The most accurate coordinate transformation system ever created for Great Britain is being unveiled by national mapmaker, Ordnance Survey, at the World of Geomatics and Surveying Exhibition at Donington Park on 8-9 May.
Civil engineers, land and hydrographic surveyors, field data collectors and earth scientists should be about to find their work a little easier as the new transformation doubles the accuracy of the current system.
The agency is launching the improved free-of-charge transformation service – which links Global Positioning System (GPS) coordinates to Britain’s map system, the OSGB36 national grid – on its GPS web site at https://www.gps.gov.uk/
The move should please professionals all over Britain who need to relate their GPS derived position to the same location on a map.
“Two years ago, we launched a transformation on the GPS web site that linked together our national grid references and GPS coordinates. Called OSTN97, it was a major technological advance of its time and managed to achieve a good fit – accurate to within 20 centimetres (68 per cent).” explains Ordnance Survey Director of Data Collection and Management, Neil Ackroyd.
“Ordnance Survey’s new and definitive transformation – OSTN02 – doubles that accuracy to within 10 centimetres (68 per cent), making a significant difference to those needing a high degree of precision in their work.”
A new geoid model that will convert GPS height coordinates to Ordnance Survey heights – to an accuracy of a few centimetres – will also be launched at World of Geomatics & Surveying.
“We developed this new model – called OSGM02 – in conjunction with both Ordnance Survey Ireland and Ordnance Survey Northern Ireland,” says Mr Ackroyd. “It produces a massive leap forward in quality when relating GPS derived heights to local datums. In fact the accuracy across mainland Great Britain is now 2cm (68 per cent).”
Visitors to the show can see presentations about how the two free-of-charge transformation systems work. They can also see demonstrations of the versatility of OS MasterMap – the most definitive, accessible and intelligent large-scale mapping ever produced by Ordnance Survey.