613
1
INTRODUCTION
The main commonly discussed features of maritime
transport are usually its safety and effectiveness.
Amongthemtheshipssafetyissuesarecrucialfrom
the operational point of view and they can be
considered as one of the most prospective technical
affairs. One ofthe most critical features of seagoing
ships
relatedtohersafetyistheirstability.
Thee‐NavigationconceptoftheIMOasdefinedin
(MSC 85/26/Add.1/Annex 21, IMO, 2009) has
providedtheimpetustoa rangeofresearchprojects
focusing on the utilisation and integration of new
solutions in ship–shore communication and
informationexchangeandprovidenovel
solutionsto
thechallengesfacingtheindustrytoday.
The ACCessibility for Shipping, Efficiency
Advantages and Sustainability (ACCSEAS) project
aims to advance maritime access in the North Sea
region by developing intuitive tools to enable the
seafarers to make safe and effective navigational
decisions. The areas of shipping congestion and
limitationsare
identified;inaddition,novelsolutions
are developed, prototyped and demonstrated in e‐
Navigation test beds in the North Sea region. The
aimsarea.o.toharmoniseMaritimeinformationand
Potentials of e-Navigation
–
Enhanced Support for
Collision Avoidance
M.Baldauf
WorldMaritimeUniversity,MaRiSaResearchGroup,Malmö,Sweden
InstituteofInnovativeShip‐SimulationandMaritimeSystems(ISSIMS),Germany
K.Benedict&C.Krüger
UniversityofAppliedSciences‐Technology,BusinessandDesign,Dept.ofMaritimeStudiesWarnemuende‐ISSIMS
Germany
ABSTRACT:Thee‐NavigationinitiativeofIMOandIALAhasstimulatedandinspireda numberofambitious
researchprojectsandtechnologicaldevelopmentsinthemaritimefield.Theglobaltransportationofgoodsis
notonlyfacingrapidlygrowingshipdimensionsbutalsoincreasingindustrialoffshoreactivities,changingthe
relationbetweenthe
needofareasforsafeandreliablevesseltrafficanditsavailability.Offshoreactivitiesis
increasinglylimitingtheavailablenavigablespacesandconcentratingtrafficflows,especiallyincoastalwaters
andportapproaches.
Enhancedtechnicalsystemsandequipmentwithnumerousaddedfunctionalitiesareinuseandunderfurther
development providing
new opportunities for traffic surveillance and interaction. Integrated Bridge and
NavigationSystemsonboardmodernshipsnotonlysupportthebridgeteamsandpilotsonboard,butalso
allow for more comprehensive shore‐based traffic monitoring and even allow for re‐thinking of existing
regimesandproceduresontrafficmanagement.
A
sophisticatedmanoeuvringsupporttoolusingfastreal‐timesimulationtechnologyanditsapplicationforon
boardsupportas well as for itspotential integrationintoenhancedshore‐basedmonitoringprocesseswhen
linkedwiththe‘MaritimeCloud’ willbeintroduced.Thepotential for contribution togenerateharmonized
collision warnings will be
discussed and explained. This paper is a reviewed and extended version of
(Baldauf,Benedict&Gluch,2014).
http://www.transnav.eu
the International Journal
on Marine Navigation
and Safety of Sea Transportation
Volume 8
Number 4
December 2014
DOI:10.12716/1001.08.04.18
614
its exchange and in addition address training
provision to support the real‐world implementation
ofthesolutions(Williams,2014).
ACCSEASworksintandemwiththemuchlarger
MONALISA project that worked to develop
Motorways of the Sea with ecologically efficient e‐
Navigation solutions supportive of EU strategy for
theBaltic
Searegion.Theprojectlaidthegroundwork
for future international deployment of innovative
solutions. The follow‐up MONALISA 2.0 seeks to
develop the concept further by implementation of
measuresinlinewithEUtransportpolicies.
Supportive of the vision of the e‐Navigation
conceptisthesocalledʹMaritimeCloudʹ
whichcould
beutilisedtopopulatepertinentdataandinformation
related e.g. to the ship domain (particularly
manoeuvring characteristics beside length, breadth,
draft,trimetc.); Voyage relateddetails(voyageplan
comprising waypoints, speed and course etc.) and
environmental/hydro‐meteorological information
(wind, sea state, waves, visibility etc.). The
information can be utilised
both on‐board the ship
domainandbyanyshorebasedcontrolcentrelikea
VTS for information sharing and effective decision‐
making. The security and integrity of information
wouldneedtobeaddressed;however,theʹMaritime
Cloudʹ can perform integral service for the
implementation and achievement of future e‐
Navigationservices.
