星敏感器遮光罩检测技术研究(特邀)  

Research on baffle detection technology for star sensor(invited)

作　　者：杜伟峰 王燕清 姜丽辉 毛晓楠 陈楠 Du Weifeng;Wang Yanqing;Jiang Lihui;Mao Xiaonan;Chen Nan(Shanghai Institute of Spaceflight Control Technology,Shanghai 201109,China)

机构地区：[1]上海航天控制技术研究所,上海201109

出　　处：《红外与激光工程》2023年第9期47-57,共11页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(62005158)。

摘　　要：星敏感器在轨工作期间周期性地受到以太阳光为主要来源的杂散光干扰,导致恒星或感知目标捕获失效,轻者姿态数据无效,重者面临被非合作目标定向攻击。在杂散光抑制过程中,遮光罩可将太阳光消减至10-5~10-6量级,从而有效减少太阳光对像面的污染。然而,在遮光罩研制过程中,因散射模型精度不高、挡光环刃口厚度无法有效测量,导致实际遮光罩消光性能达不到预期设计要求。文中在粗糙度为1.0μm铝合金基材上测量Magic black消光涂层,并拟合出偏差小于10%的散射模型;针对挡光环刃口的特殊构造,提出利用同轴远心光路检测刃口厚度,检测精度优于1.2μm;最后以遮光罩消光比定量测试以及外场杂散光观星测试考核遮光罩杂散光抑制性能。结果表明,用拟合后的BRDF散射模型,比朗伯散射体精度提升40%;刃口检测可保障遮光罩消光性能,使得遮光罩消光比理论仿真与实际测试偏差小于12%;暗室杂散光测试使得在24°太阳光入射时像面平均灰度为55.80;外场观星杂散光测试时精度变化量不超过0.5″。该星敏感器遮光罩检测方法可为其他光电类敏感器提供理论基础与技术支持。Objective Star sensor are mainly used to achieve star attitude and perceive non-cooperative targets.When the equivalent magnitude of a constant star or non-cooperative target is large,the detection and capture of stars or sensing targets will cease to be effective due to the influence of stray light.Therefore,the suppression performance of stray light is a key technical indicator of situational awareness sensors.Engineering experience has shown that a first-order sunshade can reduce sunlight to 10-5-10-6,effectively reducing sunlight pollution on the detector image surface and improving the probability of target capture.In the design stage of the baffle,the scattering characteristics of the extinction coating on the inner surface of the baffle are often modeled as Lambert bodies,resulting in significant differences between the actual and expected values of the extinction performance;During the processing stage of the light retaining ring,the thickness of the cutting edge is often ignored,resulting in significant differences between the actual and expected values of the extinction performance of the light retaining ring.Methods To solve the technical problem of projects mentioned above,this article conducts theoretical and engineering research from two technical approaches of measurement and modeling of BRDF,and cutting edge thickness measurement.Firstly,based on the commonly used fitting formula of BRDF,the visualized model for the scattering characteristics of Magic black extinction coating on the aluminum alloy base of 1.0μm thickness is built.The blue box represents the measurement data and the white box represents the fitting data(Fig.4).The figures demonstrate the scattering characteristics of the coating surface BRDF values changing with different incident zenith angles and reflected zenith angles when the detection azimuth angle is 180°and the incident light wavelengths are 500 nm,550 nm,600 nm,650 nm,and 700 nm,respectively;Secondly,edge thickness detection is carried out(Fig.5).Considering the particul

关 键 词：星敏感器 遮光罩 杂散光抑制 BRDF 刃口检测 

分 类 号：O435[机械工程—光学工程]