The Research On Optimization Design Of The Truss For Conical Scanned Antenna Reflector

Antennas, which are responsible for the input and output of satellite’s signal, areessential equipment in the satellites. The main role of antenna reflector is to reflectelectromagnetic waves; its surface and location precision has a significant impact on theaccuracy and strength of the signal. To guarantee the shape-surface and position accuracyof the antenna reflector, the back frame structure design and truss structure optimizationdesign are conducted in this thesis. The optimization design of the truss for the antennareflector is achieved by combining3-D topology optimization with2-D topologyoptimization innovatively, which is of great theoretical significance and practical value tothe optimization design of parts for aeronautic and astronautic. The thesis’s primarycoverage is as follows:(1) The project background, significance and primary research methods are explained.Based on many literatures home and abroad, this thesis classifies current and familiarparabolic reflector antennas systematically, and introduces them briefly. The backgroundand the domestic and foreign present situation of topological optimization, mainly used inthe thesis, are illustrated.(2) The technical requirements of structure design for satellite antenna structure andantenna reflector are overviewed. The forms of common parabolic reflectors aresummarized. The fundamentals of parabolic reflectors and the process of offset parabolasconical scanning are explained. Based on given condition, the parameters of antennareflector are calculated and the models of antenna and back frames are established (threeschemes). After considering synthetically of structure type, structure materials, connectionperformance, and application scope of each connection type, the connection type betweenantenna reflector and truss is determined.(3) The basic ideas of finite element method and the functions of every module ofANYSY are described in the thesis. The models of three schemes are analyzed usingANSYS, and the third scheme is considered the best through the comparison of distortionsof static analysis, base frequencies of modal analysis, and the masses of these threemodels.(4) The structure optimization design of the truss is conducted using HyperWorks,which is based on variable density method. The material distribution of the truss isobtained by using topology optimization. And then the weight of the model established after topology optimization is lightened through size optimization, and the final model oftruss whose mass is smaller but performance meets the demands is obtained. The assemblyis gained by assembling the antenna reflector model of the third scheme and the finalmodel of truss, and then modal analysis of the assembly is conducted using ANSYS.Simulation analysis shows the models designed in the thesis meet technical requirements,which verify the rationality of the design.