A bio-inspired damage detection approach based on multi-scale wavelet finite element

The human retina consists of two regions, namely, low-acuity peripheral vision and high-acuity central foveal vision, thereby guaranteeing an efficient tradeoff between a wide field of view and important image details. Detection of structural damage is, to a great extent, analogous to the acquisition, tracking, and recognition of targets in vision systems. Therefore, the superior retinal structure provides ingenious insight into an ideal damage detection strategy in which structural modeling scales are not only spatially variable but also dynamically changed according to actual needs. This study employs a novel beam-type wavelet finite element model (WFEM) based on the second-generation cubic Hermite multiwavelets to fulfill a bio-inspired multi-scale damage detection strategy. Dynamical equations of beam structures are derived in the context of the WFEM. Through a multi-stage updating of the WFEM, damage in beam structures can be detected in a progressive manner: the suspected region is first identified using a low-scale structural model, and the more accurate location, extent, and severity of the damage can be identified using a multi-scale model with local refinement. The multi-scale WFEM can considerably facilitate the adaptive change of modeling scales. The numerical examples clearly demonstrate that the proposed approach can efficiently locate and quantify damage with minimal computation effort and a limited number of updating parameters.