The hardest part of that 250-mile course—which won’t be revealed until 2 hours before the start—is the obstacles. The vehicles will have to drive through or around sand, mud, boulders, ditches, barbed wire, mountains and at least one overpass where onboard global positioning systems won’t work. The vehicles are expected to travel at an average of 25 mph, and to hit 50 mph or more at times. And they have to be capable of swerving or stopping suddenly.

Some vehicles are being designed specially for the race. Others are retrofits of existing vehicles. For example, the vehicle sponsored by the Geophysical Institute of the University of Alaska, is a 1992 Jeep Cherokee with sensors, beefy shock absorbers and a bevy of computers.

Most teams are still in the preliminary planning and testing stages. The next big milestone will come Oct. 14, when the participants must submit technical papers detailing their work to DARPA. A panel will then determine whether the plans conform to the contest rules and are technically feasible.

Most teams are then hoping to have vehicles in operation by the beginning of 2004. All will then begin to gather in Southern California in March for a DARPA symposium and a technical inspection. Two hours before the race, the route will be given to teams for downloading onto the vehicles’ onboard computers, which will then create digital maps.