Fig. 1. Schematic diagram of 3D-DIC

Fig. 2. Schematic diagram of DIC noise frequency domain decoupling

Fig. 3. Schematic diagrams of damage detection experimental setup and stroboscopic down-sampling strategy. (a) Schematic diagram of experimental setup; (b) schematic diagram of stroboscopic down-sampling

Fig. 4. Schematic diagrams of cantilever plates. (a) Cantilever plate Ⅰ; (b) cantilever plate Ⅱ

Fig. 5. Fourier spectra of vibration response. (a) Fourier spectrum of sample I; (b) Fourier spectrum of sample II

Fig. 6. Flow chart of structural damage detection method

Fig. 7. Modal shape of cantilever plate I. (a) DIC measurement results; (b) bandpass filtering for noise reduction of DIC measurement results; (c) Ansys simulation results

Fig. 8. Modal assurance criterion. (a) 2D plot of modal assurance criterion; (b) 3D plot of modal assurance criterion

Fig. 9. Damage detection of cantilever plate I. (a) DIC measured modal shape and Chebyshev polynomials fitting results; (b) damage detection results of DIC measurement data; (c) DIC measured modal shape after noise decoupling and Chebyshev polynomials fitting results; (d) damage detection results of DIC measurement data after noise decoupling

Fig. 10. Damage detection of cantilever plate I. (a) Modal shapes of DIC data; (b) residuals based damage detection results with DIC data; (c) modal shapes of filtered DIC data; (d) residuals based damage detection results of filtered DIC data

Fig. 11. Damage detection of cantilever plate II. (a) Modal shapes of DIC data; (b) residuals based damage detection results with DIC data; (c) modal shapes of filtered DIC data; (d) residuals based damage detection results with filtered DIC data