The interpretation of the bispectra of vibration signals— II. Experimental results and applications

Third-Order Spectral Techniques for the Diagnosis of Motor Bearing Condition Using Artificial Neural Networks

“…The most significant frequency in the power spectrum appears around 125 Hz and is due to a combination of the fundamental (25 Hz) and third harmonic (100 Hz) of the rotation frequency. There are also peaks around the bifrequencies (25, 100) and (100, 25) Hz indicating that the bispectrum measures the amount of coupling between the three spectral components 25, 100 and 125 Hz according to equation (5), the sum of the two frequencies 25 and 100 Hz resulting in the 125 Hz component.…”

“…Frackrell et al [25] has shown that the application of bicoherence features to condition monitoring is useful since they are independent of the measurement position. It is for these reasons that bicoherence spectra, calculated using equation (14), have also been used in this study.…”

Analysis of the Frequency Response Function for Linear and Quadratic Non-Linear Systems Using Vector Notation

“…Kim and Park [10] proposed a frequency domain identification method for non-linear joint force dynamic models. Fackrell et al [11,12] investigated non-linear interaction phenomena by bispectra analysis and performed experimental analysis, such as on simple loose beam vibration and vacuum cleaner noise.…”

Global crack detection using bispectral analysis

“…Attempts to use these effects to detect cracks have typically concentrated on using the power spectrum to quantify the signals produced by the nonlinear behaviour, although the advantages of the bispectrum in detecting quadratically-phase-coupled signals [5][6][7][8][9] has lead to some interest in using the bispectrum in crack detection [10][11][12][13][14]. As the increase in crack length results in an increase in the bispectrum value corresponding to the mixing frequency [1] that bispectrum value is useful as a measure of the damage.…”