Vibration-based damage detection in composite wingbox structures by HHT

A dynamic-based damage detection method for large structural systems using the Hilbert–Huang transform (HHT) has been proposed in this article. The proposed method has been verified numerically by implementing the scheme on a model of wingbox. In the implementation process, the following steps have been identified as being important: (1) axis-symmetry signal extension methods in order to solve the end effect problem of empirical mode decomposition (EMD), (2) finite element modelling for the purpose of establishing the base line, (3) a feature index vector for structural damage detection. The obtained results show that the damage feature index vector is more sensitive to small damage. Finally, the effect of noise is considered. Examination of the results confirms that the proposed damage detection method is very robust.