In this paper results of damage assessment of composite panels using guided wave propagation phenomenon are presented. Elastic waves excitation is based on an air-coupled transducer (ACT) while the waves sensing is based on scanning laser Doppler vibrometry. It thus forms the full non-contact diagnostic approach. Thin panels made of fibre-reinforced polymer are investigated. The problem of optimal slope angle of ACT and the possibility of symmetric and antisymmetric elastic wave modes excitation is investigated. Research is related to the detection and localisation of artificial damage (additional mass, Teflon inserts). Moreover, the influence of single and multiple acoustic wave sources on artificial damage localization results and the problem of panel coverage area by elastic waves with large amplitudes to improve damage sensitivity are investigated. Different locations of ACTs and their influence on damage detection results are investigated. Two damage imaging algorithms based on elastic waves have been proposed, namely root mean square (RMS) energy maps and wavefield irregularity mapping (WIM). Moreover, results of simulations of elastic wave generation using ACT in CFRP plate based on a combination of FEM method and spectral element method (SEM) are presented. For this purpose COMSOL software and in-house MATLAB code are utilized, respectively
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