. Sensors.
With the technology implemented, and with some own design electronic interfaces, it is possible to
integrate several kind of sensors with different technologies.
a) Water quality sensors ( temperature, PH, Oxigenometry, Sedimentation).
b) Meteorological stations (wind, pressure, etc.)
c) Doppler systems.
d) Spectrophotometer systems.
e) Security sensors ( accelerometer, Infrared detectors, volumetric detectors, etc.)
f)
Remote control ATON applications. All the typical parameters for remote control and management
of beacons, rotating beacons, etc).
Being these sensors made by many different companies and with different technologies we will be able to
integrate any working with analogical or digital Inputs and outputs, also serial interfaces and other
standards.
5. Direct Benefits.
Due to the implementation of an IP network with our sensors or devices, we obtain directly plenty of
advantages witch easy maintenance jobs and reduce costs offering a continuous operation of the systems
connected to this network.
a) Save costs. No operation costs for each communication as in GSM/GPRS/SAT systems.
b) Possible real-time 24/7 available information for the costumer.
c) Main/standby communication available WIFI/GPRS or WIFI/SAT.
d) No external public network involved. Information is private and secure.
e) Multiuser/multiacces available from several PC´s connected to the network.
f)
No software license required to install in the PC. Just Internet explorer or similar.
g) Any Operative system operation, any version, any windows, any UNIX.
6. Future applications.
As soon as WIMAX/ZIGBEE technologies and intelligent nodes are available, the bandwidth available will
increase and optimise, which will allow us to many very interesting applications:
a) Transmit video real time (spy buoys or security buoys).
b) Use of thermal cameras to watch sea borders.
c) Connect nodes between themselves, reducing installation of infrastructure (antennas and
repeaters).
d) Increase coverage area and optimise availability of the ATON and environmental systems.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 120 e) International network of sensor for water quality control.
7. Practical application. Environmental control water quality parameters in port areas.
Regarding the existing environmental control policy in most part of the world, and water quality is one of the
most important, not just only for human consume, but for the growing of fishing-farms, protected and
reserved areas, hidrocarbures pollution, petrol accidents, poisoned verts, industrial and chemical trash,
etc…
Actual procedures to make detailed tests of this parameters or detection of dangerous substances is too
slow, as normally a laboratory and a take of samples is included.
Until now, these kind of parameters can also be measured through very expensive sensors, which are
normally quite specific. So you must acquire one sensor for each thing you want to control.
Normally each one has its own modem system, normally based on GPRS or CDMA networks, and its own
monitoring software, which comes with its own license and must be installed in a PC connected to the
antenna.
In our proposal, the sensors will be installed together with our device in one buoy, which will be fond in the
port, every sensor will interface with our modem, and we will access to the information given by the sensors
through one website, with no cost of transmission and in real time.
In case of sensors which allow remote operation, and just in case we are authorised by the system
administrator, we will be able to change the state of the sensor, reset, etc…
In order to save energy, our intelligent node will turn off and go to sleep mode in case no tx is necessary,
we will wake it up in case of an alarm or required update of information.
With the proposed system the Environmental department responsible of the port will have detailed and real
time information about the parameter of interest in his area.
With the statistic and meteorological application, long term evaluation will be possible, and will help to
prevent disasters, improve plague control, pollution, etc…
8. Maintenance requirements
Unfortunately, the required maintenance and cost of the sensors are the weak part of this application, so
until the moment technology is still expensive.
Each sensor is composed and designed for a very detailed application, and as far as we know no general
purpose kits are available until the moment at a reasonable price.
On the other side, maintenance of the network is almost free and offers many benefits.
9. Comparison of costs.
Without being exhaustive, cause prices change too much form one side of the world to other,
implementation of an WIFI network is same as radio station or cheaper, wifi devices are just 25% more
expensive than GPRS modems, and cost of operation and maintenance are almost zero, compared with
any previous technology.
10. Cooperation.
This project has been implemented in strong cooperation with Universidad Politecnica de Valencia,
Department of Coastal Management Research (IGIC). Project managed by Prof. Jaume Lloret.
This Project has been financed by IMPIVA with FEDER funds.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 121 NEW LASER TO FRIGHTEN AWAY BIRDS
1. Advance in technology Laser Research.
There have been recently several applications to the laser technologies. On of these advances has been
already installed in the airport area with great success.
As problem of birds is existing since the beginning if the times with no definitive solution until the moment,
there are plenty of different systems to solve it with more or less success.
From using domestic falcons, to reproduce especial sounds of bird repellers, as examples of limited and
expensive products existing to solve this. We don’t mention aggressive methods cause
Actually, it has been demonstrated that certain frequencies of laser correctly adapted may disturb birds in
dark areas.
2. Description of the need.
During IALA Copenhague 2008 was the first time LMV mentioned this technology in an IALA forum and a
lot of request were coming to us immediately.
There are plenty of problems regarding birds and their acid excrements almost in every part of the world,
while at the same time, environmental respect and non aggressive methods must be used.
One of the request with worst problem are grain store areas in ports. Tones of wonderful grain inside huge
almost open buildings very close to the port are a wonderful paradise for any kind of bird.
Previous methods have demonstrated some positive effects, but the problem is still very big. In some cases
in Valencia, they have done more than 20 thousands captures a year with almost no useful results. There
are several more companies doing the same.
Places to store grain are normally half/opened and have continuous operation which makes difficult to have
these structures closed.
The result is excrements, cadavers of birds over grain with the high risk for health it means and the growing
of epidemics.
3. Definition of device and application.
The conditions in which this problem appears are specially designed buildings close to the port, which
receive and distribute grain coming from the vessels by means of a network of transport belts.
This makes huge and dark areas with no more light than the coming from the lateral apertures, upper
structure 20 up to 20 meters high with metallic structure were hundreds of birds are resting, a cloud of dust
coming from the distribution of grain is in the air.
Different kinds of mountains of grain are separated by 5m high walls making several departments inside
the same building.
The conditions available are perfect, laser works much better with more contrast, so darkness and dust are
really good propagation conditions.
It is demonstrated that under these conditions and for a specially designed laser, birds recognise this light
as a solid, trying to avoid it all the time.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 122 4. First on site tests.
As first step, we will design and manufacture a portable laser with the characteristics mentioned, to check
its efficacy in grain store areas.