2
PRESENTSITUATION
Beside the introduction of new technologies for
sustainable shipping with reduced emissions, the
growingofdimensionsofcruiseshipsandcontainer
vesselsare characterizing the present situation. Ship
sizesrangefromacarryingcapacityof500‐800TEUs
in the 1950s to todayʹsʹCSCL Globeʹ andʹTriple E
ʹ
typeswithcapacities of over 18,000 TEU. According
tostatementsofDNV‐GLtheyhavealreadyplanned
containershipswithacapacityof22.000upto24.000
TEUwithalengthof430mandbreadthof60m.On
the one hand are the increasing ship sizes that defy
imagination, while
on the other we have ever
increasing levels of offshore activity for oil
exploration, drilling, installation of wind farms,
Floating Production Storage and Offloading (FPSO)
units, oil rigs and platforms etc. There is lack of
harmonisation in the exclusion zones surrounding
suchinstallationswhichcanrangefromasmuchas10
milesto500m.Marineexclusionzonesaresetupand
Particularly Sensitive Sea Areas (PSSA) are
designated. The advancement of fishing activity
further offshore also leads to the restriction of the
navigablespaceavailabletoseafarers.
Finally, the present situation is further
compounded by a shortage of officers. The
current
andfutureavailabilityofseniorofficersisalsoacause
forconcern(BIMCO‐ISF,2010).Anotheraspecttobe
noted is, casualty statistics in shipping. Of the total
number of accidents in 2013, 75% took place in 10
world regions, of which nearly 46% were related to
Europeanwaters(AGCS,
2014).
Figure1:Snapshot of VesselTrafficinthe North Seaarea,
showingAIS‐basedindicationoftrafficsituationin2012as
well as prognosticated traffic figures for 2020+. Coloured
areas indicating established and planned wind mill farm
areas – clearly showing that they will impact present
shippingroutes(takenfrom(Williams,
2014))
The introduction of new and enhanced
information and communication technologies is
accompanying all these ongoing developments to
allow efficient and sustainable operation of ships of
all sizes and provide sufficient prerequisites for the
safety of global sea transportation. e‐Navigation the
completetransportationprocessfocussingnotonlyon
thesituationonboard
butalsoonshorehastoplaya
crucialroleinmitigatingrisk,particularlyincollision
andgroundingaccidentsneartheshore.
3
IMPROVEDTECHNOLOGICALSOLUTIONS
ANDNEWSERVICESASENHANCEDRISK
CONTROLOPTION
IMO has agreed and approved in a number of
documents how to proceed with the further
development of the e‐Navigation activities. For
instance, overarching e‐Navigation architecture is
provided;thereisaproposedwayhowtodevelopa
Common
MaritimeData Structure (CMDS);using of
theIHOʹsS‐100standardasthebaseline.Furthermore
there is an endorsed preliminary list of prioritized
potential e‐Navigation solutions namely improved,
harmonized and user‐friendly bridge design (S1);
means for standardized and automated reporting
(S2); improved reliability, resilience and integrity of
bridge equipment and navigation information (S3);
integrationandpresentationofavailableinformation
in graphical displays received via communication
equipment(S4)andimprovedcommunicationofthe
VTSserviceportfolio(S9).Finally IMOidentifiedon
basisofaformalassessmentanumberofriskcontrol
options (RCO), which were found being most
effective
for risk reduction purposes. These options
are:
RCO1:Integrationofnavigationinformationand
equipment including improved software quality
assurance
RCO2:Bridgealertmanagement
RCO 3: Standardized mode(s) for navigation
equipment
615
RCO 4: Automated and standardized ship‐shore
reporting
RCO 5: Improved reliability and resilience of
onboardPNTsystems
RCO6:Improvedshore‐basedservices
RCO 7: Bridge and workstation layout
standardization
Furtherguidancethatshouldbetakenintoaccount
for research work and technological development is
summarized in IMOʹs strategic implementation plan
finalized by its correspondence group on e‐
Navigation.
