Untethered Soft Crawling Robots Driven by Magnetic Anisotropy

We herein present a soft crawling robot based on the design of the magnetic anisotropic actuation to realize untethered crawling movements. With the self-assembled iron filing mesh tuned magnetically and sealed in silicone rubber matrix, we are able to fabricate a large quantity of crawling robots in parallel by a molding process. The magnetic anisotropy is established in the body of the robot to induce the magnetic actuation. Under an alternating magnetic field near the resonant frequency of the robot, the legs of the robot can bend and release repeatedly to achieve a forward moving velocity of ~0.19 cm/s at 2.5 Hz and 46 mT. In addition, the soft crawling robot is robust enough such that even crushed by a 1.8-ton automobile, it can still be fully functional. We envision the magnetic soft robot design and working principle can be further studied for the advancements of micro-robotics research.