For the portable solution we used a single ray portable system with 50mm diameter, green light powered
with commercial batteries.
Our objective is analysing the effect of this laser over birds inside this grain store.
The main results obtained are:
-
Birds don’t like this light!!!
When birds are pointed directly with this light it makes them feel uncomfortable and look for a more
comfortable place. As soon as the light moves after him he will leave the building for some time.
After moving this laser inside the building, specially in the upper part, for two or three minutes, the
building is almost empty.
-
Birds return.
When light disappears, or while you are pointing the other side of the building, birds will go on entering
the site, but while laser is turned on and moving, the effects are quite significant.
-
Area to cover.
The area to be “defended” against birds seems to be too much bigger, and with plenty of opportunities
to come in and go out free for the birds.
-
Speed of movements.
It seems to work better working under stable speed than in accelerating or decreasing speed
procedures.
Conclusions:
The application of this solution is valid for the proposed objectives. It can be shown that a continuous
operation of this laser with several rays/ trajectories/ power will reduce in a big percentage the
presence of birds in these areas.
Motorised, self controlled solar power supply system with several rays, and power configuration maybe
a good solution.
5. Environmental consideration.
This kind of system for repelling birds has demonstrated that no damage is made to the birds, so it respects
the environment.
6. Legal aspects.
Depending on the normative of laser use on open and close areas laser can be adapted to the maximum
power allowed, and a recommendation of the security tools obligatory will be done.
7. Cooperation.
This project has been done in close cooperation with AIDO (Institute of optics, Spain).
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 123 Assessment of shoal bank movements via Earth Observation, related to re‐positioning needs for Aids‐to‐Navigation Michelle De Voy, Martin Bransby, Alan Grant and Sally Basker, The General Lighthouse Authorities of the United Kingdom and Ireland, Ian Thomas and Gordon Keyte, British National Space Centre, UK BIOGRAPHY
Miss Michelle De Voy is a Trainee Development Engineer for the Research and Radionavigation Directorate
of the General Lighthouse Authorities of the UK and Ireland. She received the degrees of BSc in Physics and
MSc in Oceanography from the University of Exeter and the University of Southampton respectively, and is
currently studying for an MSc in Satellite Positioning at the University of Nottingham. She is a member of the
Institute of Engineering & Technology, an Associate member of the Institute of Physics and a student member
of the Royal Institute of Navigation.
Mr Martin Bransby is the Manager of the Research and Radionavigation Directorate of the General
Lighthouse Authorities of the UK and Ireland. He is responsible for the delivery of their project portfolio in
research and development in such areas as AIS, eLoran, eNavigation, GNSS and Lights. He is an Associate
Fellow of the Royal Institute of Navigation, and holds memberships of the Institute of Engineering &
Technology, the US Institute of Navigation and the International Loran Association.
Dr Alan Grant is a Principal Development Engineer for the Research and Radionavigation Directorate of the
General Lighthouse Authorities of the UK and Ireland. He is responsible for GNSS projects within the
directorate. He received the degrees of BSc and PhD. from Staffordshire University and the University of
Wales respectively. He is an Associate Fellow of the Royal Institute of Navigation, a member of the US
Institute of Navigation, and is a Chartered Physicist.
Dr Sally Basker is the Director of Research and Radionavigation for the General Lighthouse Authorities of
the UK and Ireland where she is responsible for the research and development of physical and radio AtoNs,
support systems and their integration. Dr Basker was awarded a PhD for “The determination of mean sealevel using GPS” from the University of Nottingham in 1990 and a BEng (Hons) degree in Civil Engineering
from the University of Nottingham in 1986. She is a Fellow of the Royal Institute of Navigation, a Member of
the US Institute of Navigation, a Director of the International Loran Association, a Member of the GPS World
Editorial Advisory Board, a Member of the UK Department for Transport’s e-Navigation Strategy Group, and a
Member of the IALA e-Navigation Committee.
Dr Ian Thomas has over 30 years experience in leading and supporting user applications programmes,
primarily at government agency level at national and international levels. He has concentrated on the outputs
from airborne and satellite optical sensor systems through their calibration and information content into
processing to support specified user objectives. He has extensive field experience mainly in land cover,
agriculture, mapping and polar studies, with reports in reviewed and limited circulation areas. He is currently
the technical facilitator and assessor from the “space” side on behalf of the BNSC and to the GLAs.
Dr Gordon Keyte has been involved with microwave remote sensing for some 30 years, having led the
development, instrumentation and analysis programmes within the UK Royal Aircraft Establishment and its
successors. He has advised the British National Space Centre (BNSC) on Synthetic Aperture Radar (SAR).
He has also represented BNSC on these topics within European Space Agency programmes and on the
international Committee on Earth Observation Satellites (CEOS) in SAR calibration and validation activities,
including convening discussions at inter-government level within the UK. He has published widely in peer
reviewed journals and in limited circulation reports, with extensive experience of SAR interactions within the
marine environment. He is currently a technical adviser to both BNSC and the GLAs as part of a joint GIFTSS
project on the utilisation of SAR for the GLAs.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 124 ABSTRACT
The General Lighthouse Authorities of the United Kingdom and Ireland (GLAs) and the British National
Space Centre are collaborating, through the UK Government Information From the Space Sector initiative,
to determine if satellite Earth Observation (EO) techniques can be used to monitor dynamic shoal
environments.
Initial work shows that Synthetic Aperture Radar imagery can be used to show the location and shape of
shoals and can be obtained in all weather conditions and at night. The aims of the assessment are: to
identify if a change in a shoal has occurred; detect changes in shoal morphology; and the effect of this
change on the surrounding shoals near navigable channels. The outcome of the assessment will determine
whether examining EO data could be a tool in cost-effective scheduling and reduction of in-situ monitoring
by survey vessels.
This paper will outline how growth in marine leisure activities, the proliferation of high-speed craft and
changes in traffic patterns, place new demands on the GLAs. It then introduces results from a feasibility
study of EO data gathered from around GLA waters and summarises the potential benefits for AtoN service
providers.
RÉSUMÉ
Le Groupement des phares du Royaume-Uni et d’Irlande (GLAs) le le Centre spatial national britannique
collabore, au travers de l’initiative du gouvernement du Royaume-Uni Information du secteur spatial, pour
déterminer si les techniques d’observation de la terre peuvent être utilisées pour surveiller les fonds marins
dynamiques.
