The large spacecraft structure would generate thermal-induced vibration in orbit under specific condition, which will affect the performance of the payload. In order to predict the occurrence of thermal-induced vibration of the spacecraft structure in orbit, it is necessary to carry out tests in the ground simulated vacuum and low temperature environment. The vibration displacement of structure should be measured by laser displacement meter during the test. Due to the special environment such as vacuum, low temperature environment, it is necessary to improve the laser displacement meter. The effect of internal and external pressure difference during pumping is eliminated by design the venting holes. Ensures the temperature uniformity and operating temperature range of the laser displacement meter by thermal control design, to reduce the measurement error caused by the thermal deformation of the sensor. The adaptive design ensures that the laser displacement meter can work normally under vacuum and low temperature environment, and the measurement accuracy is better than 5μm.
Orbit target IR model can be used to design orbit target detection sensor, generating simulation data to validate the data processing algorithms, such as the target detection and tracking. In the work, a novel orbit target IR model is built. IR detection uses the difference between the target and the background to achieve the target effectually. In order to increase the application ability, the IR model consists of the orbit target and the celestial background. The geometry module and IR radiometric module make up the orbit target IR model. The professional geometry modeling software CAD is used to build the geometry model. The reflection between the subassembly is considered in the radiometric, because the thermal control coat of the satellite (such as optical solar reflector) has very high specular reflectance generally. The Midcourse Space Experiment (MSX) catalog is used to calculate the IR celestial IR background. The IR radiation provided by the MSX is used to calculate the equivalent temperature and the observation angle by the SPSO (Stochastic Particle Swarm Optimization) method. The transfer algorithm adopted in this paper is compared with the Monte-Carlo method, and the results show that the relative deviation between them is less than 10%.