A transient state machine is demonstrated by J. Liu and co-workers based on findings on the generation, collision, bouncing, adhesion, or coalescence phenomena of self-powered liquid-metal droplet motors. On page 5253, it is shown that such transformable machines could switch among different working configurations such as single robot, separate moving elements, or a swarm of autonomously running motors. The transient state is reversible, such that tremendous discrete droplet machines injected from a single source could recombine to their original state.

Small,2015