Les premiers travaux montrent que l’imagerie radar synthétique peut servir à montrer l’emplacement et la
forme des bancs de sable et est disponible sous toutes les conditions météos, y compris la nuit. Les
objectifs de cette évaluation sont la possibilité d’identifier un changement intervenu sur un banc, détecter
les modifications de sa morphologie, et les effets que peuvent avoir ces changements sur les bancs de
sable environnants à proximité des voies navigables. Le résultat de l’évaluation montrera si l’examen des
données d’observation terrestre pourrait être un outil rentable qui permettrait de réduire la surveillance insitu par bateaux.
Nous allons montrer comment l’accroissement de la plaisance, la prolifération des navires à grande vitesse
et les changements dans les schémas de trafic génèrent de nouvelles demandes que doivent satisfaire les
GLAs. Nous présenterons ensuite les résultats d’une étude de faisabilité sur les données d’observation
terrestre glanées dans différentes eaux couvertes par les GLAs et résumerons leurs bénéfices potentiels
pour les fournisseurs de signalisation maritime.
1.
INTRODUCTION
The General Lighthouse Authorities of the United Kingdom and Ireland (GLAs) comprise of The
Corporation of Trinity House, The Commissioners of Irish Lights and the Northern Lighthouse Board. The
GLAs between them have the statutory responsibility to provide marine Aids-to-Navigation (AtoNs) around
the coast of England, Wales, the Channel Islands and Gibraltar, Ireland (as a single entity) and Scotland
and the Isle of Man respectively.
The GLAs support a single research Directorate, Research and Radionavigation (R&RNAV), to work on
research, development, strategic and operational projects. The GLAs employ a wide range of navigational
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 125 aids to ensure that the mariner is kept safe. Current aids include lighthouses, buoys, racons, Differential
Global Navigation Satellite Systems (DGNSS), enhanced Loran (eLoran), the Automatic Identification
System (AIS) and many more. The tri-GLA R&RNAV Directorate play a pivotal role in the development of
these technologies.
The British National Space Centre (BNSC) and the GLAs are in partnership, through the UK Government
Information From the Space Sector (GIFTSS) initiative, with a sub-contractor. The BNSC GIFTSS initiative
aims are to encourage more informed and operational usage of space sector products, being driven by the
user’s (e.g. General Lighthouse Authorities) policy needs, with user involvement being a key part. A BNSCsupplied facilitator works with the users to identify areas where space may be helpful. Test project(s) are
run in order to demonstrate/explore concepts and subsequently the user can potentially develop a product
further with appropriate support from BNSC.
2.
MOTIVATION FOR THE PROJECT
More than 95% of the United Kingdom and Ireland’s international trade is carried by sea. The 8623 miles of
coastline within the GLAs' areas of responsibility rank with the most heavily trafficked and hazardous in the
world. The coastlines vary from isolated rocks and the steep Atlantic coastline, to the low lying relatively
featureless coastline of South East England, off which are shifting sandbanks and channels. The tidal
ranges in GLA waters are significant and currents can reach well in excess of four knots in a number of
places, for example Portland Bill has tides of 6 knots. As a result, the UK has some of the most dynamic
seabed areas in Europe, especially around the Thames Estuary and North Sea coast (GLA, December
2007). The present behaviour of these areas, including trends in shoal movement over long time scales, is
well understood by the GLAs due to many years of maritime experience and survey data. Highly dynamic
channels (including some of the adjacent shoals) are regularly surveyed by the GLAs. Cost-effective
methods taking advantage of advances in technology to aid AtoN positioning are of great interest to the
GLAs due to a potential reduction in the frequency of surveys and associated costs.
The GLAs and BNSC have commissioned a Test Project to determine if satellite observation; in particular,
Earth Observation (EO) techniques, can be used to monitor highly dynamic shoal environments. It is hoped
that information primarily derived from Synthetic Aperture Radar (SAR) systems will be used to detect
changes in the surface expression (captured in an image) of changes in shoal morphology, for example
shoal location, shape, contour and edges.
3.
NAVIGATION REQUIREMENTS
The GLAs share three principles that underpin their Marine Aids-to-Navigation (AtoN) service provision:
•
the GLAs must provide such aids to navigation as deemed practicable, necessary and justified by
the volume of traffic and the degree of risk;
•
to obtain the greatest possible uniformity in AtoN, each GLA shall take into account appropriate
international directives, requirements, recommendations and guidelines, including those of the
International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA); and
•
the GLAs co-operate closely to minimise overlap in the provision of AtoN and to ensure consistent
levels of service provision (GLA, February 2007).
The GLAs’ Navigation Policy is “to determine that the AtoN provided by the GLAs in the interest of general
navigation and local AtoN provided by Local Lighthouse Authorities, Harbour Authorities and Offshore
Operators, meet the requirements of the present and changing needs of all mariners and that AtoN comply
with internationally accepted standards (GLA, December 2007)”. The GLAs currently use a range of
information and data, when determining if an AtoNs should be re-positioned.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 126 Figure 15: Survey data from a Hydrographic survey, overlaid on an Admiralty Chart. Figure 16 : Contour lines extracted from a Hydrographic survey, overlaid on an Admiralty Chart. Geographic Information System (GIS) software is used to aid the process. The grid of the required
coordinate system is loaded into the GIS software on top of a UK map and the necessary charts are then
loaded for the area of interest. Finally, any processed survey data (Figure 1) or contour lines extracted from
survey data (Figure 2) can then be loaded in the GIS software as the top layer.
Survey data (e.g. from harbour authorities, UK Hydrographic Office (UKHO) or the GLAs) are compared
with previous and current buoys positions. This along with in-depth maritime knowledge is used to
determine if an AtoN should be re-positioned. Hydrographic information for locating AtoN is safety critical
and must identify the shallowest depth rather than the average depth in a location. AtoNs, especially buoys,
are positioned within a margin of safety which will keep shipping away from dangerous shoals. The
information discussed above is also used when deciding on the frequency of surveying an area.
The use of EO data is seen as a potential indicator of change to optimise the operational scheduling of in
situ bathymetric sounding programmes. Further EO data sets could then be brought in as an additional
indicative layer, into the GIS software and therefore subsequent decision-taking processes.
