Summary
A passive dynamic walker can walk down a shallow slope without any actuation. If the dynamics of the biped is effectively utilized to realize passive walking, the robot walks with energy-less locomotion. An antagonistic pair of pneumatic actuators is one candidate to realize such quasi-passive walking using both passive and active motions like some animals do. This paper presents a simple control of to enlarge the stability of biped walking utilizing passive dynamics. First, we introduce the design of the biped robot used for experiments with antagonistic pairs of pneumatic actuators. Then, we propose to regulate opening duration of the valves based on the observed walking cycle. Finally, experimental results are shown to demonstrate the effectiveness of the proposed control scheme.