Gait-Free Planning for Hexapod Walking Robot

Abstract

This paper presents a gait-free motion planning approach for quasi-static walking of hexapod walking robots on terrains with limited available footholds. The proposed approach avoids using a prescribed gait pattern allowing an arbitrary sequence of leg swings. Furthermore, it is allowed that some legs do not need to be placed on the terrain for an extended duration. The proposed method is based on a decomposition of the motion planning into: (i) finding a candidate sequence of stances and intermediate configurations representing plausible steps using a graph-search; and (ii) connecting the intermediate configurations by feasible paths satisfying the motion constraints of the walking robot. The individual one-step paths are determined using a Bézier curve-based parametrization that seems to be sufficient for the relatively simple paths of a single step, and the low-capacity parametrization yields natural-looking motion.