A dynamical variable structure control strategy in asymptotic output tracking problems

Using Fliess´ generalized observability canonical form, a dynamical discontinuous feedback strategy of the sliding-mode type is presented for asymptotic output tracking problems in nonlinear dynamical systems. A truly effective smoothing of the sliding-mode controlled responses is possible, while substantially reducing the chattering for the control input. The proposed approach represents a viable feedback alternative exhibiting attractive features such as robustness and, more importantly, a certain degree of input-output smoothness, dependent on the relative degree of the system. The author presents, along with computer simulations, an application example that illustrates the advantages of the proposed controller for a DC motor angular velocity tracking task