Star Identification of High Dynamic Star Sensor Under Rolling Shutter Exposure Mode

At present, it is difficult to achieve the accurate star identification of star sensor in high maneuvering state. Especially under rolling shutter exposure mode, additional rolling shutter distortion further increases the risk of failure for star identification. Therefore, a new star identification algorithm for high dynamic star sensor under rolling shutter exposure mode is proposed. The star-pair position ratio (SPR) is taken as a stable matching feature through the theoretical analysis. Then, the star identification is realized based on a way of circular voting. The experiments are carried out under low angular velocity and high angular velocity working conditions subsequently, whose results show that the proposed algorithm has better robustness to position noise, variable velocity motion, magnitude noise, and false star than the traditional algorithms. When the angular velocity is 10 degrees /s and the standard deviation of position noise is within 2 pixels, the identification rate is still higher than 94.3%. Moreover, the robustness test of this algorithm to magnitude noise and false stars shows that the identification rate is higher than 97.0% when the angular velocity is 7 degrees /s under the magnitude noise of 0.6 Mv. Also, the identification rate is still higher than 73.0% under the condition of 10 degrees /s and adding two false stars with the magnitude of 3 Mv. Finally, the validity of this method is tested by real star map. This algorithm provides a new idea for star identification in high maneuvering state and improves the dynamic performance of the star sensor under rolling shutter exposure mode to a certain extent.