Geometric Design of a Walking Machine for Optimal Mobility

The design of the geometry of a walking machine depends to a considerable extent on the applications for which the machine is intended. Nevertheless, there are some very general principles and approaches which may be applied. This paper deals with the geometric design of a hexapodal walking machine which is to possess optimum mobility on varied terrain. This problem both illustrates, and serves as a vehicle for, the development of these general principles. Since one of the most important features of legged locomotion is the gait, the fundamental gaits of a 2N -legged (N ≥2) walking machine on both flat and irregular terrain are introduced first. The motion of the machine is assumed to be quasi-static. The mobility of a walking machine using these gaits, mainly centered on the hexapodal case, is then discussed. The principles obtained in gait and mobility studies are then applied to the design of the geometry of a hexapod, which includes both body-leg layout and leg walking volumes (working spaces), so that the hexapod may possess the optimum mobility.