A key challenge in bioinspired insect-scale running robots is to make them both agile and resilient. In this study, we develop a dielectric elastomer actuated soft robot that mimics inchworms. We use an elastomer to make the soft body, a stretchable dielectric to provide electrostatic actuation of high power density, and multizone actuation to achieve ratcheting locomotion. We fabricate the body, muscles, and feet in a single piece, with no internal open space. The robot runs four times its body length per second and turns at a radius about three times its body length in 0.3 s. The robot survives compression 30,000 times its own weight and survives collision with a rigid surface at a speed of 30 m/s. The robot can climb a slope of 30°. Walking on a horizontal plane, the robot carries a payload four times its own weight. The robot can operate on land, underwater, and in vacuum. The simplicity in design and fabrication will enable the robot to serve as a model system to investigate insect-scale actuation and locomotion, as well as the social behavior of swarms of robots. The robot also provides a platform to integrate wireless charging, mobile communication, and stretchable electronics.
Keywords: bioinspired; dielectric elastomer; ratcheting locomotion; soft robot.