The GLA requirements for this project are:
•
to identify if a change in a shoal has occurred;
•
whether a change has been manifested as a bulk lateral movement of the shoal, a change in the
morphology of the shoal, or both;
•
to identify where the sediment (sand/mud/ shingle) has moved to;
•
whether there has been any influence on surrounding shoals, and;
•
the detection of new shoals being created.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 127 Instead of satellite imagery itself providing a reliable
measure of depths around shoals in UK and Irish waters,
this project requires the use of a sequence of satellite
images (of the surface expressions) to indicate if there
are changes in shoal shape or position. If successful, this
would be verified by in-situ measurements. The aim of
this project is therefore to use satellite imagery to assist
in optimal placement and timing of survey vessel usage.
“The SOLAS Convention Chapter V Regulation 13
requires that contracting governments undertake to
arrange for the establishment and maintenances of such
AtoN as, in their opinion, the volume of traffic justifies
and the degree of risk requires. [Moreover they are]…to
arrange for information in relation to these AtoN to be
made available to all concerned.” (IALA Guideline 1004,
2005). It is anticipated that Earth Observation may aid
the Risk Management process as described in the IALA
Guidelines (Figure 3).
4.
Figure 17 : The Risk Management Process for AtoN authorities (IALA Guideline 1018, December 2008) SATELLITE EARTH OBSERVATION
TECHNIQUES
There are two type of Earth Observation considered for use within the GLA remit, SAR and optical imagery.
SAR can, under favourable conditions, show sea floor topographic features in shallow water areas.
4.1
Synthetic aperture radar
Radar is an active sensor within an Earth Observation satellite, such that it provides its own source of
energy to produce an image. It does not require light (as for some optical systems) and data can be
acquired either by day or by night and in all weather conditions. The use of radar means cloud cover can
be penetrated. Radar transmits and receives pulses in a narrow beam in the cm bands of the
electromagnetic spectrum; the returning echoes are then recorded, taking into consideration their strength,
time interval and phase. The “synthetic aperture” refers to the apparent “larger” size of the radar antenna,
as the radar is mounted on a moving platform. The reflected signals are combined from along the moving
flight path. The aperture, or area used to receive signals, is created artificially during the signal processing.
These techniques give greater image resolution.
The signal received by the SAR antenna from each transmitted radar pulse is directly connected with the
physical characteristics of the target through a backscattering coefficient. The value of this backscatter
coefficient (corresponding to grey values in optical images) is dependent on: surface roughness,
wavelength of the radar and the radar beam incidence angle. For the sea, the surface roughness will
generally depend on wind speed and direction, surface currents and on the presence of nearby shoals.
SAR has, under favourable conditions, the ability to detect sea floor topographic features in shallow water
areas. Such conditions include the presence of a strong current, with small scale waves on the sea surface
to provide the radar backscatter
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 128 Í Figure 18 : Schematic plot showing the relationship between SAR image intensity, sea surface roughness, tidal flow and underwater bottom topography (Alpers et al., 2004). Figure 4, highlights the response of the SAR images
relative to sub-surface features. Water movement near
shoals can give rise to areas of rough or breaking water.
The rough water has a higher radar backscatter than
surrounding calm water and is usually well imaged by
SAR. The pattern of rough water is governed by tidal
stream rate and direction and also by the contour and
shape of nearby shoals. Hence, the SAR image shows a
pattern that is influenced by the topography of the shoal: any changes in the shoal topography could
therefore be expected to be seen as changes in the SAR image.
In practice, it can be difficult to measure depth directly with SAR due to the dynamic processes between
the sea surface and seabed. SAR image intensity variations correspond well to bathymetric features and so
SAR can additionally be used to infer a change in shoal position or topography in shallow water.
4.2
Optical sensors
EO using optical methods employs passive sensors, meaning that (usually) solar irradiance is modified in
the reflection process by the Earth’s surface and then detected by airborne or space-borne sensors. The
physical process for optical remote sensing of the marine environment is as follows: sunlight penetrates
water and is reflected by the bottom or by suspended material in the water column. It is scattered and
attenuated by the progress into and out-of the water column. The attenuation of light by water increases
with the depth of the water column.
Satellite images acquired by optical sensors often show coastal water in a range of different hues, i.e. in
usual processing, darker blue hues for deeper water and bright blue hues for shallow water, or for
reflections from suspended materials above the seabed (Melsheimer et al., 2001). The presence of organic
and inorganic sediments can therefore act as a tracer for identifying water movements and frontal
boundaries. Hence, the movements in such sediments can provide information about the movements of
water around and over a shoal and add correlative information to the assessment processes.
Additionally, thermal band information acquired by airborne and space-borne sensors can provide further
information on the movements of bodies of water with different temperature around shoals, again adding to
the assessments.
5.
AIMS OF THE PROJECT
The aims of the project are to examine whether satellite-borne EO techniques can assist in detecting and
monitoring changes in the location or topography of selected shoals within the coastal waters of the United
Kingdom and the Republic of Ireland. Within this project a shoal is defined to be a landform within a body of
water and typically comprised of sand, silt, pebbles or rocks; it occurs where a stream of water promotes
deposition of such granular material, resulting in a localised shallowing of the water. Changes in water
dynamics are expected to result in the mobility of such granular material.
Additionally, the project aims to establish:
•
the suitability of the techniques developed against potential time / uncertainty limits for GLA operations;
•
to outline a prototype for an operational delivery system;
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 129 •
to establish the potential costs and benefits of
incorporating EO for these purposes into the GLAs’
processes, and;
•
to investigate how inferences may be drawn as to the
highest probability of where the bulk of such
sediment has then been deposited, via a map-based
approach with appropriate indications of assessed
uncertainties.
Currently the project aims to conduct an end-to-end
practical feasibility test and assessment of the value of
the resulting information and not to implement and
deliver a fully operational system.
Figure 19 : ERS‐1 acquired on 30/7/1992 @ 10:52 UTC, corresponding to mid springs flood tide in the Thames Estuary. 6.
