为提升卫星定姿精度, 采用 NOIP1SN025KA型 CMOS探测器设计了一款完整的观星相机。在辐照环境温度 24℃、测试环境温度 24℃、测试环境湿度 37% RH的环境条件下利用 60Co-γ辐射源进行了抗辐照实验。然后, 设计了焦距为 500 mm、F数为 4、视场角为 2.4.的光学系统。电子学系统以 FPGA作为核心控制器件, 控制 CMOS输出数字信号, 并通过 TLK2711将信号传回卫星数传系统。机械结构部分主要由主镜组件、次镜组件、校正镜组件、遮光罩、支腿等部分组成。采用计量筒(殷钢)支撑次镜的设计方案, 保证主次镜间隔变化在温度变化工况下满足公差要求。反射镜组件设计有径向和轴向柔性, 保证光学表面在力热环境下的面形精度。校正镜组件采用压圈切向压紧镜片的安装方式, 对镜片的应力小, 对中性好, 耐冲击和振动, 能够保持良好的结构稳定性。整机通过主镜背板与卫星连接。星载观星相机具备成像和传输星点的阈值和坐标信息两种工作模式。通过外场成像实验可知, 该相机成像质量良好、移植性强、可靠性高。视场角范围内, 可以拍摄到约 10颗星, 同时可以观测到 9等星, 可有效辅助星敏感器工作。

A complete star-viewing camera was designed using a NOIP1SN025KA CMOS detector to improve the accuracy of attitude satellites. The anti-irradiation experiment was conducted using 60Co-. radiation source under the environmental conditions of 24 ℃ irradiation temperature, 24 ℃ test temperature, and 37% RH test humidity. Subsequently, an optical system with a focal length of 500 mm, an F-number of 4, and a field of view of 2.4. are designed. The electronic system uses an FPGA as the core control device to control the CMOS output digital signal and transmits the signal back to the satellite data transmission system through TLK2711. The mechanical structure was mainly composed of a main mirror component, secondary mirror component, correction mirror component, baffle, and leg. The design scheme of the measuring cylinder (invar) supporting the secondary mirror was adopted to ensure that the interval change of the primary and secondary mirrors satisfied the tolerance requirements under the condition of temperature change. The mirror assembly was designed with radial and axial flexibility to ensure accuracy of the shape of the optical surface in the thermal environment. In the correction mirror assembly using pressure ring tangential pressing lens installation, the lens stress is small, good to neutral, impact, and vibration resistance, and can maintain good structural stability. The machine is connected to a satellite through the main mirror backplane. A star camera has two working modes: imaging and transmission of the threshold and coordinate information of the star point. Field imaging experiments showed that the camera exhibited good imaging quality, portability, and reliability. Approximately ten stars can be captured in the field of view, approximately 10 stars can be captured, and nine stars can be observed, which can effectively assist the star sensor.