Dynamic wavelet-based tool for gearbox diagnosis

This paper proposes a novel wavelet-based technique for detecting and localizing gear tooth defects in a noisy environment. The proposed technique utilizes a dynamic windowing process while analyzing gearbox vibration signals in the wavelet domain. The gear vibration signal is processed through a dynamic Kaiser's window of varying parameters. The window size, shape, and sliding rate are modified towards increasing the similarity between the non-stationary vibration signal and the selected mother wavelet. The window parameters are continuously modified until they provide maximum wavelet coefficients localized at the defected tooth. The technique is applied on laboratory data corrupted with high noise level. The technique has shown accurate results in detecting and localizing gear tooth fracture with different damage severity.

► Wavelet multi-resolution analysis (WMRA) technique for gear damage monitoring.
► Maximum resolution coefficients of WMRA localize cracks in gear teeth.
► WMRA technique detects very small cracks from signals with low SNR of −15 db.