Fuzzy-logic control of dynamic systems:: from modeling to design

A systematic methodology for the synthesis and analysis of fuzzy-logic controllers for multi-input multi-output nonlinear dynamic systems is proposed in this paper. A robust model-based control structure is suggested that includes the fuzzy-logic dynamics model of the system and several robust fuzzy control rules. The fuzzy-logic model is systematically constructed from the input-output data, and the robust control rules are designed using the sliding-mode control theory. The stability and completeness of the control structure is guaranteed, based on a generalized formulation of the sliding-mode control developed in this paper. The proposed fuzzy-logic control scheme has been applied to trajectory control of a four-degree-of-freedom robot manipulator, and was compared with high-gain PID controllers. Superior tracking performance was achieved. (C) 2000 Elsevier Science Ltd. All rights reserved.