Stellar Guidance and Positioning Method of Near Space Vehicle Based on Refraction Distribution Model

This article focuses on the stellar guidance and autonomous celestial navigation for near space vehicle by the atmospheric refraction effect. To overcome the deficiency of the traditional starlight refraction method, a refraction distribution model, including a refraction angle distribution function and isolines of refraction angles, is established by the atmospheric laws and numerical methods in the refracted starlight coordinate frame. Based on the refraction distribution model, the stellar guidance law is designed for optimal refraction observation. Then, combined with the relative attitude of the vehicle, the rotation control law of star sensors can be determined. On all these bases, three schemes with five various intersection positioning methods of the hypersonic waverider and static aerostat in the refraction distribution model are proposed. The simulation results indicate that the precise absolute attitude and refraction plane orientation are crucial to ensure the positional accuracy.