A Rolling Soft Robot Driven by Local Snap-Through Buckling

Previous rolling soft robots have difficulty in balancing the locomotion speed with energy efficiency and have limited terrain adaptability. This work proposes a rolling soft robot driven by local snap-through buckling, which employs the fast response and configuration maintenance of the bistable structure to enhance the locomotion performance of the soft robot. A theory based on bifurcation and the energy principle is established to analyze the rolling mechanism. The influences of loading position and geometric parameters on the rolling performance are investigated and verified experimentally. The soft robot shows good locomotion speed (0.95 body length per second, BL/s) and small energy loss due to the almost unchanged configuration during the rolling process. The soft robot adapts to complex terrains, including a step with the height of 15 mm, a slope with the angle of 18.36°, and a broken bridge with the gap length of 90 mm (0.443 BL). The proposed rolling soft robot not only has good application prospects in land exploration missions and medical applications but also provides inspiration for the development of rolling soft robots.