星敏感器光学系统的热/结构/光分析

Thermal/Structural/Optical Analysis of Optical System of Star Sensor

星敏感器是高精度的航天器姿态测量器件,其性能受太空温度环境的影响。运用有限元法和光线追迹法,建立星敏感器光学系统的热/结构/光分析模型,研究光学系统温度分布与星敏感器测量误差的关系,得到了算例光学系统在温度均匀分布条件下的温度变化以及轴向温度梯度变化、侧向温度梯度变化与星敏感器测量误差的关系曲线;给出了算例光学系统热误差小于角秒量级的温度条件:均匀温度分布条件下温度变化量≤10℃、轴向温度梯度≤0.1310℃/mm、侧向温度梯度≤0.0325℃/mm,为高精度星敏感器光学系统热控制提供科学的依据。

Star sensor is a high accurate attitude measuring instrument used in various spacecrafts,and its accuracy is restricted by ambient temperature of outer space. This paper described an effective scheme to the Thermal/Structural/Optical Analysis in optical system of star sensor. By finite element analysis （FEA） and ray tracing,the relationship of star sensor＇s measurement error and optical system＇s temperature distribution was studied. The error characteristics of a star sensor had been researched,when the temperature gradient of optical system were zero,axial and lateral respectively. Based on this scheme,optical system＇s temperature conditions can be achieved under the required measurement error caused by thermal effect of optical system. For example,if the required error is less than arcsecond level,the uniform temperature change,the axial temperature gradient and lateral temperature gradient must be less than 10℃,0.1310℃/mm and 0.0325℃/mm respectively. It provides scientific references in thermal control design of optical system of star sensor.