Optimal leg design in a hexapod walker

Leg performance during walking was examined with a computer model of a planar leg built of three segments. The service zone, where the leg tip may reach, is non-homogenous with respect to leg performance efficiency. The subzones in the anteromedial, posteromedial and mediolateral parts of the service zone provide approximately straight leg tracks and minimal rocking under the simplest control (i.e. there is proportional change of all the joint angles from their start values to their finish values). Legs of real insects are arranged in these three subzones, or at least in two of them. In the central subzone, the rocking can be large and the particular control system which controls the straight leg tracks may be necessary. The control system must activate some muscles twice for each stepping cycle. The skew alignment of the proximal leg articulation is necessary for the adjustment of various stance widths on the plane and on the narrow ground.