Volume 35, Issue 5 (September 2007)
Gearbox Fault Feature Extraction Using Hilbert Transform, S-Transform, and a Statistical Indicator
Vibration analysis has been widely used in machine fault feature extraction and diagnosis of rotating machinery. The effects of modulation and nonstationarity in vibration signals collected from a faulty gearbox present challenges for fault feature extraction. Hilbert transform and S-transform have the ability to address these issues through demodulation and time-frequency analysis, respectively. In this paper, we propose to use a feature indicator to represent the S-transform coefficients. The proposed method integrates the advantages of Hilbert transform, S-transform, and the proposed feature indicator (FI). The validity of the proposed method is verified with a simulated signal and real gearbox vibration signals. Comparison studies show that the proposed method is more effective and does not require the operators to have a lot of diagnostic experience.