The march of the kilobots

“A THOUSAND-ROBOT SWARM” sounds like the title of a 1950s science-fiction B movie. It is actually, though, the title (or, strictly, part of the title) of a paper in this week’s Science. Indeed, the paper in question, by Michael Rubenstein of Harvard University and his colleagues, describes what might, in the hands of a film-maker, be an even scarier idea: a swarm whose members can co-ordinate their actions.

To be precise, Dr Rubenstein’s ’bot swarm (above) has 1,024 members (2¹⁰ being a conveniently binary number), known apparently without irony as kilobots. Each is a rigid-legged tripod that moves around by vibrating. Kilobots communicate with infra-red light, which can reflect off the table Dr Rubenstein uses for his experiments, and are programmed with three types of behaviour.