基于星体角速度估计的陀螺故障诊断

Fault Diagnosis of Gyroscope Based on Estimated Angular Rate

为在星载惯性基准单元(IMU)正常工作的陀螺的冗余度不满足奇偶方程法条件时诊断陀螺故障,通过卫星稳态运行期间高精度星敏感器输出的姿态四元数信息,根据卫星姿态运动学和动力学方程,采用非线性广义卡尔曼滤波(EKF)得到星体角速度的估计值。在此基础上,通过设计的故障诊断器对陀螺故障进行定位。仿真结果表明,该法可检测陀螺的突变和缓变故障。

To diagnose the gyro fault when the redundancy of the gyro in inertial measuring unit could not meet the requirement of odd-even equation, the nonlinear extended Kalman filter was adopted to gain the estimated angular rate according to the kinematic and dynamic equations of satellite attitude and attitude quaternion output from the high accuracy star sensor during the satellite running in stable state. On the basis of this, the gyro fault could be located by the fault diagnosing unit designed. The simulation results showed that this method could diagnose both abrupt and slow change fault of gyro.