RESULTS FROM “DESK” FEASIBILITY STUDY
An initial “desk-based” feasibility study was undertaken as previous research suggested that the
underwater topography of the seabed can be detected in EO SAR sensor images. There has been little
published to show that sequences of SAR images can be used to quantitatively indicate changes in shoal
position, morphology, and with quantified assessments of uncertainties. Prior to this study, it was unknown
which satellite remote sensing method would be most suitable for the GLAs application and whether there
was the availability of data for EO to be a viable method of monitoring shoals within close proximity to
navigable channels. The study examined the use of both optical sensors and SAR for measuring changing
bathymetry, with three measurement methods investigated:
•
Direct measurement of bathymetry through the attenuation of visible light with depth;
•
The inference of changes in bathymetry by observation of related changes in sea surface features (e.g.
wave patterns, breaking waves, tide rips etc.);
•
The inference of changes to bathymetry by observation of sediment transport, e.g. by monitoring the
presence of suspended matter caused by scouring at wind turbine pylons.
Using available EO satellite data, it is possible to measure the fundamental properties of the sea surface
(surface temperature, surface roughness, wave height, the colour of the near-surface layers and the
intensity of reflected light). In order for these shoal-like features to be detected, a measurable “signature” is
needed in at least one of the methods stated earlier.
Satellite imagery from SAR can be used to show the location and, in some cases, the approximate shape
of shoals. SAR images are particularly effective as they can be obtained in all weather conditions and at
night: European Remote Sensing (ERS) SAR satellite images of the Thames Estuary (Figure 5) for
example, show features that indicate the approximate positions of submerged sand banks and shoals.
Figure 5 shows strong intensity variations at the location of the main shoals in the Estuary where depths
change from 20m to 2-3m in a lateral distance of a few hundred metres.
The Holm Channel site (off Great Yarmouth, Norfolk) was investigated in this study in terms of visibility of
shoal-like features in SAR images (in low resolution thumbnails). The SAR coverage was investigated for
the years 2004 and 2005 by accessing the ESA Quick Look on-line archive. It was found that only 1 image
was obtained from the ENVISAT Advanced SAR (ASAR) sensor in Image mode, but there were over 60
wide swath (i.e. 150m spatial resolution) images, where swath refers to the area imaged on the surface.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 130 There was a smaller number of ERS-2 SAR images, 28 and 29 respectively (Table 1). The higher spatial
resolution data for ERS-2 revealed clearer data for the features compared to the “Wide Swath” ENVISAT
ASAR catalogue data. For operational users, there appears to be good archival data coverage upon which
a “change” assessment can be based for the project. In terms of the future availability of SAR data, from
other assessments it seems likely that ongoing acquisition of space-borne SAR data will also be possible.
The GLAs have therefore decided that SAR imagery is timely, and within their remit.
SAR system; Mode
No. of images acquired (‘04)
No. of images acquired (‘05)
ENVISAT ASAR; Image mode
1
1
ENVISAT ASAR; Wide Swath
mode
63
62
ERS-2 SAR; Image Mode
29
28
Table 5 : Available SAR Coverage for the Holm Channel site, for the years 2004 and 2005, from the ESA Satellites, ERS‐
2 and ENVISAT. Í Figure 20 : “Quick‐look” images for ERS‐2 SAR for 2004 and 2005. A factor identified in the “desk-based” study was that there
is a likely link between feature detectability and the rate of
tidal flow or strength of the tidal steam. This was
additionally investigated for the Holm Channel area. It was
noted that here, shoal locations and shape could often be
inferred from SAR images.
Figure 21 : Correlation between tidal stream rate and images with detectable features (ERS‐2 SAR images recorded over the Holm Channel Area).Î No. of images
Turning to a closer investigation of the SAR data: in
many of the ‘quick look’ SAR images of the Norfolk area,
an outline of the shoals was observed, corresponding to
an
approx
4
imate
Visible '04
Visible '05
“V”
Invisible '04
Invisible '05
shape,
which was similar to the shape of the “Scroby Sands”
3
shoal in this area (Figure 6).
2
1
0
0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6
Tidal stream rate (knots)
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 131 There also appeared to be a correlation between the detected visibility of shoal features and increased tidal
flow. Increased likelihood of detectability in the Holm Channel area occurred for tidal stream rates of
greater than 1.6 knots (0.82ms-1).
Figure 7 shows that in 2004, 8 out of 22 images contained shoal-like images, with virtually all these images
recorded with high tidal stream rates. Images where no features were detected occurred over the full range
of tidal stream rates. In 2005, 7 images contained shoal-like features and 5 of these occurred at tidal
stream rates greater than 1.6 knots. Where the tidal steam rates were greater than 2 knots and no features
were seen, shoal visibility may have been affected by additional factors such as wind speed and direction.
Based on the desk feasibility study, if full resolution images (i.e. 30m) are used, and tidal rates are greater
than 1.6 knots, it is expected that 50% of images can be used.
As stated earlier, there are two main methods whereby optical data obtained from space-borne systems
can contribute to clarifying bottom topography. The first method is by assisting in bathymetric monitoring
and determination. The second method is by monitoring suspended sediment flows to indicate constancy
or change in channel dynamics. The regions around the UK coast, unlike say clear waters of the
Mediterranean Sea, are characterised by high turbidity (high sediment concentration) waters and sediment
movements, with therefore significant light attenuation. It is anticipated that in the areas of interest for the
GLAs the quantity of suspended matter is likely to be high due to the proximity of shoal and river outlets. In
extreme conditions (i.e. maximum sun elevation, low wind and current speeds) it may be possible to
perceive changes in bathymetry by using optical sensors to measure depths through the attenuation of light.
Any extraction of quantitative information will require a determination of the attenuation coefficient for these
conditions (using in situ measurements). The “desk feasibility” study concludes that optical techniques will
be of little value for direct measurement of depth in UK and Irish waters.
Í Figure 22 : Optical satellite image showing sediment loads in the Thames Estuary. The second optical method investigated was monitoring
sediment flow dynamics to infer the change or stability in
hydrographic channel structures. The studies showed
that it should be possible to infer some gross changes in
bathymetry by observing the changes in surface
features. Shoals are likely to cause breakers to form,
which will subsequently be detected by optical sensors.
It is unlikely that more subtle changes in wave
roughness, will be visible using optical sensors. A
significant disadvantage of optical systems (particularly
in the UK) is the presence of cloud. Satellite optical
sensors are also unlikely to be able to quantify sediment
concentrations accurately at high sediment loadings
(Figure 8).
