The Research Of Star Map Identification Based On Compound-Eye Structure

The star sensor is an attitude system for space aircraft, it has the advantages of high precision, high speed, intelligence, no accumulated error and so on. The star map identification algorithm is one of the core technologies of star sensor, it extracts the information of stellar magnitudes, angular distance of stars from observed star map shoot by the CCD or COMS of star sensor, and then matches them with the internal star catalog to identify the observed stars, and further ascertain the attitude of the spacecraft.On the basis of summarizing the development research of the star sensor, the thesis research into the establishing process of guide star database and the matching strategy. Especially, this thesis designed a model of star sensor based on compound structure and proposed a star map identification algorithm based on the model, the algorithm improved the accuracy of star sensor and provided valuable reference for researching of star sensor. A star map identification based on compound eye structure has characteristics by the following:(1)By researching on the star sensor based on compound eye structure which buildup a large field of view with multiple high spatial resolution small field view, so it can capture more observed stars, and the observed star map has more characteristics, accordingly, the accuracy of star sensor has been improved(2)The star sensor based on compound eye structure satisfies with different star map identification algorithms when using less bright stars which are easy to identify.(3)As there is a certain angle between two small eyes, the observed stars from different eyes can buildup a big angular distance, so the thesis designed a star map identification based on compound eye structure star sensor made use of big angular distance to improve the accuracy of the star sensor.(4)Traditional single view star sensor has the problem of inconsistent three-axis accuracy (Roll accuracy far below the pitch, yaw accuracy), the small eyes of the star sensor based on compound-eye structure are perpendicular, so it can improve the roll accuracy and make them the same order of magnitude.