Fusion method for processing non-contact multi-sensor acoustic signals in rolling bearing fault diagnosis

Aiming at the problem that there are overlaps in the signals collected by multi-sensor from a fault source and the fault information of these signals are incomplete when mobile rolling bearing is tested with non-contact acoustic emission, a non-contact multi-sensor acoustic signals fusion method for rolling bearing fault was presented based on the theory of acoustic wave propagation. The time difference relationship between multi-sensor acoustic signals and the impact frequency of the typical faults for rolling bearing were comprehensively considered. A test bed for acoustic emission testing regarding rolling bearing fault was established to collect the acoustic signals of rolling element, outer ring and inner ring faults of mobile rolling bearings. The signals emitted from the same sound source were processed with the fusion method. The fused signals were proved to be more tightly correlated with the fault source than the individual signal of each sensor. By means of the fusion processing, the acoustic signals of different rolling bearing faults were analyzed with the acoustic emission cumulative impact counting method. The results show that with the fusion method, the signals emitted from the same sound source received by multi-sensor can be processed effectively, and the faults can be diagnosed accurately using the signals after fusion.