Daytime star sensor provides accurate navigation information to air vehicles flying near the ground all day long. To filter out the strong background radiation in the atmospheric environment, the daytime star sensor has been designed with multiple infrared star cameras. The new design, known as the star sensor with multiple fields of view (FOV), represents the future directions for modern star sensors. The development of the daytime star sensor requires a huge number of star maps, which can be efficiently produced by computer-aided image simulation. In light of the above, this paper proposes an image simulation method for the 3-FOV star sensor, and analyses its structure and working principle. Then, the author designed a simulation framework consisting of an observed star catalogue, an observed start calculation module, a ray tracing module, and an image output module. Specifically, the observed star catalogue was created after studying and processing the Two Micron All-Sky Survey (2MASS) star catalogue. Moreover, the entry of rays into the optical system, composed of spherical or aspherical optical surfaces, in the 3-FOV daytime star sensor was explained in details, the pixel energy on the image plane was calculated to generate the simulated star maps, and the simulation experiments were carried out to verify the feasibility of the proposed image simulation method.
Daytime star sensor, Star catalogue, Ray tracing, Observed stars, Image simulation, Aspherical surface
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