5/8. The Great Robot Race. There's$2 million at stake, as 20 robot cars race across the Nevada desert. With no drivers or remote controls, the cars are on their own. Horizon follows the engineers' successes and failures as they develop the vehicles. If any complete the course, they will have solved many of the most difficult problems in robotics. Producer Mickey Lachman ; Editor Andrew Cohen
www.bbc.co.uk/horizon Machine Men is at 11.20pm