Robust dynamic integral sliding mode for MIMO nonlinear systems operating under matched and unmatched uncertainties

In this research, a class of output feedback linearizable MIMO nonlinear systems isconsidered to be affected by both matched and unmatched uncertainties. The design of outputfeedback control law relies on an integral manifold, which permits subdivision of the controldesign architecture into two steps. In the first step, pole placement based continuous controlcomponent is designed, which regulates the system output when sliding mode is established. Inthe next step, a discontinuous control component is designed to cope with the uncertainties. Inthe proposed approach, the control input is applied to the actual system after passing through achain of integrators. Consequently, the well-known chattering phenomenon, being caused by highfrequency oscillations against the sliding manifold, is reduced and thus a continuous control inputis fed into the system. This is a clear benefit in many applications, such as those of mechanicalnature where a discontinuous control action could be inappropriate. The proposed control lawis theoretically analysed and its performance in term of output regulation to zero is witnessedby the simulation results of two illustrative example.