You might expect a robot’s heartbeat to be a metallic ticking. But the pulsing in this video isn’t completely artificial: it’s powered by living material. Created by Peter Walters from the University of the West of England in Bristol, UK, and colleagues, the pump uses the gas released by live yeast to generate pressure and distend a membrane, turning it into an artificial muscle. A valve - activated by electricity produced by a microbial fuel cell - controls the movement of the membrane. It opens to release pressure when the muscle is fully expanded, allowing it to shrink back to its resting state again to begin another cycle.