Inordertoaddresstheseactivitiesandcontribute
to the further materialization of the
e‐Navigation
strategy,simulationtrialswereconductedtotestthe
efficacy of innovative e‐Navigation solutions as risk
control options. As e.g., two pertinent functions
relatedtotheship‐portinterface–‘shorebasedroute
suggestion’ and ‘display of intended route’ were
tested in simulation trials and are mentioned here
exemplarily. Five different scenarios were designed
andtested twice overthecourseoffourconsecutive
days. At any one time, two bridge teams on
simulation bridges participated in the simulation
runs.Thebridgesweremannedbyexperiencedpilots
as well as mariners and shore based support was
provided by personnel from
the Humber VTS. The
bridge teams changed after two days after
participating in all five scenarios. In a scenario
pertaining to the approach to Humber, the VTS
operator said that prior to the establishment of the
Traffic Separation Scheme (TSS), vessels would
approachfromalldirectionslike
“beestoahoneypot”
andwoulddepart
“likeastarburst”.TheVTSoperator
further went on to note that the functionality that
enablesthemtoseetheintendedrouteofvesselswas
extremelyvaluabletothemas,basedupontheroute,
theycould suggestasuitableapproach to the TSS if
required. The Humber personnel added that they
would miss
the functionality upon their return to
England.Averysimilarresponsewasreceivedfrom
Danish Pilots referring to their area of operation
(Skagen).
4
ENHANCEDCOLLISIONAVOIDANCEUSING
FASTTIMESIMULATIONANDDYNAMIC
PREDICTIONS
Beside the studied route exchange functions
mentioned above, investigations into improvement
for collision avoidance taking into account both the
aspects onboard and shore‐based assistance are
ongoing. Conventional shore‐based services, as
providedintheframeofarecognizedVTSare
based
ontrafficdatacollectedandanalysedinshore‐based
centres. Operators interact with the traffic from a
shore‐based centre by sending out information,
warningoradviceonaregularbasis,ondemandor
when deemed necessary according to the operators’
judgement and in accordance with established rules
and
procedures. In rare cases, e.g. when VTS
operators have detected a certain danger requiring
immediateactiontheymayevensendoutinstructions
to vessels involved in such situations. The essential
mean for exchange of information is VHF
communication.
However, the rapid technological developments
under the e‐Navigation initiative will significantly
change
the landscapeand the status quo of existing
regimes of shore‐based service provision. New
information and communication technology (ICT)
allowscollectionofextensivedatawhichisexpected
tobemorereliableandcanprovidealmostreal‐time
information.Voyage Data Recorders (VDR) and AIS
werefirstoptionstocollect
andprovidemoredataon
the actual situation on‐board SOLAS ships than
information from only the radar and VHF. Today
shipping companies seek to establish company fleet
operation centres (FOC) ashore. VDR manufacturers
have developed sophisticated solutions for data
collection far beyond the minimum performance
standardofVDRsandeven
providedataexchangeto
company owned FOCs via enhanced satellite data
communication links, including even actual rudder,
engineand thrusterdataas well asorderedsteering
values. Presently there is on‐going research work
makinguseofsuchdatafordynamicpathpredictions
for on‐board decision making and shore‐
based
monitoring(e.g.Baldaufet.al.,2012).
For onboard decision making the technology of
fast time simulation can be applied for the
introductionofmoreuser‐friendlyalarmlevelsbasing
on dynamic shipʹs safety zones. IMOʹs Performance
standards for Integrated Navigation Systems
(MSC.252(83) were developed on the basis of
a
comprehensive task analysis and has provided the
essential navigational tasks that needs to be
supported by an INS. Two of which are collision
avoidanceandanotheressentialisalertmanagement.
Fasttimesimulation(FTS)isatechnologyusinga
mathematical model of a certain process and its
influencingfactors
to estimate the future status of a
system faster than in real time. While real time
simulation is e.g. especially used for training
purposestheFTSisspecifically usedforoperational
tasks and to support decision making (Benedict &
Kirchhoff et. al., 2014). For the purposes of ship
navigationFTS can
beusedforthepredictionof the
shipʹspathtakingintoaccounttheimmediatereaction
on control settings (rudder, thrusters, engine etc.).
Differentlyto staticpredictionsase.g. the vectors in
ARPA radar, dynamic path predictions are taking
into account e.g. inertial forces and moments in
relation to actual
environmental conditions (wind,
currentsbut alsowaterdepthetc.). Thereliabilityof
thepredictionsismainlydependentonthevalidityof
the used model and the reliability of input data
mainlyprovidedbysensors.Shipnavigationprovides
a number of use cases for FTS technology. FTS and
dynamic path prediction can
support onboard
decisionmakingwhenmanoeuvringashipincoastal
watersorevenwhenberthinginharbours.However
it can also be used to enhance situation assessment
with respect to existing risks of collision or
grounding. The application of sophisticated
algorithms providing predictions for a complete
rangeofmanoeuvringoptions
canbeusedtoqualify
thetriggeringofwarningsandalarmsforbridgealert
management(RCO2).
