Transcript Document

Geodetic Survey
Modernisation activities
2014 ISV Surveying Expo
Roger Fraser, Geodetic Survey
Office 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
2
Geodetic Strategy
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
3
Geodetic Strategy
Frequency of use
Daily
Weekly
Rarely
9%
Monthly
9%
Marks used per month
Monthly
Rarely
Daily
39%
51-100
6%
>100
6%
0-5
0-5
20%
6-20
21-50
51-100
>100
Weekly
43%
21-50
27%
Total responses: 217
6-20
41%
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Total responses: 215
Geodetic Strategy
Where do you conduct most surveys for which you use the survey
control mark network?
100%
Total responses: 212
75%
67.0%
50%
37.8%
33.0%
36.4%
32.1%
23.9%
25%
21.1%
23.9%
17.2%
0%
Metropolitan Central
Melbourne Highlands
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Geelong
Region
Gippsland
Great South
Coast
Hume
Loddon
Loddon
Wimmera
Mallee North Mallee South Southern
Mallee
Geodetic Strategy
Number of marks not fit for
purpose
A lot (>20%)
26%
How important is AHD?
Many
(>50%)
5%
Very few
(<10%)
13%
Moderate
important
24%
Some (1025%)
56%
6
Not
important
6%
Very
important
70%
Very few (<10%)
Some (10-25%)
Very important
A lot (>20%)
Many (>50%)
Moderately important
Total responses: 212
Not important
Total responses: 217
Geodetic Strategy
100%
Which maintenance/enhancement activities do you feel the Victorian
government should continue to invest in
85%
Total responses: 177
80%
61%
60%
64%
58%
40%
20%
0%
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Physical network (e.g. more
marks in certain areas, high
stability marks, marker posts, etc)
Victoria's GNSS CORS
infrastructure
GNSS CORS real-time positioning The realisation of GDA94/AHD71
services
(e.g. ongoing upgrades through
management and readjustment)
New version of SMES
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
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New version of SMES
maps.land.vic.gov.au/smes
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New version of SMES
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
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Defective PM or PCM
maps.land.vic.gov.au/smes
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maps.land.vic.gov.au/smes
12
maps.land.vic.gov.au/smes
13
maps.land.vic.gov.au/smes
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maps.land.vic.gov.au/smes
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2014 Victorian Adjustments
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
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2014 Victorian GDA94 Re-adjustment
2D uncertainties (95%)
18000
15580
16000
Uncertainty
0.050
0.025
0.02
0.01
14000
12000
Frequency
10435
10000
Percentage
89%
64%
50%
12%
8000
5820
6000
3669
4000
2345
2000
17
1130
952
649
306
181
29
5
0.200
0.500
1.000
More
0
0.005
0.010
0.020
0.025
0.050
0.075
0.100
Uncertainty
0.150
2014 Victorian GDA94 Re-adjustment
Corrections to previous coordinates
18000
15440
16000
13741
14000
Correction
0.050
0.025
0.02
0.01
Frequency
12000
10000
Percentage
97%
81%
44%
10%
8000
6545
6000
4217
4000
2000
711
153
115
153
17
0.500
1.000
2.500
5.000
0
18
0.010
0.025
0.050
0.100
0.250
Correction
2014 Victorian AHD71 Re-adjustment
1D uncertainties (95%)
12000
8000
Frequency
Uncertainty
0.050
0.025
0.02
0.01
9706
10000
7448
Percentage
91%
60%
48%
7%
6000
4000
3577
2000
1912
1562
321
44
57
0
19
0.005
0.010
0.020
0.025
0.050
Uncertainty
0.075
0.100
0.500
GDA94 - initial establishment
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GDA94 constraints
GDA94 – Present foundation
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Present constraints
Progress towards datum modernisation
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
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Progress towards datum modernisation
National re-adjustment
2015
1994
2000
GDA94
Established
GDA94
Adopted
2010
2020
2012
Update
Continuously
realised
Victorian re-adjustment
2014
Divergence of GDA94 from ITRF (metres)
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0
0.4
7cm per year
1.1
1.4
1.8
ITRF velocity model
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Progress towards datum modernisation
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
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Geodetic Survey
Modernisation activities
2014 ISV Surveying Expo
Roger Fraser, Geodetic Survey
Office of Surveyor-General Victoria