【作者】 杨欢；

【导师】 傅山；

【作者基本信息】 上海交通大学 ， 控制理论与控制工程， 2009， 硕士

【摘要】 高速导弹在大气层内飞行时,其光学头罩与大气之间发生剧烈的相互作用,头罩周围的气体密度发生变化,由于流场的气体折射率变化使机载光学寻的器的光学成像系统中的目标像的像差急剧增加如畸变、偏移、模糊和跳动等,称为气动光学效应。气动光学效应的存在将大大降低导引头识别、跟踪目标的能力,定量地计算气动光学效应的影响,并采取有效的方法补偿、校正这种影响,成为高速导弹研制的关键课题之一。现有的校正算法研究,都只针对图像进行,而并未将流场情况考虑在内。本文提出利用光线追迹法,追踪光线受气动光学效应影响在流场中的传输过程,进而得到实际成像与标准成像之间的误差,在流场数据与所成图像之间建立联系,为图像校正工作提供参考。文章介绍了影响气体折射率的因素、光线传播的原理;气动光学仿真的方法以及光线追迹理论;作为文章重点,对仿真算法的具体实现做出说明;最后给出了仿真实验结果,证明这是一种行之有效的方法。更多还原

【Abstract】 When an otherwise collimated, coherent beam of light encountered a turbulent flow field that included index-of-refraction fluctuations, its optical wave front became aberrated, causing the beam to be degraded. The interaction of light with fluid was termed "Aero-Optics."As a result of aero-optical effects, the infrared image captured by the guide head of a hypersonic missile would be degraded, which would lead to inaccurate guidance. Calculating the aero-optical effects on infrared images and finding a method to eliminate the effects became a very important problem in hypersonic missile design. To solve this problem, a method of simulation using ray-tracing technology was presented in this paper. With flow field known, the transforming path of every ray in the flow field could be calculated, and the degraded image could be simulated. This paper introduced light transform theory, aero-optical simulation methods and the realization of the simulation program, which was the most important part. Finally some simulation results were given, which showed the simulation program was correct and useful.更多还原