Coordinated Allocation of Driving Forces for Bioinspired Robot with One-DOF Jumping Leg on Rough Terrain

Abstract

Bioinspired jumping robots need to be able to move on rough terrain. Despite the high rigidity and low control difficulty of robots with one-DOF jumping legs, they are more prone to losing stability than robots with multi-DOF series legs due to the varying attitudes of bilateral jumping legs in the initial state, thereby further causing motion failure. For keeping the jumping stability of robots with one-DOF jumping legs, a coordinated allocation method of driving forces is proposed in this paper. On the basis of an analysis of the instability of a locust in the take-off phase, kinematics and dynamics models were established for a robot with active and passive driving modes, respectively. Unlike active driving, passive driving means that the driving forces cannot be adjusted in real time during the take-off phase, and the randomness of the terrain needs to be considered. With the forces of the bilateral jumping legs to the trunk, take-off velocity, and take-off time of the equivalent center of mass as target values, the difference of target values on both sides should be approximately equal. Results show that with the driving forces obtained by the method proposed in this paper as the input, the effect of the rough terrain on the trunk is reduced, and the robot has good jumping stability. This study provides a theoretical basis for the application of jumping robots in complex environments.