Discrete Variable Structure Control for Linear Multivariable Systems

Abstract

This paper presents a state feedback discrete variable structure controller for robust tracking of linear multivariable systems with unmatched, additive uncertainties. Extension of the controller to output feedback using a prediction observer with bias estimation is also given. It is shown that the state feedback controller guarantees attractiveness and invariance of a boundary layer, while the output feedback controller does so after a transient. Unlike existing schemes, the controllers utilize a single sliding hyperplane regardless of the number of inputs. This attribute enables the development of a procedure that admits, under minor restrictions, direct application of well-established linear control strategies in the design of tracking error dynamics. A numerical example is used to illustrate the proposed controllers. [S0022-0434(00)01904-3]