Robust sliding mode control of robotic manipulators with model uncertainty and external environmental disturbances

Abstract

A new control scheme is presented in this work for robotic manipulators with model inaccuracies and external disturbances. The strategy is designed in two stages. First, a nonlinear controller is designed on the basis of the nominal system model to satisfy prescribed trajectory-tracking constraints. This controller is constructed by combining analytical dynamics with the governing equations of constrained motion. Second, a robust control algorithm is presented to minimize the adverse effects of model uncertainties and environmental perturbations in manipulator operation. Built on a generalized sliding mode control framework, the robust controller provides continuous control action and eliminates chattering. Results from simulations verify the practicability of this method, which achieves precise trajectory tracking amid parameter uncertainties, external disturbances and initial tracking deviations.