Detecting Low-Velocity Impact Damage in Composite Plates via a Minimization of Measured and Simulated Origin Approach

In this paper, a new method for identifying impact locations applying a comparative simulated approach of minimization of measurement error against simulated data in a composite carbon plate-like structure using acoustic Lamb wave is proposed and reviewed. The purposed model detects impact locations by using an error minimizing algorithm based on the measured Lamb waves from an actual real impact and demonstrates a high-level of flexibility. Furthermore, the proposed model can be straightforwardly calibrated for different velocities and other parameters inherent in carbon-based structures, reducing the effects of the structure's anisotropic properties. In particular, the time of arrival of an impact signal is calculated by applying wavelet transform and threshold crossing methods. Experiment results illustrate the effectiveness of the proposed method by presenting a very accurate detection rate of real low-velocity impacts on a carbon-based plate-like structure. This promising technique enables inspection and on-line monitoring of impacts on composite structures. Further developments of the suggested model are discussed, and are mainly focused on producing a velocity independent extension mode.