Detection of localised defects in rolling element bearings via composite hypothesis test

✍ Scribed by Jun Ma; James C. Li

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 582 KB
• Volume: 9
• Category: Article
• ISSN: 0888-3270
• DOI: 10.1006/mssp.1995.0005

✦ Synopsis

A new scheme for detection and diagnosis of localised defects in rolling element bearings, using hypothesis test theory is described. It is observed that the vibration of damaged bearings consists of two alternating zero-mean Gaussian components, with different variances, representing background noise and defect signature respectively. Theoretically, the switching between these two distributions will occur at the rate that rolling elements pass over a defect. To classify the bearing vibration at a given instant as one of the two distributions, a uniformly most powerful hypothesis test, in the sense of Neyman-Pearson criterion, is designed. By using this hypothesis test and then checking the switching frequency, a localised defect can be detected. The effectiveness of the scheme is confirmed by experiments on bearings with a single defect at different locations and under different loads.