| Recently, the solar propelled sail-craft has received much more attention as a new type of spacecraft, which is propelled and controlled by solar radiation pressure. No propellant is needed, no space trash is produced and no limit is from fuel. It can be used to realize missions such as deep space exploration, take sample from other planet or comet, observation solar poles etc.In this paper, the solar propelled sail-craft with lenticular boom and Kapton film was chosen to be the object, which was investigated through theoretical, experimental and numerical analysis methods to reconginze the mechanical performance of the structure and manufacture of the sail. It contains the structural mechanical analysis of the solar propelled sail-craft, mechanical behavior analysis and experiment on Kapton film folding, buckling analysis and experiment of the cantilever thin-walled lenticular CFRP boom, manufacture and test of the sail.Firstly, the finite element model of the solar propelled sail-craft was built. On the basis of linear eign-value axial compression buckling and cantilever buckling analysis of a single cantilever lenticular boom, the structural mechanical analysis of the whole sail structure was carried out to simulate the deformation of the membrane and the response of the structure under the solar radiation pressure, then the reasonable stress and the influence on the structural rigidity of solar sail were evaluated.Secondly, to unveil the mechanical behavior of folding from launch requirements, specific assumptions were proposed from the elastic engineering view. The S-Fold style was taken as the research object, the relationship between the contact force of the adjacent film and layer pitch was formulated based on linear-elastic engineering theory. The numerical simulation of the folding process was carried out in implicit static method with finite element software ABAQUS. On the basis of characteristics of S-Fold, materials tests and folding tests were performed. The results obtained in three ways were analyzed comparatively, they are in good agreements.Again, the thin-walled lenticular boom which is the diagonal extendable support of solar sail is a typical cantilever state. In order to obtain the mechanical performance of the lenticular boom, the loading tests were performed with the load applied at the cantilever end, the non-linear external buckling load and the stability of cantilever lenticular boom were obtained simultaneously. Linear buckling load was obtained by using ABAQUS. Taking the linear buckling mode as initial geometrical imperfect of the boom, the non-linear analysis was carried out under cantilever end load and the non-linear buckling load was found subsequently, then the results were compared with testing results. Based on the former analysis, the structural parameters such as thickness, number of layers and slenderness ratio were investigated and the non-linear buckling load was obtained for each case subsequently, influence and sensitivity of parameters were compared. In this paper, the numerical procedure and experimental results are valuable to the optimization design of thin-walled CFRP lenticular boom.Finally, procedure and methods of manufacturing large membrane were studied. In order to obtain large scale thermal plastic polymide film that is smooth, without spots and wrinkles, welding head pot needs to move continuously with high temperature. There are no on-stock products currently. On the basis of technique requirement, a new type of welding system was developed to manufacture the solar sail membrane and some tests were done to demonstrate the performance. |
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