Use of the Vibroacoustic Signal in Diagnostics of Early Stage Failure

In recent years, there has been an increasing interest in applying higher order spectral analysis and time-frequency representation of vibroacoustic signals to the early stage failure diagnostics of rotating machinery. Vibrations of such machinery are produced as a combination of periodic and random processes due to rotation of a machine cycles and the effect of the surrounding. In this paper, the main tools for the analysis of higher order spectra and time-frequency representation are presented. A comparison of simulated data subjected to the signal amplitude-phase modulation phenomena due to failure development and test bed investigations of fatigue-related breaking of a tooth is made.