Strain Rate Self-Sensing of a Piezoelectric Material with the Phase Delay Compensation.

Abstract

This paper deals with the analytical modeling, and the experimental verification of the strain rate self-sensing mechanism for a cantilevered piezoelectric beam. The piezoelectric beam consists of two laminated lead zirconium titanates (PZT) on a metal shim. A mathematical model of this beam dynamics is derived by the Hamilton's principle. It turns out that a method using an adaptive filter for the strain rate estimation of a piezoelectric beam works not properly due to the phase delay effect in a piezoelectric material and the structural shortcomings of an adaptive filter. In order to reduce the phase delay effect of the piezoelectric material on the performance of a strain rate self-sensing mechanism, a circuit for the phase delay compensation is devised. A systematic mechanism for the better strain rate estimation of a cantilevered piezoelectric beam compared to that using an adaptive filtering is proposed. The efficacy of this method is investigated through the comparison of experimental results with those from the analytical method.