The Design Of Source Infrared Target Simulator

With the development of modern military technology, the infrared tracking guidance has become a tendence of high-speed and accurate aerocraft. Through the wide application of this technology, many countries had begun to develop infrared hardware-in-the-loop simulation techniques. Infrared target simulation systems can be used in laboratory to test the missiles'tracking, recognizing and attacking capabilities to target. Using infrared target simulation systems can save plenty of money and gain the missiles'work status in different conditions.The core of the system is infrared target simulator. Point source infrared target simulator is researched which can be used in hardware-in-the-loop systems.To ensure the exit pupil of collimated optical system and the entrance pupil of guidance system coincident, the distance between exit pupil of collimated system and the last surface of optical system is up to 1200mm. This increases the difficulty of the optical system design. The design methods for determining structure type of optical system and several issues needed to be considered when design an optical system is discussed. A collimated optical system is designed with optical design software CODE V and corresponding evaluation of image quality and the tolerance analysis are carried out. The structure of optical system is compact and its performance meets the requirements.The target can be found only when the illumination on the exit pupil of collimated system reaches the sensitive threshold of seeker detector. Upon the optical system is designed, illumination depends on temperature of blackbody. So it is necessary to determine temperature range of blackbody. According to the range of illumination, the dynamic temperature range of blackbody is determined. According to the results of optical design, combining given layout structure, effective radiation aperture size of the blackbody is determined, finally the parameters of blackbody are confirmed.The principle of simulating moving target at close range (≤1500m) using stop target is analyzed, and the expression between distance and caliber of stop target is derived. Screw-driven opening program is selected as the formation of far target device and relevant calculations are made. When target moves faraway (1500m~5000m), polarized attenuator is used to simulate long-range moving target. A mathematical model is founded between distance (from missile to target) and rotational angle of attenuator. The worm-driven system is designed which controlls rotation of attenuator. The control theory of target's movement driven by stepper motor and ball screw is analyzed. Then, the suitable ball screw is chosen and parameters of stepper motor (such as step angle, static torque, etc.) are calculated. Finally, the error of simulator and fixing requirements are analyzed.Through the research, a reasonable infrared target simulator of point source is designed. The equipment can provide some reference to emulational facility which will be used to test missiles in the future.