State feedback effects in fuzzy logic control: a fuzzy modeling approach

Fuzzy set theory and the fuzzy logic controller are reviewed. A fuzzy modeling algorithm that can construct a set of fuzzy linguistic rules to imitate the behavior of a state feedback and/or PID controller is presented. The outputs of both the fuzzy and the state feedback schemes are displayed as 3-D diagrams and the mean square error is minimized over the parameter β. Three properties of the proposed algorithm and its extensions to the n-variable case and to the PID controller are presented. An inverted pendulum system is used to compare the performance of the two control schemes. It is concluded that a fuzzy controller should be able to achieve a performance at least as good as that of a state feedback controller, if property designed