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The reed structure is the key component in the foldable space deployment mechanism. In the aerospace industry, weight loss occupies a pivotal position. The use of lightweight structure can achieve significant savings in launch costs and improve load efficiency. Aiming at the lightweight requirements of the space deployment mechanism, this paper discusses the substitution effect of the honeycomb topology on the reed structure in the space deployment structure. Firstly, the column structure of the honeycomb is equivalent to an orthotropic cylindrical block-shell structure. According to the bending theory of an orthotropic cylinder, the expanded honeycomb structure equivalent to an orthotropic cylindrical block-shell structure is deduced. Then, the exact expression of the reverse bending moment was obtained, and the bending moment-curvature curve during the folding process was drawn. The bending moment-curvature characteristics during the folding process are simulated by finite element numerical simulation. By proposing the index of unit mass for analysis and comparison, the results show that compared with the common spring steel structure, the honeycomb structure has better mechanical properties per unit mass and has a certain substitution effect on the reed structure. [ABSTRACT FROM AUTHOR]

Higher energy absorption efficiency and better crashworthiness performance are always the key objectives for different energy absorbing structures applied in numerous industries including aerospace, rail equipment transportation, and automotive. In this study, a functionally graded thickness (FGT) design method is introduced in the design of a hexagon honeycomb structure to improve energy absorbing efficiency on the basis of a traditional honeycomb with uniform thickness (UT). The validation of a numerical analysis model for a UT honeycomb under axial loading is implemented by a nonlinear finite element code LS-DYNA (V971). Furthermore, the multiobjective crashworthiness optimization of an FGT honeycomb subjected to axial quasi-static compression is conducted to maximize specific energy absorption (SEA) and minimize peak crashing force (PCF). In addition, three surrogate models, including radial basis function (RBF), response surface method (RSM), and kriging (KRG), are compared in the accuracy of predicting SEA and PCF and capacity for optimization design of FGT honeycomb structure; the Nondominated Sorting Genetic Algorithm (NSGA-II) is applied to obtain the Pareto optimal solutions for the maximum thickness, minimum thickness, and thickness variation gradient exponent of a honeycomb wall. The optimal points obtained by different surrogate models subjected to an SEA value of 18.5 kJ/kg, 20 kJ/kg, 22 kJ/kg, and 24 kJ/kg are validated, and corresponding optimal parameters are compared; RBF and RSM are more suitable in crashworthiness optimization design of the FGT honeycomb structure. It is indicated that the FGT honeycomb with optimal geometrical parameters presents remarkable enhancement and energy absorbing potential compared to the traditional honeycomb structure. [ABSTRACT FROM AUTHOR]