Soft mobile robot inspired by animal-like running motion

There is a considerable demand for legged robots with exploring capabilities such as passing through narrow pathways. Soft robots can provide a solution for such applications. Here, we propose a soft legged mobile robot with bimorph piezoelectric main body and pre-curved piezoelectric legs. We experimentally demonstrate the performance of the soft mobile robot. The mobile robot can move 70% of the body length per second. In addition, we investigate physical mechanisms behind the locomotion of the mobile robot using a numerical simulation. Interestingly, the mobile robot generates an animal-like running motion. We find that the amplitude difference of the legs, depending on the leg activation condition, may affect the performance of the robot. We also confirm that the soft mobile robot can maintain the movement under impulsive shock owing to its flexibility.