Dynamic Walking Locomotion Framework Based on Impulse Force Design and ZMP Principle

Walking gait has the strongest obstacle climbing ability for quadruped robot. The traditional static walking gait plans the ZMP trajectory only, which is low motion efficiency, slow speed and poor anti-disturbance performance. At present, force control is the core of balance locomotion method for quadruped robot, which can improve the adaptive ability of the robot to external forces and environmental disturbances during walking. However, the dynamic walking based on open-loop phase sequence can not guarantee the ZMP constrains all the time. Meanwhile, the center of mass needs to locate in the support area to ensure not falling in walking. In order to solve those problems, a dynamic walking framework combining ZMP phase sequence constraint and impulse feed-forward design is proposed in this paper. Firstly, a ZMP stability principle is introduced to gait phase planning. At the same time, the impulse force planning is used to control the inclination during swing. Combined with the ZMP trajectory planning, the robot motion efficiency has improved. Finally, through the experiments with simulation and physical platform, the proposed algorithm is test on stair climbing mission, and the results verify that the proposed framework has a stable dynamic walking performance.