基于改进卡方检验的星跟踪过程中的伪星检测与隔离

False star detection and isolation during star tracking based on improved chi-square tests.

作者信息

Zhang Hao, Niu Yanxiong, Lu Jiazhen, Yang Yanqiang, Su Guohua

机构信息

School of Instrumentation Science and Opto-Electronics Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191, China.

出版信息

Rev Sci Instrum. 2017 Aug;88(8):085004. doi: 10.1063/1.4998986.

DOI:10.1063/1.4998986

PMID:28863708

Abstract

The star sensor is a precise attitude measurement device for a spacecraft. Star tracking is the main and key working mode for a star sensor. However, during star tracking, false stars become an inevitable interference for star sensor applications, which may result in declined measurement accuracy. A false star detection and isolation algorithm in star tracking based on improved chi-square tests is proposed in this paper. Two estimations are established based on a Kalman filter and a priori information, respectively. The false star detection is operated through adopting the global state chi-square test in a Kalman filter. The false star isolation is achieved using a local state chi-square test. Semi-physical experiments under different trajectories with various false stars are designed for verification. Experiment results show that various false stars can be detected and isolated from navigation stars during star tracking, and the attitude measurement accuracy is hardly influenced by false stars. The proposed algorithm is proved to have an excellent performance in terms of speed, stability, and robustness.

摘要

星敏感器是航天器的一种精确姿态测量装置。星跟踪是星敏感器的主要和关键工作模式。然而，在星跟踪过程中，伪星成为星敏感器应用中不可避免的干扰因素，可能导致测量精度下降。本文提出了一种基于改进卡方检验的星跟踪中伪星检测与隔离算法。分别基于卡尔曼滤波器和先验信息建立了两种估计。通过在卡尔曼滤波器中采用全局状态卡方检验进行伪星检测。利用局部状态卡方检验实现伪星隔离。设计了在不同轨迹下带有各种伪星的半物理实验进行验证。实验结果表明，在星跟踪过程中，各种伪星能够从导航星中被检测和隔离出来，且姿态测量精度几乎不受伪星影响。结果表明，所提算法在速度、稳定性和鲁棒性方面具有优异的性能。