中国空间科学技术

中国空间科学技术 ›› 2024, Vol. 44 ›› Issue (4): 20-28.doi: 10.16708/j.cnki.1000-758X.2024.0054

• 智能航天器专栏 • 上一篇    下一篇

基于LS-SVM的精确星光折射导航观测模型

YAN Xu，WANG Dingjie，ZHANG Hongbo，YANG Hang，BAO Weimin   

  1. 1.国防科技大学 空天科学学院，长沙410073
    2.中国航天科技集团有限公司，北京100048
  • 出版日期:2024-08-25 发布日期:2024-07-26

Precise starlight refraction navigation observation model based on LS-SVM

  1. 1.College of Aerospace Science and Engineering，National University of Defense Technology，Changsha 410073，China
    2.China Aerospace Science and Technology Corporation，Beijing 100048，China
  • Published:2024-08-25 Online:2024-07-26

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摘要： 星光折射自主导航系统的精度受到星光折射观测模型的限制。针对星光折射计算简化与大气参数随高度变化对星光折射观测模型的影响，提出一种基于最小二乘支持向量机（LS-SVM）的精确星光折射导航观测模型建立方法。首先通过光线追迹高精度模拟星光折射的过程，未对折射角计算进行简化，考虑大气参数随高度的变化，得到折射真高度与折射角的非线性映射关系。然后利用LS-SVM机器学习算法精确拟合折射真高度与折射角的关系，建立关于折射视高度的高精度星光折射导航观测模型。仿真结果表明，建立的精确星光折射导航观测模型精度较高，平均绝对误差为0.986m。将该观测模型应用到星光导航系统中，导航精度较高，定位误差平均为130.7m，平均速度误差为0.1479m/s，证明了建模方法的有效性，对于星光折射自主导航的高精度研究具有一定意义。

关键词: 星光折射导航, 观测模型, 光线追迹, LS-SVM, 机器学习

Abstract: The precise observation model for stellar refraction navigation using the least squares support vector machine（LS-SVM）is introduced.The process involves high fidelity simulations of stellar refraction via ray tracing，considering changes of atmospheric parameters with altitude，to determine the nonlinear mapping between true altitude and refraction angle.The LS-SVM algorithm is applied to fit this relationship accurately，creating a precise model for refracted apparent height.Simulations show the model achieves high precision，with an average absolute error of 0.986m.When integrated into a stellar navigation system，it significantly enhances navigation accuracy，reducing the average positioning error to 130.7m and velocity error to 0.1479m/s，thereby validating the effectiveness of the modeling approach.This approach is significant for the high-precision study of autonomous navigation using stellar refraction.

Key words: stellar refraction navigation, observation model, ray tracing, LS-SVM, machine learning