A Novel Deep Integrated Mode of SNS/Star Sensor Integrated Navigation System for Space Crafts

摘要

Star image recognition of star sensor is widely used in integrated navigation system of space crafts. In practical engineering, the two widely applied navigation modes which combine star senor and strap down inertial navigation system are simple integration and shallow integration. Compared with these two modes, deep integration mode can not only enhance the accuracy of strap-down inertial navigation system via star recognition, but it can also adopt strap-down inertial navigation system to improve the attitude accuracy output by the star sensor. However, deep integration mode is relatively more complicated and difficult to realize. An approach to realizing switchable deep integration mode is proposed. The measurement difference between SINS and star sensor is transformed and the result is used to renew the correction matrix, which is input to the star sensor to improve its output accuracy. A detailed engineering case is designed to validate the effectiveness of the approach. Simulation in the engineering case indicates that the proposed deep integration provides less estimated position, speed and attitude error and faster convergence speed than simple and shallow integration.