A Signal Processing Approach for Elastic Wave-Based Structural Health Monitoring Using Active Piezoelectrics
A series of digital frequency filters (DFFs) were designed to screen diverse noises and the spectrographic analysis was conducted to isolate complex boundary reflection, which obscures the damage-induced signals. The scale-averaged wavelet power (SAP) technique was applied to enhance the measurement accuracy of Time of Flight (TOF). As an example, the propagation characteristics of elastic wave in a structural beam of square cross-section were analyzed using such an approach and verified experimentally and numerically, with the consideration of the complicated wave scatter caused by the non-ignorable section dimensions.
J.K. Kim, D.Z. Wo, L.M. Zhou, H.T. Huang, K.T. Lau and M. Wang
C. H. Yang et al., "A Signal Processing Approach for Elastic Wave-Based Structural Health Monitoring Using Active Piezoelectrics", Key Engineering Materials, Vols. 334-335, pp. 1141-1144, 2007