基于MME/EKF算法的卫星质心在轨标定

On-Orbit Calibration of Satellite Center of Mass Based on MME/EKF Algorithm

提出了一种基于MME/EKF的卫星质心在轨标定算法。首先以磁力矩器为执行元件给卫星施加一个明显大于干扰力矩的周期性力矩,将静电加速度计的量测信息分解为线性和周期性加速度,并将星敏感器标定后的陀螺仪数据代入MME算法中估计出卫星的角加速度,然后利用EKF算法求解卫星质心的位置。最后进行了数学仿真验证,仿真结果表明该算法不需要卫星的控制输入以及动力学特性信息,便能实现卫星质心较为精确的标定。

A method for on-orbit calibration of satellite center of mass based on MME/EKF estimation algorithm is proposed in this paper.The proposed method is embodied into three steps.First,the observation of a electrostatic accelerometer is decomposed into linear and periodic accelerations while a periodic magnetic torque which is more larger than other external torques is applied on satellite.Second,the observation of gyro calibrated by star sensor is used to estimate angular acceleration based on MME.Third,EKF is used to estimate the center of mass of satellite.The calibration accuracy can be ensured by using this method if the contol input and attitude dynamic information of satellite are unkown.The Numerical simulations have demonstrated the effectiveness of the proposed method.