Development of One-legged Robot with Structural Joint Stops

Human and animal joints have range-of-motion limits. Our research group has realized dynamic motions by a golf swing robot and a humanoid robot by utilizing nonlinear reaction forces generated at both ends of the range of motion. In this study, we developed a one-legged robot consisting of a hip joint and a knee joint with a joint stop mechanism at each joint that utilizes both ends of each joint's range of motion, and established the dynamic model of the robot including the joint stop mechanism. The simulation results to verify the mechanism's effectiveness show that a more stable landing motion can be obtained by using the reaction torque generated by the mechanism. The landing motion experiment was also performed by the robot prototype with the mechanism mounted.