Robust adaptive sliding mode control for uncertain nonlinear MIMO system with guaranteed steady state tracking error bounds

In this paper, a robust adaptive sliding mode controller is proposed for a class of uncertain nonlinear multi-input multi-output (MIMO) systems. The upper bounds of the uncertainties are not needed in the procedure of the controller design, and the controller is continuous, which guarantees that the tracking error can converge to a small residual set. Furthermore, explicit formulas are given that allow for calculating the size of the residual set, and the bounds of the tracking errors at steady state can be specified a priori and guaranteed by choosing certain design parameters. Finally, a simulation study based on a two-link rigid robotic manipulator model is used to illustrate the effectiveness of the proposed controller.