卫星红外遥感器辐射定标光机系统热-结构耦合变形分析

辐射定标光机系统在模拟空间环境下的热变形直接影响定标光学系统成像质量,并决定星载遥感器辐射定标试验精度.文章建立的辐射定标光机系统有限元模型,以某卫星多光谱扫描仪辐射定标试验中的实测温度变化作为温度载荷,计算和研究了该系统在真空低温环境下的热-结构耦合变形的分布情况和分布规律.结果表明:在非均匀稳态低温环境下,该系统光...

Thermal-structure coupled deformation in an optical-mechanical system for radiometric calibration of satellite IR remote sensor

The thermal deformation of a radiometric calibration optical-structure system under simulated space environments would cause a great damage to the imaging quality of the system, and reduce the precision of the calibration test eventually. In this paper, a finite element model of such a system is built. Based on the model, with the temperature values at nodes obtained in the radiometric calibration test for the satellite multi-spectral scanner, the distribution of the thermal-structure coupling deformation is calculated and analyzed. The results show that the thermal distortion of the optical bracket would cause rigid displacements of the primary mirror and the primary reflector, making them off the axis or acclivitous and the black body off the focus, and changing the focal distance of the system in a non-uniform steady-state low temperature condition. But the root-mean-square (RMS) values of deformation of the anamorphic mirrors are both less than one fortieth of the wave length, within the actual surface shape accuracy requirements of the optical system.