Advanced Higher Order Spectra for Classification of Damage in Transient Conditions

A generalization of the higher order spectra is proposed for damage classification for transient signals with any nonlinear time variation of the instantaneous frequency. The generalized transform is applied for the exponential variation of the instantaneous frequency and compared with partially adapted and non-adapted generalized transforms and the classical higher order spectra. It is shown that in transient conditions the fully adapted generalized transform is more effective for damage classification than the classical higher order spectra, partially adapted and non-adapted generalized transforms.