Robot volleyball. Lego robots during the world's first robot volleyball competition. Five universities entered teams of two autonomous robots for the contest. During the 5 minute games, the ball is rolled across the pitch from team to team, each having 60 seconds to hit it back. The robots were all built with Lego Mindstorms kits, which include infrared communicators, motion sensors and programmable bricks controlling moving parts. Ball-locating ultrasound sensors were also allowed. The larger robot was made by Manchester University. Photographed at the British Association's Festival of Science in Sheffield, England, in September 1999.