Evolutionary Algorithms for Fuzzy Control System Design

This paper provides an overview on evolutionary learning methods for the automated design and optimization of fuzzy logic controllers. In a genetic tuning process, an evolutionary algorithm adjusts the membership functions or scaling factors of a predefined fuzzy controller based on a performance index that specifies the desired control behavior. Genetic learning processes are concerned with the automated design of the fuzzy rule base. Their objective is to generate a set of fuzzy if-then rules that establishes the appro-priate mapping from input states to control actions. We describe two applications of genetic-fuzzy systems in detail: an evolution strategy that tunes the scaling and membership functions of a fuzzy cart-pole balancing controller, and a genetic algorithm that learns the fuzzy control rules for an obstacle-avoidance behavior of a mobile robot. Keywords—Evolutionary algorithm, fuzzy control, genetic fuzzy system, mobile robot. I