摘要
研究了机载成像系统的像移及其对成像质量与相机分辨率的影响。为准确获取像移矢量,实现成像系统像移补偿,提出了一种基于坐标变换的机载成像系统像移计算模型。通过线性坐标变换,建立了从地面目标景物到成像系统像面的坐标变换模型,推导了地面目标景物在成像系统像面的解析表达式,根据坐标在相机积分时间内的变化来确定像移矢量。分析了成像系统像移误差的主要来源,讨论了载机轨道坐标、飞行姿态角和相机视轴角误差对像移计算结果的影响,采用蒙特卡罗方法分析和统计了像移计算误差。样本实验结果表明,在载机姿态角和相机摆角不变条件下,像移量与载机速度成正比,与目标距离成反比,像移误差随着参数误差的增加而增加,其中载机经度和纬度误差是影响像移计算误差的重要因素。结果显示本文方法对机载成像系统的像移补偿具有实用价值。
The image motion of an aerial imaging system was researched and its effects on imaging quality and the resolution of the camera were analyzed. In order to obtain and compensate the image motion of the aerial imaging system, a computation model of image motion based on coordinate trans- formation was proposed. The coordinate transformation model from a ground object to a sensor plane was established by using linear coordinate transformation, and the computation formula of image mo- tion was derived based on the different coordinates of the same ground object during camera exposure. The sources of image shift error of the imaging system were analyzed and the influences of various er- ror factors including the aircraft motion, attitude angle and the camera swing angle on image shift cal- culation were discussed. Then, the calculation error budget and synthesis with Mont Carlo method was presented. The experimental result shows that the image motion is directly proportional to the ve-locity of aircraft, and inversely proportional to the distance between aircraft and ground object when the attitude angle and camera swing angle are constant. Furthermore, the calculation error becomes greater with the increase of the parameter disturbance, especially the measuring errors of aircraft mo- tion in longitude and latitude. It concludes that this method is efficient and will be useful to the image motion compensation of aerial imaging systems.
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2012年第11期2492-2499,共8页
Optics and Precision Engineering
基金
国家973重点基础研究发展计划资助项目(No.2009CB72400607)
国防预研基金资助项目(No.402070301)
国家863高技术研究发展计划资助项目(No.2008AA121803)
关键词
机载成像系统
像移
载机运动
载机姿态角
相机视轴角
蒙特卡罗法
aerial imaging system
image motion
aircraft motion
aircraft attitude angle
camera swing angle
Monto Carlo method
