前後揺動に基づく準受動歩行ロボットの高効率歩容生成と運動解析

抄録

This paper presents a robot walking control method that we call quasi-passive dynamic walking. The method is targeted at underactuated legged robots and applied to obtain energy-efficient limit cycle gait on level ground. To achieve efficient locomotion, as well as overcome the underactuation of the system, there are two key points of this method to positively utilize the passive dynamics of the system. The first one is to initialize the walker at the fix Poincaré section obtained from passive dynamic walking on a gentle downhill. The second one is to indirectly excite the hip angle by periodically oscillating a wobbling mass, which is attached to the body frame. The walker is, therefore, able to step forward on level ground without any torque actuation. Moreover, the phase diagram of the generated gait is entrained to limit cycle by the periodic oscillation of the wobbling mass. Our control method enables underactuated legged robots to walk extremely efficiently on level ground with only one actuator, which provides the easiness for implementation on real machines.