Force control for hexapod walking robot with torque observer

This paper describes a new force control method for a hexapod walking robot developed for the purpose of transportation in rough terrain. In unstructured terrain such as soil and gravel, walking robots require the force control to keep its stability. Normally, soft surfaces such as soil has hysteresis characteristics. Thus, general force control, which sometimes shows overshoots is not desired. On this point of view, our new force control uses torque observer and avoids overshoot by a simple strategy. And, we also employed a notion of autonomous distributed control. The distributed controllers placed on each leg decide their own manner with referring information from central controller. We also confirmed the validity of our method by several kinds of numerical simulation