Abstract: Limbless crawling on land requires breaking symmetry of the friction with the ground and exploiting an actuation mechanism to generate propulsive forces. Here, we introduced kirigami cuts into a soft magnetic sheet that allowed to achieve effective crawling of untethered soft robots upon application of a rotating magnetic field. We achieved bidirectional locomotion under clockwise and counterclockwise rotating magnetic fields with distinct locomotion patterns and crawling speed in forward and backward propulsions. We experimentally characterized the crawling and deformation profiles of the robot and combined it with detailed multiphysics numerical simulations to extract locomotion mechanisms in both directions. We showed that by changing the shape of the cuts and orientation of the magnet we can steer the robot, and if combined with translational motion of the magnet, program complex crawling paths. The proposed magnetic kirigami robot offers a simple approach to developing untethered soft robots with programmable motion.
Duhr P., Meier Y.A., Damanpack A., Carpenter J., Studart A.R., Rafsanjani A., Demirörs A.F. (2023) Kirigami makes a soft magnetic sheet crawl, Advanced Science, 10(25), 2301895.
Cover design: Negin Sarbaz Hosseini