Design and implementation of PI and fuzzy PID supervisory controllers for a flexible link robot

Abstract

In this paper, PID controllers are designed to enhance the trajectory tracking performance of a flexible link robot. Firstly, a PI controller is used where conventional Ziegler-Nichols method adjusts the controller parameters. In addition, Fuzzy PID controller is designed in which fuzzy rules are utilized on-line to tune the PID controller parameters based on the current value of error and its first time-derivative. Also, effects of several defuzzification methods on the closed-loop system are investigated in this paper. A flexible link robot is implemented and controllers are applied. Experimental results confirm the performance of the fuzzy PID controller.