College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016, People's Republic of China. Institute of Bio-inspired Structure and Surface Engineering, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016, People's Republic of China.
Bioinspir Biomim. 2020 Mar 5;15(3):036006. doi: 10.1088/1748-3190/ab6ca9.
The glass sponge is a porous lightweight structure in the deep sea. It has high toughness, high strength, and high stability. In this work, a super-depth-of-field microscope was employed to observe the microstructure of the glass sponge. Based on its morphological characteristics, two novel bio-inspired lightweight structures were proposed, and the finite-element analyses (FEA) of the structures were carried out under compression, torsion, and bending loads, respectively. The structure samples were fabricated using stereolithography 3D-printing technology, and the dimension sizes of the samples were equal to those of the corresponding FEA models. Mechanical tests were performed on an electronic universal testing machine, and the results were used to demonstrate the reliability of the FEA. Additionally, lightweight numbers (LWN) were proposed to evaluate the lightweight efficiency, and a honeycomb structure was selected as the reference structure. The results indicate that the lightweight numbers of the novel bio-inspired structures are higher than those of the honeycomb structure, respectively. Finally, the proposed structures were optimized by the response surface, BP (Back Propagation) and GA-BP (Genetic Algorithm optimized Back Propagation) method. The results show that the GA-BP model after training has a high accuracy. These results can provide significant guidance for the design of tube-shaped, thin-walled structures in the engineering.
玻璃海绵是深海中的一种多孔轻质结构。它具有高韧性、高强度和高稳定性。在这项工作中，采用超景深显微镜观察玻璃海绵的微观结构。基于其形态特征，提出了两种新颖的仿生轻质结构，并分别对结构在压缩、扭转和弯曲载荷下进行了有限元分析（FEA）。采用立体光固化 3D 打印技术制造结构样品，样品的尺寸与相应的 FEA 模型相同。在电子万能试验机上进行力学测试，并将结果用于证明 FEA 的可靠性。此外，提出了轻量化系数（LWN）来评估轻量化效率，并选择蜂窝结构作为参考结构。结果表明，新颖仿生结构的轻量化系数分别高于蜂窝结构。最后，通过响应面、BP（反向传播）和 GA-BP（遗传算法优化反向传播）方法对提出的结构进行了优化。结果表明，经过训练的 GA-BP 模型具有很高的准确性。这些结果可为工程中管状、薄壁结构的设计提供重要指导。
