AGRS Tools and Models

Australian Geospatial Reference System logo

The Australian Geospatial Reference System is managed by the Intergovernmental Committee on Surveying and Mappings’ Permanent Committee on Geodesy.


Tools

Propagation between GDA2020 and ATRF2014

Tool under development.

Transformation from GDA94 to GDA2020

Transform data from GDA94 to GDA2020 using the 7-parameter similarity transformation or grid transformations (including both conformal and conformal plus distortion). The transformations are only valid inside the legal extents of GDA2020.

Australian Vertical Working Surface

The Australian Vertical Working Surface (AVWS) tool is used to transform between GDA2020 ellipsoidal and AWVS heights (with uncertainty). AVWS is a gravity model that provides the offset between the GDA2020 ellipsoid and the Australian quasigeoid. The AVWS model heights can be derived from GNSS, with an accuracy of 4-8 cm, without needing to connect to survey mark infrastructure. The conversions are valid for latitude and longitude coordinates between 8(S) to 61(S) and 93(E) to 174(E).

AUSGeoid

The AUSGeoid tool is used to transform between GDA ellipsoid heights and AHD heights (with uncertainty if using AUSGeoid2020). The AUSGeoid model provides the offset between the GDA ellipsoid and the Australian Height Datum (AHD). With this tool, AHD heights can be derived from GNSS, with an accuracy of 6-12 cm, without needing to connect to survey mark infrastructure. The conversions are only valid onshore in Australia. Please note, only GDA2020 coordinates should be used with AUSGeoid2020.

Vincenty's Formulae (inverse and direct)

Given a coordinate, an ellipsoidal distance, and a geodetic azimuth, use Vincenty's direct formula to calculate the coordinate of a second point. Given two coordinates, use Vincenty's inverse formula to calculate an ellipsoidal distance and a geodetic azimuth between the two points.

Conversion between geographic and grid coordinates

Use Krueger's n-series formulae to project between a latitude and a longitude (geographic coordinates) to an easting, northing, and zone (grid coordinates), and vice versa. Note: Krueger's n-series formulae are more accurate versions of Redfearn's formulae.