Robust Nonlinear Control Of Robotic Manipulators by the Method of Computed Torque

The method of computed torque or inverse dynamics has gained some success as an approach for nonlinear control of robotic systems. Exact knowledge of the system parameters is required, however. This paper addresses the problem of nonlinear control when the robotic system exhibits parameter variation. The approach is based upon decoupled model following using a trajectory sensitivity function. Control of a three degree of freedom manipulator arm under mass variation is discussed, as an example.