Passive trajectory control of the lateral motion in bipedal walking

This paper proposes passive trajectory control (PTC), a new control method of Acrobot, and discusses its application to biped walking robots. PTC makes the first joint passive and makes the point contact between the whole robot system and the ground, then actuates other joints according to the motion of the passive joint. Due to this interlock, the whole robot system becomes autonomous and the controller is independent of time. Hence, PTC makes it possible to design the robot motion based on not the trajectory of time, but the dynamics around the contact point. In this paper, we design the lateral motion of bipedal walking by means of PTC and realize the dynamic stable motion.