卫星在轨运行期间,采用反作用轮进行姿态控制及推力器进行位置保持,星体惯量会发生改变并存在控制力矩.提出了一种基于运动学方程的矢量观测算法应用于陀螺故障诊断,采用广义罗德里格参数描述卫星姿态,避免了四元数存计算过程中出现模值不为一的情况;计算过程中采用四元数进行姿态运动学计算,避免了广义罗格里德参数复杂的积分运算.针对陀螺突变和缓变两种故障,分别在角速度幅值变化很小和幅值缓慢减小两类情况下进行仿真.仿真结果表明,该算法可有效估计星体角速度,在上述两类情况下均能准确地对突变和缓变故障进行诊断,不受星体惯量变化和控制力矩的影响,并且计算量较小,对工程应用具有较好的参考价值. During the orbit of the satellite, attitude control and position control of thrusters are used to control the attitude inertia of the satellite and the control moment exists.A vector observing algorithm based on kinematic equations is proposed for gyro fault diagnosis, The Degrees parameter describes the attitude of the satellite, which avoids the situation that the value of the modulus is not unity during the calculation of the quaternion; the quaternion is used in the calculation process to calculate the attitude kinematics, which avoids the complicated integral operation of the generalized Logarithm parameter Two kinds of gyroscope abrupt changes and gradual changes are respectively simulated under the condition of small change of angular velocity and slowly decreasing amplitude.The simulation results show that the algorithm can effectively estimate the angular velocity of the astral body, both of which It can accurately diagnose the sudden change and slow change fault, not affected by the change of the inertia of the star body and the control moment, and the calculation amount is small, so it has a good reference value for engineering application.