Method for making guide star database based on output accuracy of star sensors

Abstract

The invention provides a method for making a guide star database based on output accuracy of star sensors. The method comprises the following steps: S1, subjecting a basic star database to screening of fixed stars; S2, generating the direction of an optical axis of a test sky area covering the whole celestial sphere; S3, converting the celestial system of coordinates of all the fixed stars in a field of view under the direction of the optical axis into a planar system of image plane projection; S4, dividing an image plane into n regions and arraying fixed stars in each region according to m combination modes; S5, carrying out attitude solution on each combination mode of the fixed stars and removing combination modes with great errors in an accuracy index; S6, searching for fixed stars in the whole view field of the image plane and combination modes of the fixed stars forming polygons with great errors in a mismatching accuracy index; and S7, carrying out steps S2 to S6 on each optical axis direction and combining overlapped fixed star points in each sky area so as to obtain the guide star database. According to the invention, the selection process of guide stars in each field range is optimized, so a fixed star combination eventually chosen is guaranteed to meet requirements of average distribution, and attitude calculation precision is guaranteed to be optimal.

Description

technical field [0001] The invention relates to a manufacturing method of a star sensor navigation star library, in particular to a manufacturing method of a navigation star library based on the output accuracy of a star sensor, and belongs to the technical field of aerospace measurement and control. Background technique [0002] The navigation star library is a necessary part of the star sensor, and it is also the necessary basic data for the star sensor to realize the navigation function. The navigation star library is involved in the main work of the star sensor, including all-day star map recognition, star point tracking and attitude calculation, all based on the navigation star library. [0003] At present, star sensor manufacturers at home and abroad attach great importance to the production of navigation star library, and according to the selection of different star sensor optical systems and imaging detectors, the navigation star library used by each type of star sen...

AI Technical Summary

Problems solved by technology

This method simply starts from the apparent magnitude in the basic star library, and makes the star library according to the size of the star magnitude. This will cause the star library to be incomplete, and the reliability is not considered.

[0007] 3) Orthogonal grid method is to use equal-area mapping method to project candidate navigation stars from the unit sphere onto the plane, and use non-overlapping equal-area orthogonal grids to divide them, and then select the star in each cell. The star with the lowest magnitude is used as the navigation star. The navigation star library produced by this method does not take into account the actual detection capability of the star sensor, so there will be a phenomenon that the stars in the small grid cannot be detected in practice.

[0008] 4) The regression selection method changes the fixed threshold in the magnitude threshold method into a dynamic threshold, which can effectively screen out navigation stars, but the adaptability of the dynamic threshold is still not perfect

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