【作者】 黄翀；

【导师】 陈海清；

【作者基本信息】 华中科技大学 ， 光学工程， 2011， 博士

【摘要】 该模拟器利用光机电控一体的系统仿真技术,用于在实验室内模拟真实的目标飞行场景。另外模拟器受实验室实验环境的要求,设计上受到体积、重量的限制,同时要有很好的抵抗恶劣环境性能。本论文针对某型号的模拟器展开设计研究。该模拟器模拟三种目标类型,即固定在市场中心的第一目标、可分离出视场中心的第二目标以及多个目标一维排列的第三目标组。设计方案为将辐射源进行一次成像,并在该像面设置视场光阑,通过调节该光阑的孔径大小模拟近距离的目标范围内的不同目标距离。同时,在该像点附近设置光能调制器件,通过衰减透射的光能量进行远距离范围内的目标距离的模拟。另外,利用扫描镜模拟目标分离出视场中心的场景。针对不同的目标形态所要求的视场范围,设计三条光路,并用光耦合器件耦合成一路,最后利用望远式投影镜投射至接收器的光学系统。文中分别对望远系统、望远系统后的三条成像光路、望远系统和三条光路的组合、以及扫描到最大分离视场时的光路进行像质评价和分析。结果表明,系统的光学像质满足模拟成像要求。另外还对光学系统进行了公差分析,保证系统的加工精度对像质的影响不大。推导接收器接收到的实际目标的辐射能量表达式,并提出计算模拟器辐射源辐射亮度的方法。系统利用氙灯作辐射源,实验检测该辐射源的光谱亮度分布。根据模拟器中光能转播模拟原理分别推导模拟器在近距离范围内和远距离范围内的的出射亮度表达式。系统采用红外偏振片组合作为远距离模拟的光能调制器。利用琼斯矢量法进行推导,提出了实际偏振片组合的衰光率表达式。实验证明该表达式在低衰光率时表达衰光率的精确度大大地高于马吕斯定律。利用以上算法推导三片偏振片组合的衰光率,提出了不同旋转模式下的衰光率规律。另外,进一步推导出了不同消光比的两片偏振片组合的衰光率表达式,并推广到三片以上的情况。本系统采用三片相同消光比的偏振片组合,通过旋转中间的偏振片在保证动态性能良好的前提下大幅扩展了衰光范围。根据模拟器的光学系统结构推导出不同运动组件的模拟数学模型,并由此求得元件的运动速度和加速度与目标信号变化速度和加速度的关系。根据运动件的加工误差和侍服电机的控制误差进行控制精度分析,得到不同运动情况下的模拟信号的误差分布。对模拟器的支撑板按照转台的运动参数和系统内热力参数进行热-力的耦合分析,同时进行振动环境的功率谱密度响应分析。结果表明,支撑板的形变量很小,该模拟器具有良好的可靠性。更多还原

【Abstract】 Aviation scene simulator is used in simulate a flying scene of real target in laboratory. It includes synthesis technique such as optics, mechanism, electronics and control. Simulated functions are spectrum feature, target distance, approaching velocity, approaching acceleration, visual angle, separating velocity of different targets etc. The simulator is a load of the flight table, and is limited in volume, weight. But it needs good property of anti-impact, anti-vibration and heat-resisting.This thesis is about the research of design of the simulator. Three types of target are simulated. The first is the target which is fixed in the centre of the field of view. The second target can be separated from the centre of the field. The third is a group of targets aligned in a row. Upon our design scheme, radiant source is imaging first, and the field diaphragm is located at the image place. The distance variation in near range is simulated by changing the aperture of the field diaphragm. In the mean time, a light energy modulator is settled by the image place and the distance simulation in far range is operated by attenuate the intensity of the light signal. Besides, the separating from the centre of the field is simulated by a scanning mirror.We design three optical paths for different fields of these target types. They are combined into one beam which is projected to the optical system of the receiver by a telescope projector. In this thesis, we analyzed the imaging quality of the projector, the three imaging sub-systems and the three combinations of the sub-systems and the projector, both before scanning and after scanning to the maximum. Results show that the imaging quality of optical system satisfies the requirement of the simulation. Furthermore, we analyze of the tolerance of the optical system to ensure that the manufacture error does not affect the imaging quality much.The expression of the received radiant energy of the real target is deduced, and the radiant brightness of the radiant source is demonstrated. Xenon lamp is used as the radiant source in the simulator, and the radiant brightness distribution in the spectrum is detected in experiment. The radiant brightness expression of in both near and far distance range is deduced according to the principle of light energy transmission in the simulator. Infrared polarizers combination is used as the modulator of light energy in the simulator. The attenuation ratio expression of two polarizers combination is deduced. It is verified by experiment that in low transmittance state, the expression presents a more precise extinction ratio than Malus’s Law does. Attenuation ratio of three polarizers combination is deduced according to this algorithm, and change rule of the attenuation ratio in different rotation modes. Furthermore, attenuation ratio of combination of two polarizers with different extinction ratios is deduced, and it is extended to the states of more than three pieces. In this simulator, we combine three same polarizers and rotating the middle one to enlarge attenuation range by the premise of guaranteeing its dynamic performance.Simulation mathematical model of different moving components is demonstrated based on the optical structure and parameters. Accordingly, relations between the moving velocity and acceleration of simulated target signal versus those of the moving components are demonstrated. According to the manufacture error and the control error of the servo motor, the error of the simulated moving parameters is analyzed.Analyze the response of retaining plate by modeling the both physical fields of motion of the flight table and the heat transmission in the simulator. Besides, analyze the response of the retaining plate under power spectrum density in vibrating circumstance. According to the results, deformation of the retaining plate is small so that the simulator can be regarded firm enough and reliable.更多还原