Research On High-precision Magnitude Simulation Technology Of Dynamic Star Simulator

Dynamic star simulator is a kind of ground test equipment which is mainly used to test and calibrate the function of star sensor.The dynamic star simulator can simulate the parallelism of spectral illuminance and color temperature of stars in the infinite distance,so as to test the function of star map recognition and tracking of star sensor.With the rapid development of star sensors,the dynamic star simulator are also developing towards the direction of miniaturization,high speed and more realistic star map simulation.Magnitude is one of the key parameters in star map simulation of dynamic star simulator,The simulation accuracy directly affects the overall performance of the star sensor.This paper focuses on the magnitude simulation in the dynamic star simulator to achieve high-precision simulation of the dynamic star simulator.In order to meet the high-precision simulation of the magnitude,It is required that the collimating optical system in the variable dynamic star simulator must have high image quality.Firstly the type of star map display device is determined according to the effective field of view,single pixel angle and magnitude simulation range of dynamic star simulator optical system,Then the design indexes of optical parameters such as focal length,exit pupil distance and exit pupil aperture of the optical system are determined.The collimating optical system in the dynamic star simulator of the star is designed by using the software platform of ZEMAX and the image quality of the designed optical system is analyzed.The analysis results show that the optical system has the characteristics of good imaging quality and can realize the requirements of high precision magnitude simulation of simulated star map.Aiming at the problem that magnitude information cannot be simulated in star map simulation of existing dynamic star simulators which leads to the low reliability of star sensors.A new magnitude algorithm based on multi-pixel fitting and its distribution conforming to two-dimensional Gaussian distribution dynamic star simulator is proposed.The algorithm distributes the energy of the magnitude and simulates the magnitude so that multiple magnitude points can be displayed in a dynamic star map at the same time.The simulation accuracy of magnitude in the simulated star map was tested by using weak illuminometer and CCD camera.The measured results show that the algorithm can achieve magnitude simulation of 2-6mv and the accuracy error of magnitude simulation is better than 0.1Mv which meets the high precision simulation requirements for magnitude.