Design of a fuzzy logical controller by immune algorithm with application to an inverted pendulum system

Fuzzy logical controller is one of the most important applications of fuzzy-rule-based system that models the human decision processing with a collection of fuzzy rules. Choosing appropriate fuzzy rules and sets is essential for a fuzzy logic controller to perform at the desired level. In this paper, an immune evolutionary algorithm is proposed based on the evolutionary principle in the immune system. The algorithm is used to design a fuzzy logic controller automatically for real-time control of an inverted pendulum. In order to avoid the combinatorial explosion of fuzzy rules due to multivariable inputs, state variable synthesis scheme is employed to reduce the number of fuzzy rules greatly. Experimental results show that the designed controller can control actual inverted pendulum successfully.