Theoretical and Experimental Investigation of Spur Gearbox with Cracked Pinion Tooth Using Dynamic Model for Condition Monitoring

Abstract

Gearbox dynamic modeling is used to understand the effect of presence of gear tooth fault and the role of change in mesh stiffness on vibration response using computer simulation of a geared system. In the present study, a ten degree of freedom dynamic model is formulated to demonstrate the effect of tooth fault and mesh stiffness variation on the dynamic of geared system. Further, for experimental study the crack path is generated using finite element analysis based on fracture mechanics in pinion tooth profile. Experiments have been performed on a drivetrain diagnostic simulator using single-stage spur gear box and the vibration signals have been recorded for healthy and cracked pinion tooth. The wavelet de-noising technique is adopted to remove the unwanted noise from the vibration signals. A modulation sideband approach in conjunction with conventional frequency spectrum visualization has been introduced. A comparison of analytical and experimental results using classical sideband analysis have been outlined, and it is concluded that the proposed methodology helps in fault detection with increased deterioration level.