Research on Reliability Identification and Fault Diagnosis Technology of Space Bearings

In the process of using space bearing, there are some problems such as the difficulty in identifying reliability characteristics, and the lack of fault diagnosis methods. Firstly, based on the reliability enhancement test principle, the temperature stress step test under standard atmospheric pressure and the vacuum degree step test at the use temperature are designed, and a space bearing test system that meets the control and measurement requirements is constructed. Then, after collection of the vibration response data under the condition of 0r/min and 1000r/min rotation speed, the wavelet energy spectrum of time-frequency data, which is the reliability characteristics, are identified using EEMD algorithm for data fusion and de-noising to study the fault state that reliability characteristics change with stress. Next, with the vibration response data of different running moments, data fusion de-noising and amplitude feature extraction are carried based on Hilbert transform. By obtaining the energy distribution of amplitude features in different frequency segments by fast Fourier transform, which is the reliability characteristic, the fault state of reliability characteristics over time is studied. Finally, through the simulation analysis, the mechanism and law of the corresponding fault state are identified, and the diagnostic relationship between the fault state and the simulation mechanism identified by the test is established, which can provide support to the on-orbit health monitoring and fault management.