Non-Contact Full-Field Bearing Condition Monitoring and Fault Diagnosis Using Millimeter-Wave Radar

As one of the most critical components of rotating machinery, the bearings are prone to failure and directly affect the stable operation of mechanical equipment. Therefore, accurate state monitoring and fault diagnosis of rolling bearings have always been an important concern to the community. Since the vibration signals of mechanical equipment are propagated between different components, in order to comprehensively monitor the operating status of the machine and accurately locate the faults, it is necessary to simultaneously obtain vibration signal from multiple bearing measurement points. Existing vibration monitoring methods inevitably have the problems of cumbersome arrangement and high cost when facing the demand of multi-point monitoring. Here proposes a full-field bearing condition monitoring and fault diagnosis method based on millimeter-wave radar, which can give full play to the advantages of millimeter-wave radar's large field of view, multi-channel, and low cost. Based on commercial millimeter-wave radar modules, we developed a method for full-field target localization, isolation and extraction of signals of interest and phase information enhancement. We synchronously collected vibration information from multiple measurement points in the radar field of view in the validation experiments, further analyzed the bearing vibration signals, and successfully obtained a sub micron-level impulse sequence generated by a localized failure of outer ring. The work provides a potential novel method for multipoint condition monitoring and fault diagnosis of mechanical machine.