High-speed biped gait generation based on asymmetrization of impact posture using telescopic legs

The author has proposed a novel method for generating a dynamic gait based on anterior-posterior asymmetric impact posture tilting the robot´s center of mass forward. The primary purpose of this method is to asymmetrize the impact posture by actuating the robot´s telescopic-legs to make overcoming the potential barrier at mid-stance easy, and the mechanical energy is accordingly restored. We have already validated our method through numerical investigations of a planar rimless wheel model with telescopic legs. The results implied that the robot motion becomes remarkably high-speed and the need of ankle brake was indicated. This paper then extends the method to a planar telescopic-legged biped model incorporating the brake effect of ankle spring, and numerically investigate the gait properties. We also discuss the role of anterior-posterior asymmetric shape of human foot from the viewpoint of zero moment point.