616
Steering Parameter
• Rudder angle,
• Engine revolution / power
• Bow-/Aft-thru sters
•…
Status Parameter
• max available rudder angle,
• Time for rudder command
• max engine revolution /
power
• Time for reverse engine
manoeuvre
•…
Actual moving
parameter
• course, speed (x, y)
• ROT, headin g, draft,
• Lateral wind area
•…
Actual environmental
condition
• Wind (force, direction),
• Depth of water
• Course of fairway
• Aids to Navigation
• targets
VDR based
manoeuvring
Data base
• Manoeuvring data
depending on
• Loading
condition s
• Environmental
condition s
• Steering and
Control
parameters
• Steering and
control
condition s
•…
Fast-time
Simulation
Calculation of:
• Response time
according to
manoeuvring
parameters of
the actual
conditions
• Safe passing
distance
according to type
of situation and
sea area
Application and
Display of
adapted
CPA-, TCPA-
thresholds
for situation-
dependent
Collision alerts
CAUTION,
WARNING,
ALARM
Figure2: Generic Outline of an onboard Manoeuvring
SupportSystemapplyingFast‐Time‐Simulation‐Technology
for triggering collision warnings according to IMO
standards
Figure3: Operational (manoeuvring) limits of a ship
visualizedasdynamicpathpredictiononbasisoffasttime
simulationtechnologyandimplementedinanECDIS‐based
manoeuvring support tool for purposes of situation
assessmentregardingriskofcollisionormonitoringofsafe
and efficient conduction of manoeuvres for purposes of
onboard
assistanceoftheOOWandtosupportmonitoring
dutiesofanshore‐basedoperatoraswell
Inglobaltermsalertmanagementshallcontribute
to the harmonization of priorities and to the
classificationofalerts.Itistoenhancetheirhandling,
distribution and presentation to the OOW. IMO has
definedthreelevelsofalerts–firstisʹCautionʹ(lowest
level;asakindofasignalthatthere
isasituationwith
certain deviation from usual (safe) conditions)
secondlyʹWarningʹ(requiringimmediateattentionof
thebridgeteam)andfinally,highestlevelofanalert
ʹAlarmʹ (requiring immediate action to avoid any
dangeroussituation.
InrespecttothetaskofʹCollisionAvoidanceʹthere
is similarity to the different stages
of an encounter
situation with risk of collision. Cockcroft and
Lameijer suggested and discussed those stages in
(Cockcroft & Lameijer, 2012) in respect to the
obligations of a stand‐on vessel in case of an
encounter situation of two engine driven vessels on
crossingcoursesaccordingtorule17.From
thisbasic
discussion,amore detailed and sophisticated model
for situation assessment has been derived (Hilgert,
Baldauf,1997).Thismodeltakesintoaccountfurther
rules of COLREGs for other types of encounter
situations under conditions of good and restricted
visibility. This enhanced model concentrates on
recommendationsforactiontobetaken
derivedfrom
COLREGs but also provides suggestions for the
quantification of limit values for the situation
dependentsafepassingdistancesasaCPAthreshold
aswellasforTCPAlimitswhentotakethoseactions.
Table1.Recommendationforlowerlimitofownshipsafety
zone (CPA‐threshold) [dimension given as ship length of
largestshipinvolvedintheencountersituation]
_______________________________________________
Encountersituationgood restricted
visibility visibility
_______________________________________________
head‐onsituationmeeting2,55
port/port‐side
Overtaking2,55
head‐onsituationmeeting510
port/port‐side
Crossingsituation510
_______________________________________________
Table2. Applied simplified risk model for target alert
prioritization
_______________________________________________
alert limitvaluesincaseCPA>CPA‐Limit
forgeneratinganalert
_______________________________________________
Caution Manoeuvreinampletime<RNGObservation
Range(e.g.12..16min)
Warning LowerManoeuvringLimitRNGManoeuvre
inampletime(e.g.6min)
Alarm RNG<LowerManoeuvringLimit(timefora
coursechangeof90°usingHardrudderacc.to
actualconditions)
_______________________________________________
Taking into account the prevailing circumstances
ofaspecificsituationwhichneedstobecharacterized
e.g. by input from sensor data about the
environmental conditions (visibility, wind, sea state)
aswell as ship status (including thedimensions but
moreover especially taking into account the actual
manoeuvringcharacteristicsoftheinvolvedvessels)
it
ispossibletoalsoharmonizethesituation‐dependent
definitionofsafetyzonesaroundashipand,incase
of a potential violation of it, to prioritize collision
alerts into the given levelsʹcautionʹ,ʹwarningʹ and
ʹalarmʹ by ranking the level of risk of concerned
targetsinrespectto
theremainingtimetotakeaction
to avoid a collision. In this way targets with risk of
collision can be marked i.e. green (caution), yellow
(warning) and red (alarm). Of course green level
needs not necessarily to be visualized in the AR
environment. However, the yellow level should be
implemented
andconfiguredandswitchedonatthe
OOWʹs intentions. The red level alarm should be a
fixed audible alarm which should not be able to be
switchedoff.
