Engineers in Bristol are to construct a small team of robots which will hunt and catch slugs in arable fields. The project, led by Dr Owen Holland of the Intelligent Autonomous Systems Engineering Laboratory at the University of the West of England, has been awarded a ROPA (Realising Our Potential Award) from the British Department of Trade and Industry.

The aim of the project is to build a self-sustaining system, so it is intended that the predatory robots will return to a base station before they run out of power and discharge their slug cargo into a fermenter, the biogas from which will power a generator from which the robots will recharge their batteries.

Slugs were chosen because they move slowly enough to enable capture. To counter problems of stability over the rough terrain, the robot will probably recognise slugs using sets of tiny video cameras by comparing sequential images: if a slug-sized patch has moved, the robot will extend a long arm to capture the slug.

As well as providing engineers with practical opportunities to develop energy efficient machines, the project should provide a fresh analytical tool to ecologists and behavioural scientists. Unlike natural predators, the robots will not need to move on or switch to alternative food sources if slugs are not active.