ZMP COMPLIANT GAIT GENERATION STRATEGIES FOR SEVEN-MASS BIPED ROBOTS

Abstract

This paper presents a simple computational technique to generate ZMP compliant gait trajectories for seven-mass biped robots with no torso. The generation of such ZMP compliant trajectories for one- and three-mass approximations of biped robots have been developed earlier and presented elsewhere. In a one-mass case, the hip is assumed to move according to a self-compensating pattern. In a three-mass case, the swinging foot has been made to perform the prescribed motion and rest of the body is used as the compensating motion. In this work, it is reasoned that such simple techniques are not applicable for seven-mass representation, due to the complexity of the structure. One needs to make realistic approximations without losing model relevance. It is suggested that by sensibly ganging the motion of primitive limb elements, an effective solution can be facilitated. With simple iterative computations, ZMP compliant body trajectories are obtained. Patterns generated by this method agree with earlier solutions obtained by others.