On the Improvement of Multi-Legged Locomotion over Difficult Terrains using a Balance Stabilization Method

This paper deals with the real‐time walking of a multi-legged robot over difficult terrains using a balance stabilization method in order to achieve a fast speed and robust locomotion with minimal tracking errors. The stabilization method is described through a ZMP‐based online pattern‐generation scheme inspired by bio‐mimetic stepping leg transferences with an active balance control so as to reduce the propagation of instability while performing rapid stepping actions for a fast walking gait in the presence of external disturbances. The proposed control system uses a force‐position controller [14] which takes impact dynamics into consideration to compensate for the effect of external perturbations during walking by estimating impulsive forces in real‐time. Using the proposed stabilization method, the robot plans appropriate footholds on the ground in order to achieve a reasonable average walking speed over difficult terrains in a natural environment. The success and performance of the proposed method is realized through dynamic simulations and real‐world experiments using a six‐legged hexapod robot.