Attitude-correlated frames approach for a star sensor to improve attitude accuracy under highly dynamic conditions

Abstract

The attitude accuracy of a star sensor decreases rapidly when star images become motion-blurred under dynamic conditions. Existing techniques concentrate on a single frame of star images to solve this problem and improvements are obtained to a certain extent. An attitude-correlated frames (ACF) approach, which concentrates on the features of the attitude transforms of the adjacent star image frames, is proposed to improve upon the existing techniques. The attitude transforms between different star image frames are measured by the strap-down gyro unit precisely. With the ACF method, a much larger star image frame is obtained through the combination of adjacent frames. As a result, the degradation of attitude accuracy caused by motion-blurring are compensated for. The improvement of the attitude accuracy is approximately proportional to the square root of the number of correlated star image frames. Simulations and experimental results indicate that the ACF approach is effective in removing random noises and improving the attitude determination accuracy of the star sensor under highly dynamic conditions.

Catadioptric Optical System Design of 15-Magnitude Star Sensor with Large Entrance Pupil Diameter

“…The optical system is one of the core components of star sensors, and its imaging quality directly affects the detection ability of the star sensors for star detection, which in turn affects the attitude control accuracy of the aerospace vehicle [ 1 , 2 , 3 , 4 , 5 ]. To improve the detection ability of the star sensor, the optical systems should have a larger entrance pupil diameter and a wider spectral range, and the distortion and chromatic aberration generated during the imaging process should be minimized.…”

Star Image Prediction and Restoration under Dynamic Conditions

“…Therefore, only by solving the frame loss and blurring problem of the star image, can the star sensor maintain good performance under dynamic conditions. Because gyroscopes have a relatively high measurement accuracy and excellent dynamic performance in a short period, using the gyroscope to assist in improving the dynamic performance of the star sensor has become a hot topic [4,5,6,7,8,9].…”

Plume Noise Suppression Algorithm for Missile-Borne Star Sensor Based on Star Point Shape and Angular Distance between Stars

“…Li et al proposed a novel guide star catalog generation algorithm [9], which is not a star identification algorithm, but provides reliable and efficient performance for the star sensor. Some algorithms [10,11] use multi-frames processing to improve robustness, but the identification time cannot meet the real-time requirements. Vincenzo Schiattarella et al proposed a multi-poles algorithm [12], which is quite robust to spurious targets but has poor dynamic performance.…”