This will take place this coming weekend (Nov. 3) when the finalists have six hours to go around a 60-mile course, performing a variety of tasks that are significantly more demanding than those required of vehicles during DARPA's past robot races.

The reason fewer challengers reached the final stage than anticipted, said DARPA director Tony Tether, was that not all of the robo-cars were safe enough on the road. During the qualifying events, one competitor after another drove into trouble - some crashed, some made dangerous turns, and some flew off the course entirely.

Among those in the race-off will be Stanford Racing Team (which won the event in 2005); the Ben Franklin Racing Team, from Philadelphia; MIT; Carnegie Mellon University's Tartan Racing team; Team Cornell from Ithaca, N.Y.; Team Oshkosh Truck; and Honeywell/Intelligent Vehicle Solutions.

European companies' involvement fared quite well in the semi-finals, with Team AnnieWay, and team CorOLO through to the finals.

"The (qualifying event) tested the vehicles capability to merge into traffic, navigate four-way intersections, respond to blocked roads, pass on-coming cars on narrow roads, and keeping up with traffic on two- and four-lane roads. In fact, the only major difference between the (qualifiers) and the final event is that other robotic vehicles will be part of the traffic in the final event," Tether said in a statement.