Design And Analysis Of Spacecraft Optical Load Calibration Test System

The rapidly growing development of China’s satellite technology brings much higher requirements for space borne remote sensing instruments, especially in terms of spatial resolutions and spectral resolutions. Ground-based optical payload vacuum calibration technique is the basis for its quantitative applications. Vacuum chamber, heat sink and thermal shield in the spacecraft vacuum optical load calibration test system is the main equipment to achieve a cold space environment simulation, they are also the key to the optical calibration system. This paper focuses on these three subsystems respectively. Their structural design, mechanical properties and thermal performance are given detailed discussion and analysis.For the mechanical properties of high vacuum chamber, this paper carried out a detailed analysis and discussion. In the simulation experiments on the ground, the force in the vacuum chamber are mainly atmospheric external pressure and its own weight from gravity, vacuum chamber stress and strain characteristics in this environment is analyzed in detail. In particular, further discussions on the strength, stress analysis and displacement under external force and stability under external pressure on the vacuum chamber are given.In addition, for the structural design and performance calculation of heat sink and its components, related calculation and verification are carried out from several perspectives to meet the performance requirements, namely the thermodynamic processes, the flow resistance characteristics of liquid nitrogen, the heat sink strength, etc.Finally, cold shields and their cold source(GM refrigerator) are designed in detail. Cool shield system consists of two distinct thermal shields(low temperature and high temperature shield) to meet the different thermodynamic needs. The thermodynamic processes under steady work condition and its cooling rate in transient procedure are calculated theoretically. Furthermore, their stress and thermal stress caused by the rapid cooling are analyzed.