SLIDING MODE CONTROL WITH FIXED AND FUZZY SLIDING SURFACES

Abstract

Reaching time plays an important role for the multi-coupled system like robot manipulator to achieved the minimum reaching time various method has been suggested. Variable structure system with sliding mode is one of the technique. Fuzzy controlled switching surface minimizes the reaching time up to distinct level. Instead of using conventional sliding mode controller having linear time varying switching surface, if fuzzy logic is used to regulate the. switching surface, the reaching .time of the system trajectory is shorter than in the fixed method and having better performance than the conventional method in reaching time. In this dissertation the fuzzy controller is used to regulate the switching surface and its performance is compared with fixed switching surface. The proposed PLC is designed using a very simple control rule base and most natural and unbiased membership function (symmetrical triangles with equal bases and 50%, overlap with neighboring MFS)