Full Leg Control of a Quadruped Robot Using Linear Visual Servoing with a Stereo Omnidirectional Camera

The authors have previously proposed foot tip control for quadruped robots using linear visual servoing (LVS) with a normal stereo camera. However, a normal stereo camera has a narrow field of view and is incapable of seeing all four legs simultaneously. Consequently, it has been a problem that the control of all the legs have required that the rotatation of the camera be controlled. This article proposes a method by which a stereo omnidirectional camera is provided at a position low on the body to control all four legs through LVS. In this article, we at first present a transformation equation from an omnidirectional image to a binocular visual space, and we develop a servo equation of LVS in which an omnidirectional image is used. Then, through simulation, we confirm trajectories with the LVS applied to foot tip control. We also conduct an experiment using TITAN- VIII to demonstrate the efficacy of the proposed method.