It looked like something out of a science fiction movie when the first U.S. test of "driver-disengaged transit" occurred last August just north of San Diego. There, along a 7.6 mile stretch of highway closed to midday traffic, drivers simply took their hands off the wheel, removed their feet from the pedals, and cruised along -- guided by a combination of technologies that kept them within designated lanes, at a specified speed, and at a safe distance from other vehicles and obstacles. As their cars moved along the "intelligent" highway, people read the newspaper or did paperwork, but not one of them crashed, broke down, or were involved in one of the 6.5 million highway accidents that occur in the United States each year.

The recent demonstration, conducted by the National Automated Highway System Consortium (NAHSC), was the latest step toward a goal mandated in the 1991 Intermodal Surface Transportation Efficiency Act (ISTEA). The goal is to get automated highways in use by the general public by 2020, and NAHSC -- a working group of state and federal government agencies, private industry and academia -- has taken the lead in making that a reality.

What's An AHS

Automated highway systems, when launched, are expected to pack as many as three times more cars onto existing roads, sparing the expense of building new roadways while simultaneously decreasing congestion. Dick Bishop, Federal Highway Administration manager for the automated highway system program, said while it now costs between $1 million and $100 million to build a mile of new highway, it would cost less than $10,000 to equip that same mile with automated vehicle technology.

The view from the passenger's perspective inside a vehicle under automated control

Additionally, computer-steered vehicles are expected to eliminate up to 90 percent of the car accidents that occur on U.S. roads. "The solution technology holds is we can make roads safer," said Kyle Nelson, chief information officer at the California Department of Transportation (Caltrans). "Statistics show 90 percent of all accidents are caused by driver error, so anything you can do to give the driver a little more time, alert them they're about to have a collision or have a computer take the controls and assist, is going to save a lot of lives."

NAHSC plans to build special automated vehicle lanes on existing highways. Drivers will then have a choice of whether they want to use the system or not. If they choose to use it, they will enter a special lane that merges them onto the automated system. At that point, the car's technology interacts with the technology on the highway and takes over the driving. The automated vehicles will travel in a closely packed group, allowing them to "draft" quickly along the road, saving fuel at the same time. A driver who wants to get off the highway would enter a "transition" lane, slowly disengage the system and merge off into normal traffic.

NAHSC -- which includes organizations such as the U.S. Department of Transportation, the University of California, Bechtel, Caltrans, General Motors, and Lockheed Martin -- conducted the recent demonstration of the technology that could eventually comprise the $200 million automated system.

NAHSC examined many systems; among them a hybrid system from the American Honda Motor Co. Honda's offering used cameras and radar in rural areas and then switched to under-bumper sensors guided by iron magnets embedded in urban roadways. Another system, from Ohio State University, teamed radar with magnetic strips in the road.

But according to Nelson, the demonstration was more about combining technologies that already exist rather than testing new technologies. "The equipment being used is pretty much off-the-shelf stuff," he said. "What's new are the combinations of different technologies. Some of the vehicles out there were guided by magnets in the pavement, some of them were guided