载人飞船返回舱安全着陆技术是载人航天的关键技术之一。传统缓冲座椅系统能有效缓冲航天员胸背向的冲击载荷，但对水平方向冲击的缓冲能力较弱。为保障新一代载人飞船返回舱在故障着陆工况下航天员的生命安全，本文提出了一种新型并联式缓冲承载一体化系统，通过设计新型轻质变截面空心点阵作为能量吸收材料，使缓冲承载一体化系统具有多向缓冲和承载能力，省去了活塞及运动副等支撑机构，大大提升了系统重量利用效率。首先对点阵胞元及缓冲单元进行优化设计，通过准静态压缩试验及落锤冲击试验对其缓冲性能进行分析。其次，通过仿真分析方法讨论了不同斜冲击角度下空心点阵单元的变形模式，最后基于Ls-dyna有限元分析软件建立了飞船返回舱故障着陆工况下的有限元模型，分析了不同水平及竖直方向冲击的故障着陆工况下航天员过载曲线，初步验证了新一代载人飞船返回舱着陆缓冲设计方案的可行性。
The safe landing technology of manned spacecraft crew modules is one of the key technologies in manned spacecraft. Tradi-tional buffer seats can effectively absorb the impact energy in the chest-back direction of astronauts, but they have weaker cushioning capabilities against impacts in the horizontal direction. This paper proposes a novel parallel buffer-support system to ensure the life safety of astronauts in the event of a manned spacecraft's crew module's hard landing in China’s next-generation manned spacecraft. The buffer-support system has multi-directional cushioning capabilities by selecting light-weight variable-cross-section hollow lattice structures as buffers, eliminating the support mechanisms such as pistons and moving pairs, and greatly improving the weight utilization efficiency of the system. Firstly, the lattice cell and buffer unit are optimized and designed, and their performance is comparatively verified through quasi-static compression tests and drop tower impact tests. Secondly, the deformation modes of the buffer unit under different oblique impact angles are discussed through simulation analysis. Finally, a finite element model of the hard landing of the crew module is established to analyze the astronaut's acceleration curves under hard landing conditions with horizontal impacts from different directions, initially verifying the feasibility of this scheme.
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