Elastic Properties Inversion of an Isotropic Plate by Hybrid Particle Swarm-Based-Simulated Annealing Optimization Technique from Leaky Lamb Wave Measurements Using Acoustic Microscopy

Towards real-time assessment of anisotropic plate properties using elastic guided waves

“…39 Alternatively, few authors proposed to directly use the dispersion equation as objective function F D ðhÞ. 16,19 The idea is to evaluate Eq. (1) on the experimental data (k n , f n ), with…”

“…Broadband signals can be acquired with a diversity of techniques, like a piezoceramic transducer for emitting and a laser scanning Doppler vibrometer for sensing, 13 laser-ultrasound, 14,15 or line-focus acoustic microscopy. 16 Spatio-temporal broadband signals recorded at equally spaced points are twodimensionally (2-D) Fourier transformed to obtain the frequency spectrum of the different propagating modes in the frequency-wave number plane. 17 Then, for comparison with theoretical results, this information is generally processed to extract the ridges of the measured dispersion curves in terms of frequency-wave number data pairs.…”

“…Although scarcely discussed in the literature, their automatic detection can be problematic due to mode superposition and limited spatial resolution. 18 To carefully extract the dispersion curves, a) Electronic mail: claire.prada-julia@espci.fr visual operator selection, 19 peak-finding algorithms and interpolation, 13 image tracing algorithm, 16 matrix pencil method, 20 and more advanced data processing algorithms, as reviewed in Refs. 21 and 22, have been developed, often at the cost of time-consuming procedures.…”

“…5,23 However, it should be noted that a clear identification of the modes in experimental data is uncertain, especially for higher-order modes. 16,19 In this way, Karim et al 6 presented a numerical procedure for the inversion of LLW data to determine certain material properties of a composite laminate using a modified version of the simplex algorithm. For this approach to be effective, four broadband transducers were used to record the phase velocities over a wide frequency range and three measurements in different propagation directions were needed to recover the full set of independent elastic coefficients.…”

“…For this approach to be effective, four broadband transducers were used to record the phase velocities over a wide frequency range and three measurements in different propagation directions were needed to recover the full set of independent elastic coefficients. In another related study, Yan et al 16 described a method for the inversion of the elastic properties of plates by line-focus acoustic microscopy using a hybrid particle swarm-based-simulated annealing optimization. However, this approach required tedious data processing for converting time-domain waveforms into dispersion curves and was solely applied to a thin isotropic plate.…”