Variable Universe Fuzzy Adaptive PID Control in the Digital Servo System

To solve the non-linear problem in our laboratory's digital servo system, a variable universe fuzzy adaptive PID control method is introduced in this paper. With the variable universe theory, a flex-factor controller based on fuzzy rules is designed to adjust the quantization factor and scale factor dynamically. PID control and variable universe fuzzy adaptive PID control are analyzed and compared by using MATLAB RTW/RTWT toolbox in our laboratory's digital servo system. The results show that the variable universe fuzzy adaptive PID control method has better dynamic response performance and adaptive ability with less overshoot, shorter adjusting time and higher tracking accuracy.