If a hi-tech motorway tolling system is ever implemented, its toughest test is likely to be against ageing technology and foreign vehicles, for instance tourists in old cars on holiday in Britain.
They will be driving cars not fitted with systems to communicate with satellites or microwave interrogation computers on motorway gantries. The number plate pattern will be unfamiliar to the monitoring cameras. And they almost certainly will leave the country before the authorities spot them. After that, it will cost more to track them down than they owe in unpaid tolls. Law-abiding drivers (both from Britain and the Continent) will have to shoulder the costs of any miscreants.
The problem lies in the fact that the eight consortia picked by the Government yesterday all intend to use technologies which, to work effectively, must be fitted to every vehicle on the motorway. Seven of the consortia suggest small transmitter/receivers which could be glued to a windscreen. When the vehicle passes a microwave or infra-red transmitter at the side of the road, or on an overhead gantry, the transceiver would beam back the vehicle details. Such systems are already used in a number of places in Britain, such as for "Roadtag", which allows prepaid toll payments on the Severn Bridge. A computer system would then work out how far the vehicle had travelled and bill the owner.
Payment could be immediate: a prepaid "smart card", like a phone card, could be charged up with money at retail outlets and attached to the transceiver. Alternatively, a bill could be sent to the vehicle's owner. The transceivers would cost up to pounds 30 each.
One consortium suggests fitting vehicles with transceivers which would estimate their precise position to within a few metres using the Global Positioning System (GPS), composed of orbiting satellites. The transceiver would then beam their position to roadside beacons, and payment be made by subsequently billing the owner. But individual GPS systems currently cost about pounds 300, and it will take a huge order to bring that price down below pounds 100.
Both systems would have to spot those evading payment. Camera technology can now spot number plates of vehicles almost flawlessly, despite drivers' best efforts to defeat them with plastic coverings and unusual fonts.
But the consortia accept that their systems will be most heavily tested by visitors and occasional users of the system. "It is a question which becomes fairly complex," says John Jarvis, chief executive of RAM Mobile Data, which is bidding in the GPS consortium. "People might have to buy credit and hire systems at entry points to the country." David Carter, of the Siemens Traffic Controls consortium, says. "We would have to put something at each point of entry into the UK."
Spotting drivers who evade the system will also raise privacy issues, says Tony Pratt, technical executive of Peek, in the Tollstar consortium. "There has to be an audit trail of which vehicle was charged, and when. But that means you can't have complete privacy about who is travelling." A toll system is unusual because, unlike speed cameras, it would also monitor law-abiding vehicles' movements, like a poll tax for motorists.Reuse content