The concentration and associated inferred motion of
sediments and water bodies in marine areas are often
resolved by most optical systems currently in space.
This is based on either the various levels of penetration of the blue-green-red parts of the spectrum or from
the changes in the sea surface temperature associated with the mixing at near-shore and off-shore waters.
This “tracer” method is expected to be the most relevant to this project.
It is therefore suggested that the use of such “tracer” information (e.g. sediments, chlorophyll concentration
levels or sea surface temperature) stated above, may contribute to the inferences of water motions around
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 132 shoal, and other features. It is obvious from the study, that care is required to separate any bottom feature
inferences, from those obtained from water-borne sediments and temperature-based inferred movements.
It is anticipated that to separate these effects, imagery under different tidal/water-mass conditions should
be used. Optical and thermal infra-red imagery are seen as complementing data into SAR-based analyses.
Hence, some preliminary conclusions are emerging that will be tested within the practical feasibility study
being undertaken by the GLAs and BNSC under the UK GIFTSS Programme.
These are:
•
The SAR pattern will map the rough water areas, not the shoal itself.
•
For a given site and under similar tide conditions, the shape of the pattern will be influenced by
changes in shoal topography.
•
The detection of such changes between time-separated images will be an indication that some shoal
movement has taken place. This would then need to be examined in detail using on-site surveys.
•
An assessment of uncertainties within the process will be required.
7.
SUMMARY AND CONCLUSIONS
Initially, it seems likely that space-borne SAR data can be used by the GLAs to evaluate and manage risk,
which would enable timely, operational scheduling of survey vessel activities in support of the placement of
marine AtoNs. This is now being investigated by the GLAs and BNSC in a practical feasibility test. This will
include a quantified assessment, with associated uncertainty assessments, from SAR data into operational
planning. Shoal visibility in SAR data seems best when the time of image acquisition corresponds to the
times of high tidal stream rates, with the preliminary findings indicating rates in an excess of 1.6 knots
(0.82ms-1) being optimal.
Some possible benefits include:
•
Improvements to monitoring movements of shoals close to navigable channels;
•
Assessments of potential constrictions on navigation channels and needs for re-alignment of Aids-toNavigation and/or dredging;
•
Wider and more routine monitoring of possible changes in shoals;
•
Inputs to the assessment and impact of wind farm positioning;
•
Contributing to more efficient scheduling of GLA assets
8.
ACKNOWLEDGEMENTS
The framework for this study rested on support from Mr Phil Hart of the UK Department for Transport,
Captain Duncan Glass and the Navigation Directorate of Trinity House. We also acknowledge earlier
contributions from the late Captain Neil Turner of Trinity House.
Admiralty Chart Figures: © Crown Copyright and/or database rights. Reproduced by permission of the
Controller of Her Majesty’s Stationery Office and the United Kingdom Hydrographic Office
(www.ukho.gov.uk)
9.
REFERENCES
Alpers W., Campbell G., Wensink H. & Zhang Q., “SAR Marine User’s Manual, Chapter 10. Underwater
Topography”, NASA, 2004.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 133 The General Lighthouse Authorities of the United Kingdom & Ireland, "2020: The Vision", 2004.
The General Lighthouse Authorities of the United Kingdom and Ireland “Joint Navigation Requirements
Polices”, December 2007.
The General Lighthouse Authorities of the United Kingdom and Ireland, “Radio Navigation Plan”, February
2007.
The General Lighthouse Authorities of the United Kingdom and Ireland, “Aids-to-Navigation Review”, 2005.
International Association of Marine Aids to Navigation and Lighthouse Authorities, “Guideline 1004: Levels
of service”, Edition 1.1, December 2005.
International Association of Marine Aids to Navigation and Lighthouse Authorities, “Guideline 1018: On risk
management”, Edition 2, December 2008.
Melsheimer C. & Liew SC., “Extracting Bathymetry from Multi-temporal SPOT images”, 22nd Asian
Conference on Remote Sensing, 2001
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 134 Experiment and Research on Using Ultra Capacitor as Power of AtoN Aids to Navigation Department of Shanghai China MSA ABSTRACT
As an energy-saving, environment-friendly and durable newly developed energy, Ultra capacitor has been
applied in many fields. But it is still a trial used on aids to navigation. Through this experiment, the
applicability, feasibility and problems could be found and verified, facilitating the coming application and
further research.
keywords ultra capacitor; energy of aids to navigation, environment-friendly
RESUME
En raison de son économie d’énergie, son écologie et son énergie durable, l’Ultra Capacitor est utilisé dans
de nombreux domaines. Mais il est toujours à l’essai dans celui de la signalisation maritime. A travers cette
expérimentation, ses applications, sa faisabilité et les problèmes potentiels ont pu être identifiés et vérifiés,
facilitant ainsi les applications futures et les recherches.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 135 1 BACKGROUND AND AIM
Entering the new century, the energy mostly used on aids to navigation is maintenance-free lead-acid
battery, with advantages of operational convenience, high reliability, small maintenance workload, but also
with disadvantages in the number of charge and discharge times, low efficiency, short lifetime, high
comprehensive maintenance cost. Unexpected malfunctions caused by energy short of battery surface
from time to time. So it’s a tendency to search an alternative energy. Ultra capacitor, a energy-saving,
environment friendly, long lifetime energy, has been used in many fields. Through the experiment of using
ultra capacitor as aids to navigation energy, the applicability, feasibility and problems could be found and
verified, facilitating the coming application and further research.
2 CHARACTERISTIC AND APPLICATION OF ULTRA CAPACITOR
2.1 the working principle and characteristic
Ultra capacitor is a new electrochemistry energy storage device between traditional capacitor and battery.
Its energy density is higher than traditional capacitor, and with a much higher power density and longer
circulation lifetime to battery. The charge and energy are stored by the electric double layer emerged in the
charge separation on the interface between electrode and electrolyte, or by the Faraday pseudo-capacitors
emerged in the oxidization-reduction reaction of the electrode. It has many advantages such as quick
charge, high-current discharge, long circulation lifetime, maintenance free and wide working temperature
range. The characteristic illustrate as follows:
Table 1 characteristic of several energy storage device Traditional
Ultra capacitor
battery
index
capacitor
Charging time
10-6～10-3S
1～5 min
1～5 h
Energy density ,wh/kg
<0.1
1～10
20～200
Power density, w/kg
10000
1000～5000
50～1000
Charge/discharge efficiency，%
≈ 100
>90
70～85
circulation，times
>106
>12000
200～1000
2.2 Classification of ultra capacitor
According to storage mechanism, ultra capacitor can be divided into double-layer capacitor and Faraday
pseudo-capacitors; and it can also be divided into symmetric and asymmetric types depending on whether
the active substance on the positive and negative poles are the same.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 136 2.3 Application condition
Ultra capacitor has been widely used electric vehicle, energy storage devices of solar power and windmill
power generation system, backup power supply in industry and some electronic products.
