Research and implementation of on-orbit self-calibration for gyroscope of circumlunar return and reentry spacecraft

Abstract

For the problems of lightening design of auto-alignment for strapdown inertial navigation platform included non-orthogonal gyroscope, an error model of non-orthogonal gyros is established in this paper, and we propose a lightweight calibration algorithm based on least square method and a ground test verification method, which achieved high accuracy calibration on-orbit within a limited amount of computing capacity.The ground mathematic simulation and the results of test validation show that our method has the similar accuracy to extended kalman filter, but the computational complexity is much less than EKF. On this basis, we achieved synchronous fault tolerant and calibration for multi-sets, multi-systems gyros on-orbit by logic design of calibration algorithm. This algorithm has already been used successfully in actual flight of circumlunar return and reentry spacecraft of 3rd phase of China lunar exploration program, and thus achieved initial attitude alignment of two-sets of inertial navigating platforms with a high degree of accuracy.