Basic problems and test verification of micro-vibration test in vacuum tank

The disturbance sources of the spacecraft ground micro-vibration test, including both the structural transmission part and the air transmission part, are obviously different from the real disturbance sources. The micro-vibration test in vacuum tank avoids the disturbance caused by air propagation and is an alternative way for high performance spacecraft to conduct ground micro-vibration test. In this paper, the analysis of test data shows that under the condition of good vibration isolation of spacecraft, the disturbance caused by noise on spacecraft is obvious. In such cases, the response caused by airborne noise should be considered. In this paper, a series of verification tests are designed to give the environmental level of microvibration in conventional vacuum tanks, and through data analysis, the degree of vacuum to eliminate the influence of acoustic vibration in such vacuum tanks is proposed. Based on the above test results, this paper discusses how to isolate the vibration of the existing vacuum tank facilities and how to apply the existing in-orbit free boundary condition simulation device in vacuum tank to meet the demand of micro-vibration test.