Research on the Algorithm of Satellite On-orbit Calibration Based on GPS/Gyro

Drift errors of the gyro can't be measured on-orbit and have been greatly impacted by the space environment under the flying condition in the space. A new on-orbit calibration algorithm is proposed to correct the drift errors of the gyro based on GPS in this paper. Firstly, the exact mathematical model of the gyro is built by error analysis. Then the error model is linearized under reasonable condition, and the state equation of system is educed in detail. The information of attitude quaternion measured by GPS in real time is used to calibrate the installation errors and the calibration errors based on the extended Kalman filter. The numerical simulation results show that the new method not only improves the navigation precision and longevity of gyro effectively but also provides better reliability and adaptability