A full order sliding mode tracking controller for direct drive robot manipulators

This paper presents the development of a full order sliding mode controller for tracking problem of direct drive robot manipulators. By treating the arm as an uncertain system represented by its nominal and bounded parametric uncertainties, a new robust full order sliding mode tracking controller is derived such that the actual trajectory tracks the desired trajectory as closely as possible despite the nonlinearities and input couplings present in the system. A proportional-integral sliding surface is chosen to ensure the stability of overall dynamics during the entire period i.e. the reaching phase and the sliding phase. Application to a three DOF direct drive robot manipulator is considered.