A cross-coupled bistage fuzzy controller for biaxis servomechanism control

This paper presents a methodology to design a cross-coupled bistage fuzzy controller for cross-coupled servomechanisms. In the bistage fuzzy inference, the consequence in the first stage is passed to the second stage as fact and the consequence of the second stage is used as the control input. The proposed approach is used to reduce the complexity of the fuzzy system. A more systematic method which is based on a performance index of the fuzzy control system is developed to generate bistage fuzzy rule sets. To show the effectiveness, the proposed approach is applied to control a cross-coupled biaxial servomechanism system which is difficult to obtain by an accurate nonlinear mathematical model in the case of a circular trajectory. Simulation results have shown that the desired contouring the accuracy can be achieved, and the proposed approach outperforms the uncoupled approaches. (C) 1998 Elsevier Science B.V. All rights reserved.