石英挠性加速度计测量航天器微振动的方法

Measurement of spacecraft micro-vibration based on quartz-flexibility-accelerometer

利用高精度石英挠性加速度计可以测量航天器低频微振动,同时也可实现航天器在轨微角振动的间接测量。针对航天器特点,结合石英挠性加速度计工作特性,提出用高精度石英挠性加速度计测量航天器微振动的方法,给出微振动加速度、角加速度、角速度和角位移的不确定度分析,根据测量原理给出了各影响因素对测量合成不确定度的计算方法和分析结果。针对卫星敏感载荷的刚体平面测试环境,设计8个加速度计测点布局,开展了整星试验。试验数据分析表明:石英挠性加速度计可准确测量航天器的低频微振动(200 Hz以内),其直接测量和间接测量结果满足测量应用需求,线加速度测量分辨率为5μg,角位移测量分辨率为0.015″。

The quartz-flexibility-accelerometer of high precision can be used to measure the low frequency micro-vibration of spacecraft on-orbit directly, and the micro-angle vibration indirectly. The paper makes an uncertainty analysis when the quartz-flexibility-accelerometer is applied to measure the micro-vibration acceleration, the angular acceleration, the angular velocity and the angular displacement, the calculation method is proposed and various influencing factors are analyzed for the combined measurement uncertainty based on the measurement principle. An eight accelerometer measurement point layout is designed for the entire satellite test in the rigid planar test environment for the satellite sensitive payload. Entire satellite measured data show that the quartz-flexibility-accelerometer can accurately measure spacecraft’s low frequency micro-vibration, the direct and indirect measurement results meet the need of applications, the linear acceleration measurement resolution ratio is 5 μg, and the angular displacement measurement resolution ratio is 0.015″.