LANs Aim to Steer Cars from Traffic Jams
by Chris Oakes

6:11pm 20.May.97.PDT -- More cars would fit on freeways with fewer jams if drivers entering the roads surrendered control to a wireless local area network - a network that would electronically link and commandeer cars while their drivers sat idle.

That's the thinking behind an industry- and government-led effort to automate travel along urban freeways. But auto-safety experts warn that the way cars are corralled in herds will cause new types of traffic hazards.

MPI Inc. and MobilConnect Software are developing a mobile wireless network technology under contract for the Partners for Advanced Transit and Highways program at the University of California. PATH is a "core participant" in the National Automated Highway System Consortium, a group of industry and government organizations formed in response to the Department of Transportation's call for automated roadways.

To steer and manage platoons of as many as 20 cars, UC researchers were looking for a high-speed wireless data link between vehicles and a second, wide-area network of roadside servers. The peer-to-peer, mobile network would center around the progress of a designated lead car in each platoon. That car would feed steering, braking, and velocity data to the platoon's other cars.

"There was no off-the-shelf solution for this problem," said Tom Thorsen, president of MPI. The company worked with Digital Wireless, an Atlanta-based radio and modem maker, to create a spread spectrum network to let vehicles communicate without interference from cars going in the other direction.

Cars compatible with such a system need special gear such as radar for measuring the distance between cars and steering sensors that interact with magnets in the roadway. Detroit is in on the action, with General Motors acting as a "core participant" in the automated highway consortium.

MCSI's "MobilSoft" mobile data communications software runs over MPI's 2.4-GHz, Windows NT-based spread-spectrum wireless network. This network updates platooned cars with travel data 50 times per second.

The second, wide-area network would act as a traffic control system, managing the flow of platoons and feeding them information on upcoming obstacles, delays and highway speeds. These WANs could potentially serve unrelated information to the idle driver, such as email and drive-time entertainment content.

In the automatic control enabled by these inter-vehicle and wide-area networks, the NAHSC sees increased safety, better highway throughput, and - speaking to environmental concerns - reductions in vehicle emissions per kilometer.

One of the biggest tricks of the automated highway will likely be selling the idea to commuters. Anyone who's used a computer knows they can suffer bugs, viruses, hackings and crashes. Will handing a steering wheel over to a network create new traffic hazards? "It does take a little bit of time to get used to it," said Jay Kniffen, principal development engineer for the PATH project. "That's partly why we have a display system interface, so the car tells you what it's doing."

That's not enough to reassure activists such as Clarence Ditlow, executive director of the Washington, DC-based Center for Auto Safety. In AHS systems, Ditlow sees a train wreck. "I suspect that a typical accident would be like a train accident - where the cars fly off in opposite directions" - including, he notes, the direction of oncoming vehicles. "If you want to do trains, make a train - not a train of cars," he said. "What this is really all about is selling more vehicles - by packing more cars into each lane."

To prove the technical feasibility of the system in the real world, a demonstration will be conducted in August in San Diego, on a 7.6-mile stretch of highway.

In the end, an automated highway may not eliminate traffic jams, just stave them off. Peter Calthorpe, author The Next American Metropolis, sees only more sprawl and continued congestion. "This will only be as successful as building new freeways, which basically delays the problem. You get slightly increased efficiency, through which you get more sprawl - and with more sprawl, you get more congestion," he said. Related Wired Links: The Information Superhighway by Joe Wiesenfelder