突破卫星轨道和姿态参数分别确定的传统模式,提出了以三轴磁强计和太阳敏感器为测量元件的轨道姿态一体化确定算法。由于地磁场是时间和位置的函数,而三轴磁强计指向又与卫星姿态相关,所以三轴磁强计的测量值既与轨道有关,又与姿态有关。充分利用磁强计和太阳敏感器的测量值中包含的轨道和姿态信息,推导出卫星轨道姿态一体化确定的扩展卡尔曼滤波算法。在太阳不可见区域,由于太阳敏感器没有输出信息,只采用磁强计为测量敏感器,按传统模式对卫星轨道和姿态分别确定。最后对2种模式下的滤波算法进行数学仿真验证,结果表明该算法的可行性与有效性。
A new method for both orbit and attitude determination of satellite simultaneously based on three-axis-magnetometer (TAM) and sun sensor is presented, which is a breakthrough in traditional pattern of treating orbit and attitude of satellite separately. The earth magnetic field is a function of position and time, so the measured magnetic field by magnetometer fixed on the body is a function of the orbit and attitude. An extended Kalman filter algorithm for integrated orbit and attitude determination is proposed, which makes full use of the measurement. In the condition of shade of sun, only magnetometer is used, or-bit and attitude are estimated separately following the traditional pattern. Numerical simulations of the two patterns are given so as to confirm the proposed algorithm to be feasible and effective.