Satellites, and more recently, global positioning technologies have allowed for increasingly precise mapping and surveying techniques. Geoscience Australia, the national agency for geoscience research and geospatial information, has several trials underway that could allow utilities to pinpoint the exact locations of their assets.
As part of the Australian Government’s National Positioning Infrastructure (NPI) Capability, Geoscience Australia is leading a trial of a Satellite-Based Augmentation System (SBAS) for the Australasian region.
A SBAS will overcome the current gaps in mobile and radio communications and, when combined with on-ground operational infrastructure and services, will ensure that accurate positioning information can be received anytime and anywhere within Australia and New Zealand.
Geoscience Australia, in partnership with Land Information New Zealand (LINZ), and the Australia and New Zealand Cooperative Research Centre for Spatial Information (CRCSI) are working with more than 30 organisations and businesses from ten industry sectors to test the economic and social benefits of improved positioning technology.
To date, eleven contracts have been signed with participants from a range of industry sectors, including utility, resources, transport, construction, agriculture and spatial.
The accuracy of positioning technologies is becoming increasingly important to the utility industry, with construction workers required to establish the location of any pipelines or cables before starting to excavate.
Asset owners must also submit plans to contractors indicating the presence of infrastructure assets within the vicinity of a project site, which need periodic updating.
The more precise the data that is being captured, the safer and easier it is for workers to locate utility assets and avoid coming into contact with them.
The SBAS trial is being managed by Geoscience Australia, with support from global technology companies GMV, Inmarsat and Lockheed Martin. CRCSI is managing the industry projects which will trial, evaluate and report on the benefits and applications relevant to their sector.
Experimenting with new technologies
The SBAS trial will utilise three technologies, and is being funded by $12 million from the Australian Government and a further $2 million from the New Zealand Government.
Dr Andy Barnicoat, Chief of the Community Safety and Earth Monitoring Division said the three technologies being tested are first generation SBAS, second generation SBAS and Precise Point Positioning.
“The technologies were turned on in June 2017, September 2017 and October 2017 respectively and project trials commenced in November 2017,” Dr Barnicoat said.
First generation SBAS technology improves positioning accuracy to within half a metre. The experimental Precise Point Positioning capability provides positioning accuracies of ten centimetres.
“It is the first time anywhere in the world that second generation SBAS signals have been transmitted. Australia is also the first country in the world to trial Precise Point Positioning corrections integrated into a SBAS service,” Dr Barnicoat said.
“As part of the SBAS trial, satellite positioning accuracy for all Australians will improve from five to ten metres, to within half a metre. Trial participants will have access to accuracies of less than ten centimetres.”
An improvement in positioning accuracy from five to ten metres to within half a metre could have a huge impact when working in areas where buried assets are present.
Any excavation, irrespective of size, has the potential to damage assets located around the work site, leading to service interruptions, delays to the project, costly repairs and in the worst case scenario, injury or death.
The new technologies augment and correct the positioning signals already transmitted to Australia by the United States’ Global Positioning System (GPS) and the European Galileo system, improving accuracy, integrity, continuity and availability.
“Highly accurate positioning technologies are already available in Australia, but they are expensive and only available in specific areas and to niche markets,” Dr Barnicoat said.
“Australia currently relies on the Global Navigation Satellite Systems (GNSS) of other countries, for example GPS. These international systems typically give Australians positioning accuracy of five to ten metres.”
The SBAS trial is Australia’s first exploratory step to joining countries such as the US, Europe, China, Russia, India and Japan, which are already using the first generation SBAS technology on a daily basis.
Ernst and Young have been contracted to conduct an independent evaluation of the economic and social benefits of an SBAS for the Australasian region.
In addition to the SBAS trial, Geoscience Australia is also working on a number of other projects and positioning technologies that will assist in preventing damage and disruption to Australia’s vast power and water networks.
Mapping coordinates also play a role in the location of utility assets, both in hard copy and electronic plans. Many power and water utilities use Geographic Information Systems (GIS) to capture, store, analyse and manage mapping data and associated attributes which are spatially referenced to the earth.
The current Australian datum, the Geocentric Datum of Australia 1994 (GDA94), which contains the coordinate reference points, is now over 20 years old and movement of the Earth’s tectonic plates means that the coordinates are no longer in the correct place.
The Australian continent sits on the fastest moving continental plate in the world, moving in a north-easterly direction at a rate of about seven centimetres a year.
“We have moved approximately 1.8m since the Geocentric Datum of Australia 1994 (GDA94), and as a result Australia’s coordinates are no longer aligned to coordinates observed from Global Navigation Satellites System (GNSS), such as GPS,” Dr Barnicoat said.
“This movement is significant when it comes to the use of applications that rely on accurate satellite positioning such as the emerging intelligent transport sector, mobile location based services (e.g. smartphones), automated mining operations, precision agriculture and surveying where high absolute accuracies are required.”
While it may not sound like much, an inaccuracy of almost two metres could put whole networks of utility infrastructure assets at risk, resulting in compromised safety to workers and the assets themselves.
The implementation of the Geocentric Datum of Australia 2020 (GDA2020) will be the first update to Australia’s coordinate reference frame in over two decades.
“The modernisation of Australia’s coordinate reference frame will help ensure that positioning information observed from global navigation satellites (e.g. GPS) can be easily and accurately aligned to spatial datasets to improve decision making and enable a variety of economic, environmental and social benefits,” Dr Barnicoat said.
“Geoscience Australia and the Intergovernmental Committee on Survey and Mapping are working closely with government agencies and other organisations that generate or manage spatial information to ensure a seamless transition.”