3 COMPARISON BETWEEN ULTRA CAPACITOR AND LEAD-ACID BATTERY
The existing power system on aids to navigation lantern mostly adopt the mode of solar panels and battery.
The panels charge the battery in the daytime and the battery supply the power to the lantern.
3.1 Main defects of lead-acid battery
After 10 years of application experience, many defects reveals: short usage lifetime(2-3 years, to the most
6-8 years), poor charge acceptance characteristic and low charge/discharge efficiency, not indeed
maintenance free and risk of heavy-metal contamination of lead.
3.2 Main advantages of ultra capacitor
With advantages of quick charge, long usage lifetime, indeed maintenance, ultra capacitor is expected
optimum power on aids to navigation. Table 2 shows the comparison between lead-acid battery and ultra
capacitor:
capability
Lead-acid battery
Ultra capacitor
Specific energy/(Wh/Kg)
20～30
9～10
Charge/discharge efficiency/（％）
70～80
≥95
-25—55
-25—55
cost/ (RMB/Wh)
1.5
20
circulation（100％discharge concentration）/（cycles）
200
12000
Working temperature range/（℃）
3.2.1 Long lifetime
Ultra capacitor can charge/discharge 12000 times, in other words more than 30 years if charge/discharge
once a day. Furthermore, in actual use the ultra capacitor doesn’t work on full load, so its usage time would
be much more than 30 years.
3.2.2 High charge/discharge efficiency
The leak current of ultra capacitor is very low, it can even adopt energy when the solar panels provide a
charge current under 100mA. The charge/discharge can come to 95%.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 137 3.2.3 Indeed maintenance free and environment friendly
In the charge and discharge course, the internal reaction is only ion shift between two polar, no
consumption of electrolyte. So no maintenance is needed and would not result pollution for the use of
environment-friendly electrode material.
3.2.4 Low comprehensive cost
In a 40-year period, ultra capacitor need only one group of new capacitor, but lead-acid battery need 13
groups. So 13 times of maintenance cost is added and the overall cost is much lower.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 138 4 ULTRA CAPACITOR MODULE DESIGN
4.1 lantern parameter
4.1.1 input voltage range:8-28V
4.1.2 energy consumption:4.80Wh/h
4.2solar panel parameter
4.2.1 peak value: 55W
4.2.2 open circuit voltage: 21V
4.2.3 short-circuit current: 2.3A
4.3 technical requirements
The capacitor series can provide sufficient energy for the lantern working 12 hours everyday and lasting 14
days.
4.4 design calculation
4.4.1The storage energy in ultra capacitor: 4.80*12*14 806.4Wh
4.4.2 mono-block needed
We adopted 80000F mono-block (each mono-block capacity is 20Wh when the voltage is between 0.81.8V, and weigh 2.0Kg ), so 40 pieces are needed(806.4/20＝40).
4.4.3 connection between mono-blocks
The lantern works between 8-28V, and the solar panels’ open circuit voltage is 21V, so we can decide the
connection between mono-blocks: every 4 mono-blocks parallel, and then all the paralleled mono-blocks
series. So the ultra capacitor’s voltage is 8-18V, the weight is 85Kg while the volume measures
700*500*260 mm3.
5 EXPERIMENTATION ON AIDS TO NAVIGATION LANTERN
5.1 experiment devices:
5.1.1 ultra capacitor module (type: 10-4-UCE18V80000):
The module contains 40 UCE18V80000 mono-blocks, with the connection of every 4 mono-blocks parallel
and then the paralleled blocks series. The detailed parameters show as follows:
Table 4: parameters of ultra capacitor module parameter
value
Rated voltage range Vmaxw～Vminw， V
8-18
17th IALA Conference 17ème Conférence de l’AISM Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 139 Max voltage Vmax， V
19
Min voltage Vmin, V
7
Storage energy in rated voltage range，kJ
2880
capacity，F
32000
resistance，Ω
0.020
Times of charge/discharge
≥12000
weight，kg
85
dimensions（L×W×H），mm，
700*500*260
Working temperature range，℃
-25/+55
5.1.2 parameters of solar panels
5.1.2.1 peak power: 55W
5.1.2.2 open circuit voltage: 21V
5.1.2.3 short-circuit current: 2.3A
5.1.3 parameters of lantern
5.1.3.1 input voltage range: 8-28V
5.1.3.2 working current(each layer):0.2A(green and white), 0.15A( red and yellow)
5.1.3.3 static working current: ≤5mA
5.1.4 monitoring device type MYGPS-204
5.1.4.1 voltage: 5-28V(DC)
5.1.4.2 power
When emission: 150mA@+12VDC averagely (data can be emitted in 10 seconds in excellent signal
condition, then into normal operation)
In normal operation: 40mA@+12VDC
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 140 5.2 Continuous discharging experiment on lantern
5.2.1 Aim
Through the continuous discharging experimentation without charge, the continuous working days can be
known while during rainy or cloudy days when the solar couldn’t charge the ultra capacitor.
5.2.2 Method
A fully charged ultra capacitor is directly connected to the lantern and then works. The total discharging
time is calculated.
5.2.3 experimentation date
From 2008-4-28 to 2008-5-2.
5.2.4 Results
Working voltage （V）
Continuous discharging time（h）
14-8
104
Note: the reason that initial voltage is 14V but not 18V is we began the experimentation 5 days after the
ultra capacitor was charged and the voltage had fallen.
From the experimentation, we can see that if the lantern works 12 hours a day and the voltage of ultra
capacitor is between 14-8V, the ultra capacitor can provide sufficient energy for 8.7-day continuous working.