For this purpose the proven TCAS concept, used
for collision avoidance in aviation, has been
transferredandadaptedby(Baldauf,Benedictet.
al.,
2011).InTCAS,amongothers,asocalledʹResolution
Advisoryʹ, requiring the pilot to follow a climb or
descentinstructionisimplementedinTCASasaʹlast
line of defenceʹ. Applying this concept to collision
avoidanceinopensea,forinstanceatarget,violating
the safety zone
of the own ship should generate a
collisionʹalarmʹ and be marked red, when it comes
close to the lower manoeuvring limit, at which the
ownshipbyitsownmanoeuvrealoneisabletoavoid
a collision. This manoeuvre can be determined by
using dynamic prediction using FTS of own
617
manoeuvring capabilities for the shipʹs evasive
manoeuvre (Baldauf & Benedict et. al., 2012). This
meansincasethestandonvesselfindherselfsoclose
to a give way vessel that a collision can only be
avoidedbyherownmanoeuvrealone(determinedby
fast time simulation‐based dynamic
prediction of a
coursechangemanoeuvre)than,finally,theredmark
shouldappearintheaugmentedrealityaddedbyan
audible alarm, to indicate and initiate necessary
actionsbytheOOWaccordingly.
The potential for improvement of shore‐based
supportiswellrecognized.Itisespeciallycruiseand
containershipping
companiesthatarealready using
those enhanced capabilities and are aware of the
potential of virtual online monitoring and decision
support. This furthermore already includes route
monitoring, keeping a certain corridor, not only a
simple cross‐track error but also considering actual
shipstatusaswellasweatherforecastsandsea
state
data. Consequently the corridor is no longer the
centre line of the corridor but the corridor is more
enhancedbyconsideringthedriftingtoacertainside.
Theaddedshore‐basedmonitoringactsasakind
of an additional safety barrier and moreover allows
for optimization of the operational
regimes of the
company fleet. Taking those enhanced monitoring
opportunitiesintoaccount it seems that the existing
services offered by VTS could also be improved
accordingly.ComparedtoaVTSoperator
5
CONCLUSION
TechnologicaldevelopmentsintheframeoftheIMOʹs
e‐Navigation initiative allows for substantial
improvement of regarding the support of the
navigator onboard and operators monitoring traffic
from a shore‐based centre. The functionality of
dynamic path prediction using fast‐time‐simulation
technology can be utilised for calculating the
operationallimitsofmanoeuvringtakingintoaccount
theprevailingcircumstancesoftheenvironmentand
theshipsstatusandthatareneededforharmonized
decisionmakingandcoordinatedcollisionavoidance
procedures.
Applicationsforonboardusewillallowforamore
precise estimation of the last time to take action to
avoid
acollision.Fortheimplementationofenhanced
applicationinshore‐basedmonitoringfacilitiesopens
for a much more detailed surveillance of a shipʹs
routeandpotentialrisks.
However, in relation to any enhanced future e‐
Navigation services, it is to be noted that the legal
aspectsofsuchserviceswould
needtobeaddressed
aswellasthetrainingrequirementsfromthepointof
viewofinvolvedstakeholders.
ACKNOWLEDGMENTS
Some of the results and parts of the investigations
presented in this paper are presently performed
undertheEuropeanInterregIVb‐project–ACCSEAS
AccessibilityforShipping,EfficiencyAdvantagesand
Sustainability
and from the European FP 7 project
MUNIN–MaritimeNavigationThroughIntelligence
inNetworks).
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