卫星姿态的鲁棒反馈滤波器方法研究

Research of Feedback Robust Filter for Satellite Attitude Determination

针对传统卫星姿态估计过程中计算量大的问题,提出了基于控制反馈的卫星姿态鲁棒滤波方法,将滤波器的新息作为闭环系统的输入,由此可以分离动态滤波方程中的时变因素(卫星姿态角速度),再将时变因素作为系统的不确定性考虑,最终通过鲁棒滤波方法对线性时不变系统的最终稳态值进行求解。该方法可以通过陀螺与星敏感器的参数信息,提前离线计算出滤波器的相关参数,具有很强的工程可用性。仿真结果表明,在卫星存在旋转角速度时,三轴的估计精度(MSE)比不考虑系统时变因素的控制反馈滤波器分别提升了12%,21.05%,4%。

In order to solve the computational burden in traditional satellite attitude estimation,an robust filter based on the feedback control filter theory is designed for the satellite attitude determination.This approach is based on feedback control,and by using the innovation information as the input of the closed-loop system,the time-varying element(satellite anglular velocity)in the dynamic filtering equation can be decoupled.Then,the time-varying element is treated as system uncertainty,and the system is evolved into an LTI(Linear Time-Invariant)system.Finally,the filter parameters can be derived by using linear discrete robust theory.These parameters can be calculated off-line in advance and this approach has sigfinicant engineering capability.The simulation results show that this approach can improve the estimation performance in terms of MSE by 12%,21.05%and 4%for the three axis of the attitude by comparing to the feedback control filter without consideration of satellite angle velocity.