Chao Ding, Lelai Zhou, Xuewen Rong, Yibin Li, and Jason Gu
Quadruped robot, lateral impact recovery, landing point, vertical height compensation
Maintaining the balance under unexpected lateral impacts is a challenging problem for quadruped robots. When the lateral disturbance is large enough to break the static stability, the quadruped robot needs to take one or more steps sideward to regain balance. During the positive adjustment steps, the programming method of the landing point for the swing feet is proposed in this paper based on the linear inverted pendulum model. With this method, the landing position only relies on the feedback velocity of the trunk and the desired standing height. The trunk velocity is estimated only using the displacement sensors mounted in the standing legs joints. Concerning about the asynchronous landing of the swing feet caused by the attitude oscillation, a compensation approach based on coordinate rotations is introduced to this work. A robot model is built in the simulation environment based on a hydraulic actuated quadruped robot prototype. Simulation results show that, with the analytical velocity feedback gain in this method, the quadruped robot can regain balance though minimum steps while causing the least attitude instability.
Important Links:
Go Back