Robust H∞ output feedback control design for fuzzy dynamic systems with quadratic D stability constraints:: An LMI approach

This paper addresses the problem of designing a robust output feedback controller for a class of fuzzy uncertain dynamic systems that guarantees (i) the L-2-gain from an exogenous input to a regulated output is less or equal to a prescribed value and (ii) the closed-loop fuzzy system to be quadratically stable within a pre-specified LMI stability region. Based on an LMI approach, solutions to the problem are derived in terms of a family of linear matrix inequalities. In contrast to most existing results, the controller's premise variable is allowed to be different from the fuzzy model's premise variable. The chaotic Lorenz system is used to illustrate the effectiveness of the proposed design techniques. (C) 2005 Elsevier Inc. All rights reserved.