摘要
为了满足精准高效快速部署航天遥感器对轻小型空间相机的迫切需求,对满足轻小型相机成像的光学系统形式及成像体制进行了详细对比分析,确定了RC+补偿组的光学系统形式,采用小F数+微小像元的成像体制。对比美国鸽子相机的详细参数,设计了500 km轨道高度上可实现3.48 m分辨率的轻小型全铝高分相机。详细介绍了相机的总体结构、光学系统、光机结构、成像电子学及热控设计结果,得到F5.6的RC+补偿组光学设计结果。采用RSA-6061微晶铝合金做为相机反射镜的结构材料,配合一体化硬铝合金高刚性结构。静力学(重力变形和温度变形)仿真分析结果满足光学设计公差要求。动力学仿真分析结果表明:一阶模态为302.92 Hz,具有足够高的动态刚度和安全裕度。成像电子学采用3.2μm大面阵9 K×7 K探测器低噪声小型化设计。相机热控由卫星平台保证20℃±4℃的温度水平。集成测试结果表明:(1)相机中心视场波像差RMS为λ/15.6,5个视场系统波像差均优于λ/12.3,可以确保相机近衍射极限高质量成像。实测奈奎斯特频率处的光学传递函数为0.217;(2)相机三方向正弦振动最大处放大1.17倍,整机一阶模态为295 Hz,与仿真结果的偏差为2.61%,相机结构刚度大,力学稳定性好;1×10^(-4)Pa,16℃、20℃、24℃三个温度工况下成像清晰,可分辨奈奎斯特频率处对应的分辨率板图像;(3)对2 km外目标成像效果良好,图像清晰且灰度层次分明,阴影边界锐利。本文所设计轻小型全铝高分相机在500 km轨道高度上实现了3.48 m分辨率,15 km×15 km幅宽,整机重量为2 kg,结构刚度和强度试验结果满足航天发射场景需要,可以为轻小型甚高分辨率空间相机设计提供理论指导和工程借鉴。
In order to meet the urgent need of developing lightweight and compact space cameras quickly,effectively,and rapidly,a detailed comparative analysis is conducted,including optical system forms and imaging systems.The optical system form of RC+compensation group is determined,and the imaging system of small F#+micropixel is adopted.Compared with the detailed parameters of the DOVE camera,a lightweight all-aluminum high-resolution camera with a resolution of 3.48 m at an orbital altitude of 500 km is designed.The overall design results of the camera,its optical and optomechanical structures,imaging electronics,and thermal control are described in detail.The optical design results of the RC+compensation group of F5.6 are obtained.Using RSA-6061 microcrystalline aluminum alloy as the structural material of the mirror,coupled with an integrated high-rigidity hard aluminum alloy structure,the static(gravity and temperature deformation)simulation analysis results meet the optical design tolerance requirements.The dynamic simulation analysis results show that the first order mode is 302.92 Hz,which has a sufficiently high dynamic stiffness and safety redundancy.The imaging electronics using a 3.2μm large area array 9 K×7 K detector is designed for low noise miniaturization.Thermal control is provided by the satellite platform at a temperature level of 20°C±4°C for the camera.Integration test results show that:(1)The RMS wave aberration of the central field of view isλ/15.6,and the wavefront aberration of the five fields of view is better thanλ/12.3,which ensure high-quality imaging near the diffraction limit of the camera.The measured optical transfer function at Nyquist frequency is 0.217;(2)The maximum sinusoidal vibration of the camera in three directions is amplified 1.17 times,and the first-order mode of the camera is 295 Hz,with a deviation of 2.61%from the simulation result.The structural stiffness is high and the mechanical stability is good.Under vacuum environment of 10^(−4) Pa and three different temperatures of 16°C,20°C and 24°C,the image is clear and can distinguish the corresponding resolution plate image at Nyquist frequency;(3)The image of 2 km outfield target is good,as well as clear and distinct grayscale image with sharp shadow boundaries.The all-aluminum high-resolution camera is achieved 3.48 m resolution at a track height of 500 km,width of 15 km×15 km and a total weight of 2 kg.The structural rigidity and strength test results meet the requirements of space launch scenarios,and these can provide theoretical guidance and engineering reference for the design of lightweight and higher-resolution space cameras.
作者
孙景旭
谢虹波
李淑贤
谢新旺
王硕
周峰
SUN Jing-xu;XIE Hong-bo;LI Shu-xian;XIE Xin-wang;WANG Shuo;ZHOU Feng(Department of Optoelectronic Science and Technology,Ji Hua Laboratory,Foshan 528200,China;No.96035 Troop,the Chinese People's Liberation Army,Jilin 132101,China)
出处
《中国光学（中英文）》
EI
CAS
CSCD
北大核心
2023年第6期1450-1462,共13页
Chinese Optics
基金
广东省重点领域研发计划资助项目(No.2018B030328001)。
关键词
轻小型
高刚性
动态刚度
低噪声
lightweight and compact size
high rigidity
dynamic stiffness
low noise
