Strain self-sensing of a piezoelectric material using phase delay compensation

This paper deals with analytical modeling and experimental verification of strain self-sensing. Three strain self-sensing methods are investigated, including a conventional method with a capacitance bridge, an adaptive filter, and phase delay compensation to minimize the effect of the phase delay from a piezoelectric material. The piezoelectric beam consists of two laminated lead zirconium titanates (PZT) on a metal shim and generates bi-directional movement. A mathematical model of the beam dynamics is derived by Hamilton's principle, and the accuracy of the modeling is verified by comparison with experimental results. The efficacy of these methods is investigated by comparison of the experimental results with a prediction from the derived analytical model. It turns out that the method using the newly proposed phase delay compensation gives more accurate results for strain self-sensing performance than each of the other two methods.