Accuracy Measurement System for Star Sensor

Abstract

The invention discloses an accuracy measurement system for a star sensor. The accuracy measurement system comprises a fixer and a star sensor accuracy measurement unit, wherein the fixer is used for fixing the star sensor to make a main shaft of the star sensor aligned with a zenith; the star sensor accuracy measurement unit is used for measuring the accuracy of a navigation star; a test startingmoment T is input into the star sensor; a direction vector under a J2000.0 rectangular coordinate system is determined according to declination, right ascension and apparent motion parameters of the navigation star under a J2000.0 coordinate system; the direction vector is converted into the direction vector under an epoch ecliptic coordinate system and then converted into a direction vector (VCRFT) under a celestial sphere coordinate system; the direction vector of the navigation star under the celestial sphere coordinate system is changed into a direction vector (VTRF) under an earth-fixed coordinate system; and based on the direction vector (VTRF) under the earth-fixed coordinate system, the accuracy of the star sensor is obtained. According to the accuracy measurement system provided by the invention, the star sensor is fixedly connected to the earth by using the accuracy of rotation of the earth, and the main shaft of the star sensor is aligned with the zenith for observation.

Description

technical field [0001] The invention belongs to the technical field of attitude sensors, in particular to an accuracy test system for star sensors. Background technique [0002] With the advantages of high precision, low power consumption, and small size, star sensors have become the most competitive attitude-sensing devices for spacecraft. At present, the attitude determination accuracy of star sensors can reach 10″, and the accuracy of some types of star sensors can even reach 1″ level. High precision is the key factor for the rapid development and wide application of star sensors. With the increasing precision of star sensors, higher requirements are put forward for precision measurement methods. Traditional test methods are mainly based on star simulators and precision turntables. The position accuracy of turntables needs to be an order of magnitude higher than that of star sensors, that is, to reach the sub-arcsecond level. This kind of equipment is expensive and the o...

AI Technical Summary

Problems solved by technology

Traditional testing methods are mainly based on star simulators and precision turntables. The position accuracy of the turntable needs to be an order of magnitude higher than the measurement accuracy of the star sensor, that is, to reach the sub-arc second level. This kind of equipment is expensive and the operation process is complicated.

At the same time, when the laboratory calibrates the turntable, the star simulator is used as the measurement benchmark, but it is very difficult to realize the all-sky star simulator that meets the requirements of spectral range, magnitude and position accuracy. There is a large gap, and the real starry sky cannot be completely simulated, making it difficult for people to be convinced of the authenticity and accuracy of laboratory tests.

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