Robot moved by a slime mould's fears

A bright yellow slime mould that can grow to several metres in diameter has been put in charge of a scrabbling, six-legged robot.

The Physarum polycephalum slime, which naturally shies away from light, controls the robot's movement so that it too keeps out of light and seeks out dark places in which to hide itself.

Physarum polycephalum is a large single-celled organism that responds to food sources, such as bacteria and fungi, by moving towards and engulfing it. It also moves away from light and favours humid, moist places to inhabit. The mould uses a network of tiny tubes filled with cytoplasm to both sense its environment and decide how to respond to it. Zauner's team decided to harness this simple control mechanism to direct a small six-legged (hexapod) walking bot.

As the slime tried to get away from the light its movement was sensed by the circuit and used to control one of the robot's six legs. The robot then scrabbled away from bright lights as a mechanical embodiment of the mould. Eventually, this type of control could be incorporated into the bot itself rather than used remotely.