A Parametric Study on Admittance Signatures of a PZT Transducer Under Free Vibration
Piezoelectric material is proven to be a versatile collocated sensor and actuator. Its specific application includes electromechanical impedance (EMI)-based structural health monitoring (SHM). To date, several EMI models are available in the literature but parametric studies are scarcely available. This study aims at providing a parametric study on selected models, considering a freely vibrating piezoelectric transducer. The effect of varying mechanical and electrical parameters of the transducer on the admittance signatures was investigated. The theoretical results were compared against the experiments. Accuracy of the model was successfully refined upon model updating.
Abstract The problem of diagnosing a fault or a perturbation in a dynamical system (be it industrial or natural) can be restated as the characterization of the transfer function of a filter that acts on a “sane” or “unperturbed” system to transform it into a “faulted” or “perturbed” one. This filter would then be approximated as time-invariant (and linear) only for short time windows, while the time evolution of such transfer function on longer time scales leads to a simple but powerful general framework that allows to diagnose the onset and/or the time evolution of a fault or perturbation of the system.