Adaptive Fuzzy Logic Control of a Flexible Four-Bar Mechanism With a Smart Coupler Link

Abstract

This paper presents the results of an investigation in which a PD-like and adaptive Fuzzy Logic Controllers (FLC) are designed to reduce the effects of the most dominant vibration mode on the elastodynamic response of a flexible mechanism system. The FLC schemes are implemented on a flexible four-bar mechanism whose coupler link is retrofitted with a pair of thin plate-type piezoceramic actuator and sensor bonded to the coupler link surface at the high strain location corresponding to the dominant vibration mode. Simulation results indicated that active damping with FLC is a viable strategy in reducing the amplitudes of vibrations. Moreover adaptive FLC with fixed, optimally obtained adaptation rates provides higher attenuation rate than with fuzzy adaptation mechanism. However, a simple robustness test indicated that fuzzy adaptation is more robust tan fixed adaptation.