Design of a Felid-like Humanoid Foot for Stability Enhancement

Abstract

The foot is an important part of humanoid robot locomotion that can help with shock absorption while making contact with the ground. The mechanism of the foot directly affects walking stability. A novel foot mechanism inspired by the toes of felids is proposed. The foot has four bionic modules with soft pads and sharp claws installed at the four corners of a flat foot. This foot can reduce the impact experienced during foot landing and increase the time that the foot is in contact with the ground, which can improve the adaptability of the robot to different ground surface conditions with different levels of stiffness. The main structure of the bionic module is a four-bar linkage consisting of a slide way and a spring. Furthermore, the length of the four-bar linkage and the posture of the claw during insertion into soft ground are optimized to improve the stability and buffering performance. The validity of the proposed foot mechanism has been proved in simulations.

Design of an actuator with bionic claw hook–suction cup hybrid structure for soft robot

“…In the relaxed state, the elastic ligaments retract the claws towards one side of the toe bones. When the muscles contract, the muscles and ligaments drive skeletal extension, causing the claws to extend [20]. The attachment mechanism of a cat's claw hook and foot pad demonstrates adaptation to the environment.…”