A HIERARCHICAL STRATEGY FOR PLANNING CRAB GAITS OF A QUADRUPED WALKING ROBOT

A method of planning crab gaits for a quadruped walking robot is propo sed. In the conventional gait study, one of the major concerns has bee n the foothold selection based on a prescribed body motion, but, in th e paper, we consider the body motion planning problem under the assump tion that a set of irregular footholds is given, and propose a hierarc hical strategy. The strategy can be divided into three stages: first, a feasible range of the body movement is sought under the kinematic li mit and the stability constraint. Next, a swing-leg sequence is select ed with the aid of a proposed measure of traversability. Finally, an o ptimal sequence of the body motion is planned by the proposed procedur e of otpimizing the gait stability margin. To verify the efficiency of the proposed method, simulation results are presented.