Squeeze damping of giant electrorheological fluid tuned by pulse width modulation

Abstract

Smart rheological materials represented by giant electrorheological fluid (GERF) have attracted considerable attention in vibration isolation, microfluidics, and robotics. The traditional control method is primarily to adjust the amplitude of the constant voltage. This paper introduces a GERF damper that works in squeeze mode and uses varying pulse width modulation (PWM) voltage for damping adjustment. The influence of PWM voltage parameters on the damping characteristics of the damper is analyzed through experiments. The similarities and differences between the constant voltage and PWM voltage are discussed. PWM voltage can obtain larger equivalent damping with small duty cycles. A parametric model is established based on the squeeze flow principle to describe the damping characteristics of the damper. The root mean square error between the experimental and model results is less than 0.015, which verifies the accuracy of the model. The results of the vibration platform test show that the PWM voltage control can adjust the transmissibility of the damper in the frequency domain. The amplitude of the vibration is reduced by 56% in the time domain. This study provides a new damping adjustment method for GERF dampers.