静电加速度计悬浮质量块质心偏移量在轨标定

高精度静电加速度计已广泛地应用于航天任务中，用于测量作用于航天器的非引力加速度。如果静电加速度计悬浮质量块的质心与航天器的质心安装有偏差时，重力梯度力、姿态耦合产生的干扰加速度，静电加速度计控制系统引入的干扰加速度等干扰力会夹杂在测量数据中。针对这一问题，研究了航天器小质量特性变化情况下，当静电加速度计处于动态设计良好并进入稳态后，利用静电加速度计、陀螺仪和磁强计作为敏感元件，基于非线性卡尔曼滤波理论的静电加速度计悬浮质量块质心偏移量的在轨标定。仿真结果表明，该方案的精度J向可以达到0．1mm，Y和Z向能达到0．04mm。

On-orbit calibration of proof mass center offset for electrostatic accelerometer

The electrostatic accelerometer can be used to measure the non-gravity accelerations acting on spacecraft. If the proof mass center is not positioned at the center of mass of spacecraft,the gravity gradient and some interference accelerations and the interference force control would be involved in the measured result. In view of this problem,the paper studied the on-orbit calibration of proof mass center offset when spacecraft was in the situation of little mass variety and the electrostatic accelerometer was in good dynamic and steady sate. The calibration was based on non-linear Kalman filter and used electrostatic accelerometer,gyro and magnetometer as measuring sensors. The associated simulation shows that the accuracy could be 0.1 mm along X axis,and 0.04 mm along Y and Z axis.