Rapid autonomous all-sky map fixed star identification method

Abstract

The invention discloses a rapid autonomous all-sky map fixed star identification method which comprises the following steps: (1), generating a navigation star diagonal pitch table according to a visual field of a star sensor; (2), sequencing all observation stars according to energy; (3), constructing an observation star triangle by using a novel triangle selection method; (4), performing triangle matching identification on the observation star triangle based on an improved K vector method; (5), if a triangle matching identification result is unique, calculating a current gesture and carrying out projection verification, if the result is not unique, performing tetrahedron identification, if a tetrahedron identification result is unique, calculating a gesture and carrying out projection verification, and if the result is not unique, re-selecting observation stars to form a tetrahedron for performing matching identification; and (6), performing projection verification on the identified unique result according to the calculated gesture, and if the projection verification is passed, indicating that the identification is successful. The rapid autonomous all-sky map fixed star identification method has the advantages of saving storage space, reducing star map identification time and increasing identification accuracy, and is great in practical value.

Description

technical field [0001] The invention relates to a star map identification method, in particular to a fast all-sky star map autonomous star identification method for a star sensor. Background technique [0002] The star map recognition algorithm is one of the core technologies of the star sensor. It can be divided into all-sky star map recognition and partial star map recognition according to whether there is coarse attitude or rough position. The corresponding working modes of star sensors generally include all-sky recognition mode and star tracking mode. Partial star map recognition needs to provide approximate attitude information to complete the identification and tracking of local sky areas. All-sky star map recognition does not require any attitude information, and completes autonomous recognition through all-sky star map comparison. The all-day star map recognition is the basis for the star sensor to realize the all-day autonomous attitude output. The recognition diff...

AI Technical Summary

Problems solved by technology

However, this method also has some defects: in the field of view where there are many bright stars with similar magnitudes, the recognition rate is seriously reduced, and it is prone to misidentification

[0009] Raster algorithm recognition has the advantages of small storage capacity, high success rate, good real-time performance and robustness, the algorithm is not sensitive to geometric measurement errors, and does not need to use star brightness features in recognition, but the main disadvantages are: After the main star is determined, the establishment of the observation mode depends entirely on the reference star. If different reference stars are selected, the established observation modes will be completely different and have no connection with each other. If the correct reference star cannot be selected, the corresponding observation mode and navigation pattern will not match

[0013] The advantages of this method are: high recognition probability, low cost of algorithm implementation, and high recognition error tolerance rate; the disadvantage is that it is necessary to select a reference star and establish a polar coordinate template based on the reference star. If the correct reference star cannot be selected, then The observation template and the navigation template will not match, and this identification method needs to establish a polar coordinate template for each navigation star in the navigation star catalog. The polar coordinate template requires a large storage space, and at the same time, the observation template needs to be matched with each navigation template, which requires a long recognition time and poor real-time performance

Among them, the triangle algorithm is simple in principle, easy to implement, and fast in recognition speed, but its recognition feature dimension is low, redundancy and mismatch are large, and the storage space required is relatively large; the polar coordinate matching method has a high recognition probability and a low false recognition rate. , but this method needs to select the reference main star. If the correct reference star cannot be selected, the recognition will fail, and the algorithm needs to create a template for each navigation star, which requires a large storage space, long recognition time, and poor real-time performance.

Although the polar coordinate matching method has a low misrecognition rate, its real-time performance is poor. For this reason, in order to realize fast recognition, the present invention absorbs the advantages of the triangle algorithm and improves its shortcomings, and proposes a fast all-day autonomous star map recognition algorithm

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