Implementation of WGS84 and GPSfor Marine Navigation

Dr Terry MooreInstitute of Engineering Surveying and Space Geodesy

The University of Nottingham

Implementation of WGS84 and GPSfor Marine Navigation

Dr Terry MooreInstitute of Engineering Surveying and Space Geodesy

The University of Nottingham

The Project ConsortiumThe Project Consortium

• IESSG, The University of Nottingham

• General Lighthouse Authorities– Trinity House Lighthouse Service

– Northern Lighthouse Board

– Commissioners of Irish Lights

• Port of London Authority

• United Kingdom Hydrographic Office

• IESSG, The University of Nottingham

• General Lighthouse Authorities– Trinity House Lighthouse Service

– Northern Lighthouse Board

– Commissioners of Irish Lights

• Port of London Authority

• United Kingdom Hydrographic Office

Project OverviewImplementation of WGS 84Project OverviewImplementation of WGS 84

• WGS 84 for Navigation Charts– UK Hydrographic Office

• Coordination of Port Facilities– Port of London Authority

• Coordination of Aids to Navigation– General Lighthouse Authorities

• WGS 84 as a Vertical Datum– Port of London Authority

• WGS 84 for Navigation Charts– UK Hydrographic Office

• Coordination of Port Facilities– Port of London Authority

• Coordination of Aids to Navigation– General Lighthouse Authorities

• WGS 84 as a Vertical Datum– Port of London Authority

• Precision Navigation– Port of London Authority

• GNSS Systems Integration– Port of London Authority (VTS)

– General Lighthouse Authorities (Loran-C)

• GNSS Integrity Assessment– All Partners

• Precision Navigation– Port of London Authority

• GNSS Systems Integration– Port of London Authority (VTS)

– General Lighthouse Authorities (Loran-C)

• GNSS Integrity Assessment– All Partners

Project OverviewImplementation of GPSProject OverviewImplementation of GPS

Chart Datum TransformationsChart Datum Transformations

• Test areas in UK and Ireland

• Current chart shift parameters show good agreementon average with transformed coordinates

• Variations (up to 20m at long range)

• Agreement between OSTN97and UKHO method better than 2m

• UK and Ireland OK - but what about other regions?

• What if no published datum, or known parameters?

• Test areas in UK and Ireland

• Current chart shift parameters show good agreementon average with transformed coordinates

• Variations (up to 20m at long range)

• Agreement between OSTN97and UKHO method better than 2m

• UK and Ireland OK - but what about other regions?

• What if no published datum, or known parameters?

WGS 84 as Vertical Reference DatumWGS 84 as Vertical Reference Datum

WGS84 ReferencedWGS84 ReferencedSeabedSeabed

WGS84 PositionWGS84 Positionof Vesselof Vessel

UnderkeelUnderkeelClearanceClearance

Ignores Sea, Tides etc..Ignores Sea, Tides etc..

Port of London TrialsPort of London Trials

GPS Antennas

River Thames Trial TrajectoryRiver Thames Trial Trajectory

174000

175000

176000

177000

178000

179000

180000

181000

182000

564000 566000 568000 570000 572000 574000 576000 578000

Easting (m)

Nor

thin

g (m

)

GPS Accuracy EvaluationGPS Accuracy Evaluation

Mean = 3.589 m RMS =5 mm

Height of VesselHeight of Vessel

49.5

50

50.5

51

51.5

52

52.5

53

53.5

222000 222500 223000 223500 224000 224500 225000

Time (s)

Hei

ght (

m)

GPS Heights of Survey BoatGPS Heights of Survey Boat

GPS River LevelGPS River Level

1.2

1.6

2.0

2.4

2.8

3.2

3.6

4.0

4.4

4.8

5.2

5.6

324000 329000 334000 339000 344000 349000 354000 359000 364000 369000

GPS time (second)

Height(m)

RTK GPS

Tide G auge at T ilbury

Pilot Survey of a Typical European PortPilot Survey of a Typical European Port

Aims

• Assess Quality of Existing Coordinates

• Identify Potential Problems

• Define Survey Procedure(s)

• Estimate Effort Required

• Estimate Scale and Cost of WGS84

Implementation

Aims

• Assess Quality of Existing Coordinates

• Identify Potential Problems

• Define Survey Procedure(s)

• Estimate Effort Required

• Estimate Scale and Cost of WGS84

Implementation

Port of London AuthorityPort of London Authority

River Thames

UK National GPS Network COGRUK National GPS Network COGR

Port of London VTS RadarPort of London VTS Radar

Pilot SurveyPilot Survey

SurveyedWGS84

Coordinates

SurveyedWGS84

Coordinates

TransformedNew CoordsTransformedNew Coords

PublishedVTS Radar

Coordinates

PublishedVTS Radar

Coordinates

OSGBTransformation

Parameters

OSGBOSGBTransformationTransformation

ParametersParameters

CompareCompareCompare

Quality of Existing CoordinatesQuality of Existing Coordinates

00

5050

100100

150150

200200

250250

11 22 33 44 55 66 77 88 99

Radar Site NumberRadar Site Number

Co

ord

. Dif

fere

nce

(m

)C

oo

rd. D

iffe

ren

ce (

m)

Why then no Incidents ?Why then no Incidents ?

