Whole-Body Pace Gait Control Based on Centroidal Dynamics of a Quadruped Robot

Abstract

This paper studies the full-body motion generation of a quadruped robot for pace gait. A motion planning algorithm is designed based on the centroidal dynamics of the robot. The motion planning algorithm generates both position and force reference trajectories. These reference trajectories serve as a guide for the swing motion of feet during the swing phase, while they also serve as a guide for the ground contact forces during the stance phase. A hybrid force-motion control framework is constructed using the operational space formulation (OSF) in order to track generated reference trajectories. We contribute further to the OSF of floating-base robots by decoupling the dynamics of the right and left leg pairs to facilitate pace gait. The proposed motion generation method for pace gait is validated using a full-dynamics simulation environment. The results reveal the competence of the proposed whole-body pace gait control for a quadruped robot.