A SMA Actuated Earthworm-Like Robot

Inspired by locomotion principle of earworms, a shape memory alloy (SMA) actuated earthworm-like robot is designed and developed in this paper. Four groups of SMA wires as actuator and one spring as accumulator were introduced. The SMA wires and spring play a role in contraction and extension of an earthworm muscle respectively. For temporal position stopping control, two groups of electromagnets were used as setae of earthworm. By SMA wires were driven independently or simultaneity according to defined movement patterns, the all-round movement of the artificial earthworm freely to different directions was realized. A series of experiments on the self-developed robot moving and turning with different actuation frequencies were carried out. The results showed the validity of the locomotion mobility of the SMA actuated earworm-like robot.