| Popis: |
Nonlinear wave modulation (NWM) is a nonlinear health monitoring technique that allows for the early detection of minor faults and damages. The purpose of this study is to develop a novel, low-cost and portable device to improve the damage index (DI) in the NWM. 2D spectral finite element method is used to model the electromechanical coupling between piezoelectric patches, an inductor and a structure in a feasibility study. In the simulation, an inductor is attached to each actuator to compare the results with those without an inductor. A specific inductance value is selected for the piezoelectric transducer to achieve resonance, which results in an increased voltage amplitude. A circuit that is inexpensive and portable has been designed and implemented. The results of two experimental setups, an aluminum beam with boundary loosening and a sandwich panel with bolt loosening as damage, are compared with those of the NWM without an inductor. The average of sidebands as a DI is then compared for various frequency combinations using the two NWM techniques i.e. with and without an inductor. |
