Rolling bearing performance degradation assessment based on the synchroextracting transform and complex wavelet structural similarity index

In order to detect rolling bearing abnormities earlier and quantify the degree of performance degradation, a new evaluating method was proposed based on the synchroextracting transform and complex wavelet similarity (SET-CWSS) index. The time-frequency analysis of a vibration signal at current moment was performed by the synchroextracting transform (SET) to get a more concentrated time-frequency graph. The time-frequency graph obtained after SET and the SET time-frequency graph of the fault-free vibration signal when the bearing was just put into operation were compared on the basis of complex wavelet structural similarity (CWSS). And then, the SET-CWSS index for the assessment of rolling bearing performance degradation at current moment was achieved. Through the fatigue test verification and comparisons with other performance degradation assessment methods, the results show that the SET-CWSS index can effectively describe the performance degradation process of rolling bearings, quantify the degree of performance degradation and is more sensitive to the early abnormities of rolling bearings. © 2020, Editorial Office of Journal of Vibration and Shock. All right reserved.