静电加速度计标度因数和零偏误差标定

Scale factor and bias calibration of electrostatic accelerometer

为了确保静电加速度计长期在轨工作,结合非线性Batch估计算法,研究了静电加速度计标度因数和零偏误差标定。首先,充分考虑静电加速度计量测过程中可能出现的各种误差源并进行分析,建立了静电加速度计在动态设计良好并进入稳态后,卫星姿态稳定度优于0.01°/s,卫星质心保持精度优于2mm的情况下的量测模型。然后,将高精度地球引力场模型和静电加速度计量测数据代入非线性Batch估计算法的的动力学方程中,将GPS量测数据代入非线性Batch估计算法的量测方程中,建立了静电加速度计标定因数和零偏误差标定模型。最后,通过数学仿真验证了该方法的可行性,其标定精度可达到0.2%,具有一定工程应用参考价值。

In order to ensure long-term on-orbit working of electrostatic accelerometer, its scale factor and bias calibration based on nonlinear Batch algorithm were studied. First, the possible error source of electrostatic accelerometer was considered and analyzed. Meanwhile, the observation model of electrostatic accelerometer was obtained, and after it was in good dynamic and steady state, the satellite attitude accuracy was better than 0.01°/s and the precision of satellite＇s mass center could be maintained at below 2mm. Then, the accurate gravitational model and the measurements of electrostatic accelerometer were fitted into GPS-based nonlinear Batch algorithm. Therefore, its scale factor and bias calibration model was established. At last, the associated simulation was performed to testify the availability and feasibility of the proposed calibration algorithm. The calibration accuracy could be 0.2%. This study could be used as theoretical basis for real project.