Apparatus for measuring inertia of fiber gyro composite unit and its calibration method

The invention relates to an apparatus for measuring inertia of a fiber gyro composite unit and its calibration method, and especially relates to the apparatus for measuring the inertia of the fiber gyro composite unit with miniaturization, high reliability and redundant multi-tables used for navigation, guidance and control of spacecrafts, which belongs to the inertia measurement technical field. The apparatus comprises a hexangular pyramid and a pedestal; six fiber gyroscopes are uniformly distributed on six side surfaces of the hexangular pyramid, six signal processing and interface circuits and six secondary power sources are arranged in the pedestal. According to the invention, the gravity center is positioned at a geometric center as possible, and the anti-mechanical capacity is good; the six fiber gyroscopes are redundant backup with each other; the reliability is high; in the process of in-orbit operation, a triaxial attitude angle speed can be still provided even the fault is generated by no more than three shafts at will, and the fault detection and the isolation can be realized. The calibration method can accurately calibrate zero position, scale factor and installation error, and can effectively enhance the in-orbit usage precision.