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The star tracker should be accurately calibrated in order to achieve high precision. The calibration procedure can be well performed in the laboratory with the aids of a high-precision two-axis rotary table. Hence, the calibration accuracy is heavily relied on the performance of the rotary table. In this paper, use a collimator to emit starlight, then the influence of the rotary table error on the calibration result of the star tracker is analyzed in detail. The simulation and experimental results show that the accuracy of the rotary table has a great influence on the laboratory calibration results. When the rotary table error is 2 '' Gaussian error, the attitude angle calibration error is within 3 '' . The intrinsic parameters calibration accuracy are as follows, the principal point error is within 5 pixels, the focal length error is 0.001mm, less than 20% deviation of tangential distortion, radial distortion within 120% deviation. Except the declination error and the fixed angle along the optical axis error is within 5 '' , the remaining extrinsic parameters have relatively large errors, but they have limited influence on the calibration results, for the star tracker calibration only focuses on the accuracy of the intrinsic parameters. The reprojection error of the star centroid is in a few hundredths of a pixel, and the corresponding angle error is 3 ''~5 '' , which can satisfy the high-precision attitude measurement of the star tracker.
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