3D Quasi-Passive Walker of Bipedal Robot with Flat Feet Gait Analysis of 3D Quasi-Passive Walking

In this paper, we analysis gaits of 3D quasi-passive walker with flat feet driven by an antagonistic pneumatic artificial muscle. Many bipedal robots have been proposed to realize the high energy efficiency walking. The passive dynamic walking does not require control input. Generally, a foot shape of passive dynamic walking robot is an arc foot. It is intended to establish a control method and walking mechanism to achieve energy efficient and stable gait. Therefore, we developed 3D quasi-passive walker with flat feet. An antagonistic mechanism is constituted by a pair of McKibben muscle. And an antagonistic pneumatic system is used as joint actuators of linkage mechanisms which control the torque, joint stiffness and position simultaneously. This paper shows that the 3D quasi-passive walking in the level ground can realize by the simple swinging (sine) input of the frontal direction, and the stride of the robot is proportional to lateral-plane input. Finally, we examine the structure of an ankle, the control method of an antagonistic pneumatic system and these gaits analysis using COP (Center Of Pressure) and ROS (Roll-Over Shapes).