Method of Estimating Star Sensor Attitude Angle Deviation Based on Star Position Error

When the traditional arctangent method is used to estimate the attitude deviation of the star sensor, there are problems such as the large amount of calculation that affects the real-time performance of the algorithm. Aiming at these problems, a new method that directly estimates the star sensor attitude angle deviation via the star position error was proposed in this study. The mathematical relationship between the star sensor attitude angle deviation and the star position was deduced based on the measurement theory of star sensor. Furthermore, in the condition of small field of view, the simplified quantitative formula between the star sensor attitude angle deviation and the star position was obtained. The simulation results indicated that the calculation speed of the proposed method was 25% faster than that of traditional method. Besides, the calculation accuracy of the new method was greater than traditional method. Theoretical derivation and simulation experiments demonstrated that the proposed method owned advantages such as small amount of calculation, good real-time performance and high precision, indicating the proposed method had certain engineering application value.

This article is based on the attitude measurement principle of star sensors and derives a mathematical formula for the influence of the attitude angle change of star sensors on the position of star images. On this basis, a method for estimating the attitude angle deviation of star sensors based on star image position error was obtained, and a simplified formula for estimating the attitude angle deviation of star sensors based on star image position error was further obtained under small field of view conditions, which is suitable for engineering practice. Compared to the traditional arctangent method, this method does not require arctangent operation, ensuring accuracy while significantly reducing computational complexity. It has certain theoretical reference significance and engineering practice value.