Wavelet Enveloped Power Spectrum and Optimal Filtering For Fault Diagnosis in Gear

The methodology of vibration based condition monitoring technology has been developing at a rapid stage in the recent years suiting to the maintenance of sophisticated and complicated machines. The ability of wavelet analysis to efficiently detect non-stationary, non-periodic, transient features of the vibration signal makes it a demanding tool for condition monitoring. In this paper, the vibration condition monitoring based on Laplace and Morlet wavelet enveloped power spectrum analysis to detect the faults in gears is presented. The experimental studies were conducted on the gear testing apparatus to obtain the vibration signal from a healthy gear and a faulty gear. The vibration signals obtained were filtered to enhance the signal components before the application of wavelet analysis. A study detailing features of fault characterization is also given in order to understand the effectiveness of signal processing methods. Keywords-Continuous wavelet transform, Envelope power spectrum, Wavelet, Filtering.