SELF-ORGANIZING FUZZY-LOGIC CONTROLLER-DESIGN

The fuzzy logic controller based on the fuzzy set theory provides a useful tool for converting the linguistic control strategy from the expert knowledge into automatic control rules. However, proper control rules cannot always be obtained easily for a complex plant. The self-organizing fuzzy logic controller is a heuristic controller where control rules are generated and improved automatically. Its basic functions are: (1) to generate appropriate control action according to the evaluation of the system's behaviour; and (2) to modify the control action based on system performance evaluation. In this paper, the behaviour of the system with respect to the performance index is investigated. A systematic method to modify the performance index table such that the required system time response is achieved is proposed. A ball and beam apparatus has been used to illustrate the effectiveness of the proposed control structure.