80m, 200m, ?

Coordination of Navaids to WGS 84Coordination of Navaids to WGS 84

LighthousesLighthousesLighthousesLighthousesRadionavigationRadionavigationRadionavigationRadionavigation

BuoysBuoysBuoysBuoys

From the Air or at SeaFrom the Air or at SeaFrom the Air or at SeaFrom the Air or at Sea

Implementation of WGS84Coastal Aids to NavigationImplementation of WGS84Coastal Aids to Navigation

Thames EstuaryThames Estuary

Shannon EstuaryShannon Estuary

Sound of MullSound of Mull

1

2

3

Aids to NavigationShannon EstuaryAids to NavigationShannon Estuary

Shannon Estuary Survey ShipShannon Estuary Survey Ship

Classification of Surveyed PointsClassification of Surveyed Points

TypeType NumberNumberLighthouseLighthouse 66

Leading LightLeading Light 44Navigational LightNavigational Light 22

Radar SiteRadar Site 11Tide GaugeTide Gauge 11OSI MarkOSI Mark 77

BuoyBuoy 33OthersOthers 44TotalTotal 2828

ApproachApproach

SurveyedWGS84

Cooridnates

SurveyedWGS84

CooridnatesTransformed

to Chart CoordsTransformed

to Chart CoordsChart

CoordinatesChart

Coordinates

7 parameter OSITransformation(0.5m Accuracy)

7 parameter OSI7 parameter OSITransformationTransformation(0.5m Accuracy)(0.5m Accuracy)

CompareCompareCompare

Lights and LighthousesLights and Lighthouses

00

2020

4040

6060

8080

11 22 33 44 55 66 77 88 99 1010 1111 1212

Co

ord

inat

e E

rro

r (m

)C

oo

rdin

ate

Err

or

(m)

Reference NumberReference Number

BuoysBuoys

-50-50

00

5050

100100

150150

200200

Letter PointLetter Point Beal BarBeal Bar DoonahaDoonaha

Co

ord

inat

e E

rro

r (m

)C

oo

rdin

ate

Err

or

(m)

VTS RadarVTS Radar

945m !945m !

Brown’s Castle B’Bunnion LandmarkBrown’s Castle B’Bunnion Landmark

6534m !6534m !

However,However,

Inp

ut

Rubbish InRubbish In

Ou

tpu

t

Rubbish OutRubbish Out

Transformation

?

?

Size of the TaskSize of the Task

• Lighthouses

– THLS 67

– NLB 196

– CIL 80

• Buoys

– THLS 413

– NLB 185

– CIL 147

• Lighthouses

– THLS 67

– NLB 196

– CIL 80

• Buoys

– THLS 413

– NLB 185

– CIL 147

343

743

The Broad Financial ImplicationsThe Broad Financial Implications

Fixed Aids to NavigationRequirement 10cm AccuracyApproach Static GPS positioningProduction 5 points per day (average)Resources 2+1 staff, plus equip & mobility

Floating Aids to NavigationRequirement 10m AccuracyApproach DGPS positioningProduction 10 points per day (average)Resources 2+1 staff, plus equip & mobility

Fixed Aids to Navigation Fixed Aids to NavigationRequirementRequirement 10cm10cm Accuracy AccuracyApproachApproach Static GPS positioningStatic GPS positioningProductionProduction 5 points5 points per day (average) per day (average)ResourcesResources 2+12+1 staff, plus equip & staff, plus equip & mobilitymobility

Floating Aids to NavigationFloating Aids to NavigationRequirementRequirement 10m10m Accuracy AccuracyApproachApproach DGPS positioningDGPS positioningProductionProduction 10 points10 points per day (average) per day (average)ResourcesResources 2+1 staff, plus equip & 2+1 staff, plus equip & mobilitymobility

A Recommended Approach : NavaidsA Recommended Approach : Navaids

1) Re-Position All Fixed Facilities

2) Re-Position all Critical Floating Aids to Navigation

3) Transform Coordinates of Non-Critical AtoN

Provided the transformation is extensible

4) Verify Coordinates of Non-Critical AtoN

Preferably during routine operations

1) Re-Position All Fixed Facilities

2) Re-Position all Critical Floating Aids to Navigation

3) Transform Coordinates of Non-Critical AtoN

Provided the transformation is extensible

4) Verify Coordinates of Non-Critical AtoN

Preferably during routine operations