LA gears up for computer road

Drivers on a stretch of freeway outside the coastal city of San Diego next summer will not speed and if they drive drunk, it may not much matter. For California, fittingly enough, is to be the venue of an experiment that may truly revolutionise the culture of the car.

Engineers broke ground this week for an ambitious practical test of the so-called driverless freeway. By August 1997, it is planned, cars equipped with sensors to pick up signals from magnetic spikes in the roadway will drive by themselves along a 7.8-mile stretch of Interstate 15 - and turn off, hopefully, at the right exit.

"There are going to be complications to work out, but this is the future of transportation," said Lynn Barton, San Diego coordinator for the consortium of government agencies, car companies and private experts involved in the first experiment of its kind in the world.

The car phone has already lowered the blood pressure of drivers stuck in jams on California's roads. Earlier this year Los Angeles' first double- decker freeway opened, with a high-speed car pool lane for environmentally responsible commuters. But the San Diego project conjures a vision of commuters being conveyed rapidly and safely along so-called smart roads while they read the paper or look at the view. Take the driver out of the equation, transport experts say, and you remove the 90 per cent of crashes blamed on human error.

Back in 1991 the United States Congress passed the Intermodal Transportation Act, aimed at developing a viable automated freeway system by 2002, and providing the bulk of $200m (pounds 130m) in financing to do it. Governor Pete Wilson put up $5m in state funding to encourage them to choose a Californian venue. A single lane of Interstate15 will be used, with engineers working at night to bury the three-inch spikes in the asphalt about one yard apart. Cameras and radar units mounted in the cars will enable them to move in close convoys and even avoid road debris.

Crowded freeways display classic characteristics of chaos theory - at a critical density, a single driver slowing causes a ripple effect that can create a tailback miles long. The smart cars, by contrast, would communicate their moves by radio.

The question remains whether passengers will trust their lives to a computer. The cars will stay strictly within the speed limit, Mr Barton said. That may be a disappointment for drivers in the the state, who on the rare occasions when traffic is clear like to put their foot down.

Computers presumably will be programmed to resist road rage, and the urge to lead police officers on 100mph chases. That alone could save lives. Between 1993 and 1995, a record 47 people were killed and nearly 2,000 injured in police pursuits in Southern California.