Robot Manipulators Tracking Using Hybrid Fuzzy Logic Controller

Abstract

This paper proposes a hybrid fuzzy controller \\vhich cOil1bines a conventional PD and a selftuning fuzzy logic controller (STFLC) for robot illanipulators trajectory tracking control. With the PD control as the preliminary component in maintaining the local stability of the entire system, the added STFLC provides fast responses to system variations and uncertainty in the robot dynamics. The STFLC considered ~elongs to a rule-based type, which uses linguistIC IF...THEN rules obtained by human expert and mean of maxima defuzzification method. The scaling factors of the input variables are self-tuned online to cover the entire universe of discourse of its membership functions based on some performance measurements. The proposed controller has been verified using simulation of a two-link robot arm to track sinusoidal reference input signals ~ith lo~d variation in the elbovv. I.