The Effects of Large Space Micro-Strip Antenna Thermal Distortion to Releasing and Deploying Analysis
- Paper number
IAC-06-C2.2.06
- Author
Ms. Juan-Fang Wei, Xi an Institute of Space Radio Technology, China
- Coauthor
Mr. Bo Gao, China
- Coauthor
Mr. Li Zheng-Jun, China
- Year
2006
- Abstract
Large space micro-strip array antenna is usually consisted of several single panels .The panels are stowed during launch and deployed into a plane array in obit. As the dimension of single panel is large and the difference of CTE (Coefficients of Thermal Expansion) among different material exists, each panel will have thermal distortion in orbit thermal environment. This thermal distortion will acts as thermal loads for the hold down mechanism and may affect the processing of releasing. The thermal distortion will also change the shape of deployed plane array and may change the location of components related with locking. To guarantee the successful releasing and deploying of antenna, it is very important to analysis the effects of thermal distortion. In this study the analysis and experiment have been carried out to define the thermal stress and the real array shape caused by thermal distortion in obit, and these results will be used as inputs for deploying mechanism design. A micro-strip antenna with five panels (11.4m in length after deploying) was made into FEA model both in stowed and deploying configurations. The thermal stress and distortion in different orbit temperature fields were calculated. As the conclusion of analysis, the force caused by the shrinking of metal feed line at the back of each panel in cold temperature was the main factor that made the structure panel bending. To decrease the thermal distortion of antenna panel, the connectors between the metal feed line and structure panel were designed having the function of thermal de-coupling. To verify the effeteness of de-coupling design and get the residual thermal stress, a test was executed to two full-scale panels in a vacuum van. During the test, the worst orbit temperature field was simulated and the strains on the surface of feed lines were measured as the real data of thermal loads. After applying the real thermal loads to the FEA models in both stowed and deploying configurations, the maximum thermal stress in the components of hold-down mechanism in stowed configuration and the worst distortion of antenna array during deploying were evaluated. Other large space deployable antennas may reference the indirect method used in this paper for thermal distortion assessment. Announcement by Authors The material used in this paper is new and original. The paper was not presented at a previous meeting and the financing and attendance of an author at the respective 57th IAC to present the paper is assured.
- Abstract document