Method for calibrating star sensor

Abstract

The invention relates to a method for calibrating a star sensor, which can effectively solve the problems of low calibrating speed, low efficiency and high hardware requirements of the star sensor. The method comprises the following steps of: calibrating internal parameters of the star sensor to obtain a coordinate of a mark point in a coordinate system of a photogrammetric system; carrying out image processing on a picture and calculating internal parameters of cameras; establishing a transit surveying coordinate system; carrying out measurement on a manual surveying mark of a calibrating field by using a transit surveying system to obtain a three-dimensional coordinate of the manual surveying mark in the coordinate system of the transit surveying system; carrying out common point conversion by utilizing a three-dimensional coordinate value to obtain a conversion relation of the coordinate system of the calibrating field and the coordinate system of the transit surveying system and converting the coordinate system of the transit surveying system and a cubic prism coordinate system into the coordinate system of the calibrating field; and taking a picture of the calibrating field again to obtain a relation of the two cameras and the cubic prism coordinate system. The method for calibrating the star sensor of the invention has the advantages of simple calibrating process, low required precision for the hardware, high calibrating precision and high speed, greatly improves the working efficiency and is an innovation on the calibration of the star sensor.

Description

1. Technical field [0001] The invention relates to aerospace technology, in particular to a star sensor calibration method suitable for digital photogrammetry, computer vision and other fields. 2. Background technology [0002] The star-sensitive calibration method is a calibration method specially aimed at the correction parameters of the star sensor used on the satellite. The star-sensitive calibration method includes digital image scanning, coded mark recognition, and fast matching of three-dimensional points. Calibration and accuracy verification of star sensor correction parameter model, including fast adjustment with beam method with self-calibration. [0003] The main function of the invention is to realize the calibration of the correction parameters of the small field of view star sensor. The traditional method of star sensor calibration is to use a collimator with a turntable. Traditional methods have the characteristics of slow calibration speed and high hardwar...

AI Technical Summary

Problems solved by technology

[0004] In view of the above situation, in order to overcome the defects of the prior art, the purpose of the present invention is to provide a calibration method for star sensors, which can effectively solve the problems of slow calibration speed, low efficiency and high hardware requirements for star sensors. The technical solution is to calibrate the correction parameters of the star sensor by using the control field calibration. According to the characteristics of the correction parameters of the star sensor, the star sensor is calibrated by using the inner orientation element plus the lens distortion correction of the star sensor. The steps are: 1. The method of calibrating the internal parameters of the star sensor is as follows: 1. Place the calibration field of the circular light reflection mark and the coding mark in the laboratory, measure the mark of the calibration field with a digital photogrammetry system, and obtain the mark points in the photogrammetry system. Coordinates in the coordinate system; 2. Use a star sensor to take pictures of the control field at a distance of 2.5±0.2 meters from the control field, and move the camera horizontally after each position is photographed; 3. The three-dimensional coordinates of the control points of the calibration field obtained from the above measurement , use the star sensor calibration software to process the image of the photos obtained by the star sensor, and use the beam adjustment method to calculate the internal parameters of the camera;

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