Geodetic Survey Modernisation activities

2014 ISV Surveying Expo

Roger Fraser, Geodetic SurveyOffice of Surveyor-General Victoria

Outline

Geodetic Strategy Consultation Draft

New version of SMES

Re-adjustment of Victoria’s GDA94 and AHD survey control networks

Progress towards datum modernisation

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Geodetic Strategy

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Available as a consultation draft

Identifies strategic context, priorities and challenges

Focussed on improving positioning accuracy and reliability

Guided by 2013 Geodetic Infrastructure Questionnaire results

Closing date for feedback is 29 August

Geodetic Strategy

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Geodetic Strategy

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Geodetic Strategy

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Geodetic Strategy

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Total responses: 177

New version of SMES

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New interface with updated VicMap data, Google street view

Revised survey control mark categories and symbols

Flexible search options and several download format options

Online submission of sketch plans and raw survey measurements

New geodetic measurements database

Rigorous network adjustment system for processing of Victoria’s GDA94 coordinates and AHD heights

Open Web Services to support location based services applications

New version of SMES

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maps.land.vic.gov.au/smes

New version of SMES

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Legend Description

SCN Mark. PM with adjusted GDA94 coordinates, no AHD height

SCN Mark. PCM with adjusted GDA94 coordinates, no AHD height

SCN Mark. PM with estimated GDA94 coordinates, levelled AHD height

Non-SCN Mark. PM or PCM with estimated GDA94 coordinates, no AHD height

Non-SCN Mark. PM or PCM with estimated GDA94 coordinates, estimated AHD height

SCN Mark. PM with adjusted GDA94 coordinates, levelled AHD height

SCN Mark. PM with adjusted GDA94 coordinates, estimated AHD height

Defective PM or PCM

maps.land.vic.gov.au/smes

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maps.land.vic.gov.au/smes

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maps.land.vic.gov.au/smes

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maps.land.vic.gov.au/smes

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maps.land.vic.gov.au/smes

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2014 Victorian Adjustments

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Victoria’s GDA94 and AHD networks re-adjusted.

New constraints

GDA94 adjustment fully integrated with GPSnet

AHD adjustment aligned with AUSGeoid09

Rigorous uncertainties

Automated process within SMES

2014 Victorian GDA94 Re-adjustment

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Uncertainty Percentage0.050 89% 0.025 64% 0.02 50% 0.01 12%

2014 Victorian GDA94 Re-adjustment

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Correction Percentage0.050 97% 0.025 81% 0.02 44% 0.01 10%

2014 Victorian AHD71 Re-adjustment

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Uncertainty Percentage0.050 91% 0.025 60% 0.02 48% 0.01 7%

GDA94 - initial establishment

20 GDA94 constraintsGDA94 constraints

GDA94 – Present foundation

21 Present constraintsPresent constraints

Progress towards datum modernisation

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Revised constraints (AuScope and GNSS CORS)

National geodetic networks assembled

Reprocessing of all old GNSS data

Rigorous adjustment software run on ANU supercomputer

Research into best approach for handling deformation and uncertainty

Business plan and communication strategy

Progress towards datum modernisation

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1994 2000 2010 2020

GDA94Established

Continuously realised

2012Update

National re-adjustment2015

Victorian re-adjustment2014

Divergence of GDA94 from ITRF (metres) 7cm per year

GDA94Adopted

0 0.4 1.1 1.4 1.8

ITRF velocity model

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Progress towards datum modernisation

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New datum based on 2020 epoch (1.8m difference)

Continuously realised frame, and a static realisation

New tools and procedures

Stakeholder consultations being run to identify issues, implications and best transition approach

ICSM PCG and OSGV to provide leadership and assistance to surveying and spatial information stakeholders

Geodetic Survey Modernisation activities

2014 ISV Surveying Expo

Roger Fraser, Geodetic SurveyOffice of Surveyor-General Victoria