Leg stiffness control based on “TEGOTAE” for quadruped locomotion

Abstract

Quadrupeds exhibit adaptive limb coordination to achieve versatile and efficient locomotion. In particular, the leg-trajectory changes in response to locomotion speed. The goal of this study is to reproduce this modulation of leg-trajectory and to understand the control mechanism underlying quadruped locomotion. We focus primarily on the modulation of stiffness of the leg because the trajectory is a result of the interaction between the leg and the environment during locomotion. In this study, we present a “TEGOTAE”-based control scheme to modulate the leg stiffness. TEGOTAE is a Japanese concept describing the extent to which a perceived reaction matches the expected reaction. By using the presented scheme, foot-trajectories were modified and the locomotion speed increased correspondingly.