AUSTRALIAN LOCAL TIE SURVEYS

27 May 2004 PLAN OF PRESENTATION Stromlo Network Design Monument Design Calibration Targets Instrumentation and Methodology Survey-to-Survey Consistency GPS Stability Survey Report Format MINICO and Calibration Stability See also the BIG ORANGE POSTER

27 May 2004 STROMLO LOCAL TIES

27 May 2004 SLR, DIMM, NEW MONUMENT & NORTH PIER

27 May 2004 FIDUCIAL MONUMENT & MASSIVE BASE

27 May 2004 FIDUCIAL & GLONASS CONE

27 May 2004 SURVEY PLATE ATOP FIDUCIAL

27 May 2004 NEW GPS MONUMENT & MASSIVE BASS

27 May 2004 TOP OF NEW MONUMENT

27 May 2004 GA MONUMENT DESIGN

27 May 2004 GA MONUMENT – TOP DETAIL

27 May 2004 NORTH PIER WITH GPS & CAL TARGET

27 May 2004 SITES SURVEYED BY GA EVERY TWO YEARS (where possible) Yarragadee (SLR/GPS/DORIS/GLONASS/Absolute- Gravity); Mount Stromlo (SLR/GPS/ DORIS/GLONASS); Orroral (SLR now obsolete, was 27km from Tidbinbilla); Hobart (VLBI/GPS/Absolute-Gravity); Tidbinbilla. (VLBI/GPS); Darwin (GPS/GLONASS); Davis, Antarctica (GPS/GLONASS/Tide-Gauge). ALSO: GPS to tide gauge connections throughout the South Pacific including stations at Samoa, Cook Islands, Fiji, Tuvalu, Tonga, Manus Island, PNG, Kiribati, Vanuatu, Nauru and Micronesia

27 May 2004 PLANNING AND STRATEGIES Be timed for optimum survey observations, i.e. timing the survey when weather conditions are neutral to minimise atmospheric effects; Allow for several days down time, particularly on Satellite Laser Ranging (SLR) or Very Long Baseline Interferometry (VLBI) systems; Be planned to avoid critical tracking campaigns; Plan the placement of marks on the telescope/antenna to optimise observations for the determination of axes (in the case of indirect reference point determination), i.e. optimise the target trajectories and the radius of the trajectories; and Place instrument stand-points to satisfy survey accuracy demands (as determined by network simulation if necessary). Forced centring is used to eliminate the introduction of setup errors wherever possible. A Leica Zenith Nadir precise optical plummet is used for all tripod setups, to ensure near zero plumbing errors. Additionally, wherever possible concrete pillars are used for instrument standpoints. This ensures setup stability during the often long observation periods when observations are taken to the antenna or telescope systems.

27 May 2004 EQUIPMENT & CALIBRATION Leica TCA 2003 Total Station Angular Precision (lab. calibrated) 0.”6 Distance Precision (lab.calibrated) 0.5mm + 0.4ppm Annually compared with standard baseline traceable to Aust’n National Standards Leica precision prisms with tribrach and carriers incl. plate bubble Annually calibrated over standard baseline, plus GPS Zenith nadir plummet for centring tripods Fixed height prism pole for Total Station levelling Invar staff for instrument heighting, calibrated biennially.

27 May 2004 MONUMENTATION AND NETWORK DESIGN Ideally instrument standpoints are stable bedrock anchored pillars; Pillars should have reference marks to monitor local deformation; and Survey marks should have an unambiguous reference point. ARP DORIS GPS

27 May 2004 INVARIANT POINT DETERMINATION

27 May 2004 RMS of IVP RESIDIALS: PRIMARY (Az or X) AXIS

27 May 2004 RMS OF IVP RESIDUALS SECONDARY (EL or Y) AXIS

27 May 2004 RMS MINIMUM DISTANCE BETWEEN AXES

27 May 2004 REPEATABILITY, SURVEY-TO-SURVEY

27 May YEARS OF GPS DIFFERENCES, NORTH PIER TO FIDUCIAL MONUMENT Y grid spacing is 1 mm

27 May 2004 THE AUSTRALIAN SURVEY REPORT FORMAT Survey database To ensure the long term archiving and storage of the survey results all report information is stored in the National Geodetic DataBase (NGDB), which is a Windows  relational database of geodetic positions and associated information. All survey are stored with the following information: Earth-centred Cartesian coordinates Latitude, Longitude & ellipsoidal height automatically computed Reference frame & epoch Referenced to source of positions (SINEX file) Exact mark descriptions Images & diagrams The NGDB allows the automatic generation of technical reports that are fully user definable. Survey marks at each observatory are linked to facilitate easy report extraction. Report distribution All Geoscience Australia survey reports are deposited on the Geoscience Australia web site located at SINEX format results files are deposited on the Geoscience Australia ftp server, located at ftp.ga.gov.au/sgac/sinex/ties.

27 May 2004 STROMLO ~ weekly 4-GROUND TARGET ‘MINICO ’ STABILITY, Jan-Jun 2005

27 May 2004 CALIBRATION VALUES, May – July 2005 From NICT Daily Reports