3D CAD Maps UK Underground Infrastructure 2006-03-22Posted by clype in Gizmo.
The maze of pipes and cables that snake beneath the UK's streets are to be mapped in a 2.2 million GBP pilot project.
An intimate knowledge of this tubular underworld is expected to help reduce the number of holes that need to be dug by utilities, and cut traffic jams. Nottingham and Leeds researchers will trial new 3D mapping technologies at half a dozen UK locations.
It is thought there are enough pipes and cables below ground in Britain to stretch to the Moon and back 10 times. Some were laid more than 200 years ago and accurate information on their precise positions is often non-existent or sketchy at best.
Even modern records may be spread across numerous databases, making it very difficult sometimes for a contractor to know what a pneumatic drill might hit when it goes into the ground. There are 30 to 40 incidents each year where workmen are seriously injured because they have accidentally sliced through electricity cables.
'When utilities and highways authorities are digging in the street, they often find things they didn't expect, or don't find the things they were looking for,'
'If we had detailed 3D maps of what was down there, we'd be much more efficient at finding and fixing leaks, and connecting people to services.'
The project, known as 'Vista' (Visualising integrated information on buried assets to reduce streetworks), is largely funded by 'The Department of Trade and Industry'.
It will pull together the current records of pipes, cables and wires — be they held in digital form or on paper — and link them to new surveys undertaken at six trial locations. The 'in situ' observations will use ground-penetrating radar and other sensing technologies to find the precise depth and course of the local tubeworks — to within an accuracy of 50 mm.
The project team hopes to come up with a mapping system that can be rolled out to other parts of the country.
'You can't look at an "Ordnance Survey" map to find out what's under the ground,' explained Mr.Tony Cohn, professor of automated reasoning at Leeds University.
'We will be producing an "underlay" to the "OS", to show you what's down there.
'We'll combine all the historical data from the utilities with the in-street data found with location-sensing technology. 'We want to merge this information dynamically and put it on some kind of handheld unit.'
The project could result in mobile devices or displays in street diggers that would present streetworkers with a 3D picture of the pipe and cable layout in front of them. This would give workers the confidence to dig without the fear of accidentally cracking a water main or causing a major gas leak.
One of the major challenges facing the researchers will be in developing the centimetre-accurate, satellite-based location technology they will need to make their street observations. The Global Position System ('GPS') is far from reliable in high-rise urban areas or, indeed, in very leafy locations.
'What we're doing is integrating GPS with other technologies, such as inertial navigation sensors and devices called pseudolites and locatalites (which are ground-based satellites, in effect); and survey equipment that measures angles and distances — to give us the accuracy we need,'
— explained Mr.Gethin Roberts from Nottingham University. However, future streetworkers will not need such complicated location-finding equipment to make sense of their 3D maps. It is expected Europe's newsatellite navigation ('sat-nav') system, called 'Galileo', will greatly enhance the 'GPS' performance once it comes on line towards the decade's end.
Although the 'Vista' project is being led by Leeds in collaboration with Nottingham, there is support from other universities and 19 utility, transport and engineering organisations. 'Vista' links in with another project called 'Mapping the Underworld', which is researching improved sensor technologies to find pipes and new ways of tagging them so they never become lost.