Early damage detection in composite wingbox structures using Hilbert-Huang transform and genetic algorithm

A vibration-based approach to detect crack damage for large structural systems by using the Hilbert-Huang transform (HHT) has been proposed. The proposed method has been numerically implemented on a composite wingbox. In the implementation process, the following steps have been identified as being important: (a) An optimization procedure is developed by genetic algorithm (GA) in order to determine the location of piezoelectric sensor for damage detection in a composite wingbox; (b) To solve the end effect problem of empirical mode decomposition (EMD), axis-symmetry signal extension method is introduced; (c) Finally, a damage detection method by using HHT is developed. Furthermore, the effect of noise is considered. Examination of the results confirms that the identification method is very robust.