静电悬浮加速度计在轨质心位置的最小二乘估计

本文使用国内首次搭载飞行的静电悬浮加速度计在轨数据与卫星姿态数据，对加速度计与卫星质心的相对位置进行了估计测量.文中分析得到，在卫星姿态机动时，加速度计的输入加速度主要来自于离心加速度及角加速度引入的线加速度.结合卫星姿态机动时陀螺仪的测量数据，使用最小二乘法对加速度计质心位置的三个分量进行了联合估计.结果表明：质心位置的估计精度达到约6 mm水平，主要受限于卫星平台条件和加速度计测量精度限制.利用本文方法对未来重力卫星任务进行了分析，若使用精度为1×10^-10 m·s^-2加速度计以及2角秒分辨率的星敏感器，可将质心位置估计精度提高至4.6×10^-6 m水平.

Least squares estimation of in-orbit mass center position of the electrostatic accelerometer

This paper utilizes in-orbit data of the firstly launched electrostatic suspended accelerometer in China and satellite attitude data to make an estimation of the relative distance between the Center-of-Mass (CoM) of the accelerometer and the satellite. It is deduced that during the attitude maneuvering of the satellite, the input of the accelerometer is mainly the centrifugal acceleration and the linear acceleration induced from angular motion.Combining gyroscope data during the attitude maneuvering, using a least squares estimation method, the three coordinate components of the accelerometer CoM position with respect to the spacecraft are jointly estimated. The analysis results show that the precision of the CoM position estimation achieves about 6 mm, which is mainly limited by the satellite platform conditions and the accelerometer precision. Based on the method in this paper, the precision for the future gravity measurement satellite mission can be improved to a level of 4.6×10^-6 m by using an accelerometer with a precision of 1×10^-10 m·s^-2 and a star sensor with a precision of 2 arc second.