Robust motion control for robots with flexible elements

A new method for controlling the compliant motions of robots is described. This method intends to use such control laws that generate potential or quasi-potential control forces acting on the control object-a manipulator mechanical system of a robot. This provides very simple and natural stability conditions for the closed loop of the system for controlling the compliant motions of a robot since, in this case, the manipulator is a mechanical system, on which only potential and quasi-potential forces act, as well as dissipative forces induced by friction. Moreover, in this case, the dynamical properties of the system are barely affected by the variation of its parameters, i.e., the control is robust. The proposed new control laws have a very simple structure and involve feedback signals that are easy to measure, which is important in their practical implementation. The proposed approach is applicable to any real manipulator robots, which always have elastic compliance in the joints and wrist. It can be also applied to manipulators with flexible links.