And if the initial voltage is 17V,it can work continuously 177hours, that is 14.8 days.( E＝1/2C（V12-V22）,
V1 :initial voltage, V2 : ultimate voltage)
5.3 Experimentation under simulated working condition
5.3.1 Aim
Through the simulation of working condition, the stability of ultra capacity batteries be tested.
5.3.2 Method
The solar panels, lantern, ultra capacitor and monitoring device are connected as actual use. Working
current and voltage of ultra capacitor are monitored and the signal is transmitted by the monitoring device.
13.5
800
13
700
12.5
600
12
500
11.5
400
11
300
10.5
200
10
100
9.5
494. 25
475. 25
456. 25
437. 25
418. 25
399. 25
380. 25
361. 25
342. 25
323. 25
304. 25
285. 25
266. 25
247. 25
228. 25
209. 25
190. 25
171. 25
152. 25
133. 25
95. 25
76. 25
57. 25
114. 25
From diagram 1, we could
38. 25
9
0. 25
0
V）
工
作
电
压
（
14
900
19. 25
5.3.4 Results
Diagram 1 working voltage
and current curve of the
ultra capacitor (May 2008)
超级电容器工作电压和电流曲线（ 2008年 5月）
1000
mA）
工
作
电
流
（
5.3.3 Date
From May 4,2008 to July
28,2008, while only one
solar panel is used during
May 4 and June 27, and 2
solar panels used during
June 27 and July 28.
时间（h）
超级电容器放电电流
超级电容器工作电压
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 141 see that the working voltage is between 13-13.5V, and the discharging current between 500-700mA. A
conclusion could be reached: the ultra capacitor works in good condition and could meet all the
requirements of AtoN lantern.
Diagram 2 working voltage and current curve of the ultra capacitor (June 2008) In diagram 2,the
voltage during June
14
1400
1 and 6 was stable.
13
1200
From June 7 to 18,
12
1000
for the rainy
11
weather, the voltage
800
10
of the ultra
9
600
capacitor
8
descended while
400
7
the current the
200
6
opposite, until the
0
5
night June 18 the
voltage declined
below 8V and the
时间（h）
lantern couldn’t
超级电容器放电电流
超级电容器工作电压
work normally. The
rain lasted to June 27, and in that time the lantern worked intermittently for the solar panels couldn’t charge
the ultra capacitor normally and sufficiently. When the weather got good 27 June, a second solar panel was
added, the voltage rise to normal and the lantern worked well again.
572. 5
550. 5
528. 5
506. 5
484. 5
462. 5
440. 5
418. 5
396. 5
374. 5
352. 5
330. 5
308. 5
286. 5
264. 5
242. 5
220. 5
198. 5
176. 5
154. 5
132. 5
88. 5
110. 5
66. 5
44. 5
0. 5
22. 5
工作电压（V）
工作电流（mA）
超级电容器工作电压和电流曲线（ 2008年 6月）
Diagram 3 working voltage and current curve of the ultra capacitor (July 2008) 超
容器工作
和
2008 年 7 月 ）
流曲 （
1000
14
13.5
900
13
800
mA
）
12.5
700
12
600
11.5
工作 500
流（
11
工作
（
10.5
400
10
300
9.5
200
9
100
0
）
V
8.5
459.5
486.5
513.5
540.5
567.5
594.5
378.5
405.5
432.5
216.5
243.5
270.5
297.5
135.5
162.5
189.5
324.5
351.5
0.5 27.554.581.5108.5
8
（ h）
超
容器放
流
超
容器工作
The capacitor and lantern worked well in all July, and the voltage stabilized during 13-14V while the
discharge current between 500-900mA.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 142 5.3.5 Experiment on light beacon
We set the ultra capacitor(type：10-4UCE18V80000) on Linshui 1 light beacon in
Yangshan for experiment during 28 August
and 10 November.2 solar panels ( total
power:40W) were used during 1 and 26
September while 4 panels( total power: 80W)
used after 27 September.
Diagram 4 shows the voltage curve during experiment on Linshui 1 light‐beacon. In diagram 4, the charging voltage stabilized at 13.5V during 1 and 26 September. And the voltage
increased to 17V after 2 panels added. Even in rainy weather, the voltage ascended to 17V quickly so long
as the sunlight was enough.
5.3.6 Experiment on light-buoy
On 25 December 2008, 2 series of 80000-farad
ultra capacitors were arranged on light-buoy
302 and 304, and 2 series of 120000-farad
ultra capacitor were set on light-buoy 303 and
309. After half a year’s trail, the voltage
remained steady at 18V.
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 143 6 CONCLUSION
6.1 Preliminary conclusion
The experiments had shown high applicability and feasibility on aids to navigation, and could meet the
actual working requirements.
6.2 Existing problems and solutions
6.2.1 On actual working condition, the ultra capacitor could maintain working and provide enough energy
for lanterns for 11 days without charging. But on some extreme conditions, for example continuous rainy
weather lasts for 15-20 days, the ultra capacitor couldn’t ensure the normal operation of the lantern.
6.2.2 Solutions
6.2.2.1 increasing the power of solar panels so the voltage could held at 17-18V ensuring normal
working in extreme weather.
6.2.2.2 increasing the energy capacity of each mono-block and adopting higher-capacity ultra
capacity.
The 2 solutions above-mentioned both could meet the extreme weather condition. The most important
items are reaching balance between the solar panel’s power and ultra capacitor’s capacity, realizing a best
practice of cost and lifetime.
6.2.2.3 Arranging a watertight charging socket on battery box, so we could charge the ultra
capacitor urgently using vessels in extreme weather.
2009-08
17ème Conférence de l’AISM 17th IALA Conference Cape Town, South Africa, 22‐27 March 2010 Le Cap, Afrique du Sud, 22‐27 mars 2010 Session: e‐NAVIGATION AND EMERGING TECHNOLOGIES Session : e‐NAVIGATION ET TECHNOLOGIES EMERGENTES Page 144 proceedingS1.pdf
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PROCEEDINGS
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MARITIME ACCIDENTS AND NEAR MISSES / ACCIDENTS MARITIMES ET “QUASI-ACCIDENTS”
17 Conference of the International
Association of Marine Aids to Navigation and
Lighthouse Authorities (IALA-AISM)
MARITIME ACCIDENTS AND NEAR MISSES
ACCIDENTS MARITIMES ET “QUASI-ACCIDENTS”