采用简化滤波器思想的卫星姿态确定系统故障诊断

Fault Diagnosis for Satellite Attitude System by Simplified Filter Scheme

针对星上计算机运算资源有限的问题,为了降低卫星姿态确定系统故障诊断的运算量,提出一种基于卡尔曼滤波器的故障检测与分离方法。该方法首先基于卫星姿态运动方程设计了一种加性卡尔曼滤波器,然后将卡尔曼滤波器与简化观测器思想相结合,进一步提出一种采用简化滤波器思想的姿态敏感器故障诊断律。所提出的故障诊断方法既可以实现对陀螺故障的检测与分离,又能够诊断星敏感器的故障。此外,该方法只利用一个滤波器即可实现故障检测与分离,其计算量小,有利于在轨实施。最终采用一个由三正交一斜装陀螺组件和星敏感器构成的姿态确定系统对所提出的方法进行了仿真校验,仿真结果表明了所提方法的有效性。

Considering the fact that the computation resources of an on-orbit computer are limited,this paper proposes a fault detection and isolation method based on a Kalman filter to reduce the computation load of the fault diagnosis for a satellite attitude determination system.In the proposed method,a novel additive Kalman filter is designed based on the attitude kinematics,and then a sensor fault diagnosis method is presented using the simplified filter scheme by integrating the Kalman filter with the simplified observer scheme(SOS).The proposed fault diagnosis method not only can detect and isolate the gyro fault,but also can diagnose the fault of the star sensor.In this method,only one filter is used to achieve the fault detection and isolation.Moreover,it is easy for computation and hence is useful in on-orbit implementation.The proposed method is verified by an attitude determination system consisting of a tri-orthogonal-one-slant gyro component and a star sensor.The simulation results show the effectiveness of the proposed method.