Study On Reliability Test Of Shaft System Of Navigation Inter - Satellite Link Drive Mechanism

With the more applications of the Beidou navigation satellite, driving mechanism on it requires long life, high precision, high reliability. The shaft components of driving mechanism of the satellite antenna is the key component to insure the whole system normal operation, its degradation or failure will lead to failure or pointing accuracy reduction of satellite antenna. During orbit phase, millions of times intermittent reciprocating motions for the shaft components are needed. Traditional life- test methods need to take too much time and money, it is impractical, accelerated life-test have to be executed on some product samples to testify the design and the reliability of the driving mechanism. Based on this demand, the following research and development are completed in this project.The analysis for failure mode and its influencing factors of the shafting components are carried out, and a conclusion is drawn that the solid lubricating angular contact ball bearing is the critical influencing part and the most weakly point to the life of shaft assembly.The research is done on equivalence theory for accelerated life test, final decision is made that friction torque and rotation accuracy of the shaft assembly will be taken as the failure criterion.The general experimental scheme of accelerated life test of shaft assembly is made. Based on the research and analysis, the rotational speed and the pre-tightening force to the bearing are taken as the accelerating factors.To meet the demand of the accelerated life test, test equipment are designed and made. the real-time criterion data acquisition and processing can be achieved. Monitoring to the shaft assembly running condition and judgment to the failure can be carried out in real-time.Based on the accelerated life experimental data, by analyzing the functional degradation and the "false" life of the shaft assembly, the expected life is deduced, then judgment can be made if the driving mechanism meet the designing demand.Furthermore, the analysis to the expected life applied different pre-tightening force to the bearing is present in this paper, this provides a practical basis for the correct pre-tightening force application on the bearing in the shaft assembly.