電気・油圧サーボ系の自己調整ファジィ制御

抄録

Recently, the fuzzy control algorithm is frequently applied to various kinds of systems due to its simple algorithm, good adaptability to complex and nonlinear systems, etc. One of the problems when applying the fuzzy control algorithm is the tuning method of fuzzy control parameters for obtaining the optimum conditions. This study deals with a self-tuning fuzzy controller (STFC) applied to an electro-hydraulic servo system. The STFC has a hierarchical structure consisting of an algorithm being identical to a fuzzy controller at the lower loop and a tuning algorithm assisting the performance evaluation and parameter modification function at the upper loop. As for the algorithm for tuning at the upper loop, another fuzzy logic was adopted for constructing a fuzzy self-tuner. The whole procedure of STFC was repeatedly performed until an acceptable control level was achieved. The STFC must be able to assess its performance in order to improve its control strategy. The basic functions of STFC can be summarized as follows : (a) to provide appropriate control action while evaluating the performance, (b) to modify the control action based on this evaluation.
It could be verified by experiment and digital simulation that the STFC developed in this study was useful and effective for the control of the electro-hydraulic servo system.