2017 – Positioning

The year saw significant projects in Positioning, and an important collaboration with Geoscience Australia (GA) and RMIT University.

Positioning

This year saw the completion of two significant projects in the Positioning Program: together they revolutionised how 3D spatial information was collected and managed. The Earth’s crust is far from stable. The Australian Plate has one of the highest rates of tectonic drift in the world, at 7cm per year. New Zealand spans the boundary between two tectonic plates making earthquake activity a common and sometimes devastating reality. All this movement means coordinates that define location, change over time.

Until recently, this reality could often be ignored. But with the emergence of high accuracy, absolute positioning techniques such as Precise Point Positioning (PPP) and its derivatives, incompatibilities between measurement systems and locally defined geodetic reference frames became evident. In this context, the CRCSI worked with partners to design and implement a time-variable frame of reference – otherwise known as a dynamic datum.

Our research developed the technical solutions and software tools to enable the realisation of this new datum. In parallel, the need to transform GNSS-derived height information into a meaningful and practical frame of reference drove a second project to develop a new geoid model for Australia and, for the first time, to augment that model with uncertainty estimates allowing users to better understand the accuracy of the transformed heights and their fitness for purpose.

Both projects placed the CRCSI’s work at the forefront of international research and helped to equip partners for the new era of time-variable location information.