受甲虫外骨骼角质层刚度分布的启发，提出了一种新型仿生刚度梯度圆环阵列防护结构，此结构具有出色的抗冲击性能，超强的刚度可编程性和形状可重构性，可拓展应用到多种尺寸比例和组装框架类型，以满足更多的实际工程抗冲击防护需求。基于数值仿真技术建立了冲击载荷作用下仿生刚度梯度圆环防护系统的有限元模型，结合实验分析和理论模型研究了应力波在仿生梯度圆环系统中的传播规律以及仿生梯度圆环系统的抗冲击力学行为和防护能力，发现凹形刚度梯度可以显著改善仿生圆环系统的防护性能。进行了完整的参数化分析来研究圆环弹性模量，半径和厚度分布对仿生刚度梯度圆环系统防护特性的影响，获得对刚度梯度进行编程的最佳解决方案。
Inspired by the stiffness distribution of the cuticle of the beetle exoskeleton, a novel type of bionic stiffness gradient ring array protective structure was proposed. This structure has excellent impact resistance, high stiffness programmability and shape reconfigurability, and can be extended to a variety of size ratios and assembly frame types to meet more practical en-gineering impact protection requirements. Based on numerical simulation technology, a finite element model of the biomi-metic stiffness gradient ring protective system under impact load is established. Combined with experimental analysis and theoretical model, the propagation law of stress wave in the bionic stiffness gradient ring system and the impact mechanical behavior and protective capability of the bionic gradient ring system are studied. The results found that the concave stiffness gradient can significantly improve the protection performance of the bionic ring system. A complete parametric analysis was carried out to study the influence of the elastic modulus, radius and thickness distribution of the ring on the protective prop-erties of the bionic stiffness gradient ring system, and the optimal solution for programming the stiffness gradient was ob-tained.
[1] 宁建国, 宋卫东, 任会兰, 马天宝. 冲击载荷作用下材料与结构的响应与防护. 固体力学学报 2010; 31:532-52.
[2] Lu GX, Yu TX. Energy absorption of structures and materials: Woodhead, 2003.
[3] Alexander RM. Principles of Animal Locomotion: Princeton University Press, 2003.
[4] Yang XF, Ma JX, Wen DS, Yang JL. Crashworthy design and energy absorption mechanisms for helicopter structures: A systematic literature review. Progress in Aerospace Sciences 2020; 114:100618.
[5] Hu DY, Luo M, Yang JL. Experimental study on crushing characteristics of brittle fibre/epoxy hybrid composite tubes. International Journal of Crashworthiness 2010; 15:401-12.
[6] Wang YF, Feng JS, Wu JH, Hu DY. Effects of fiber orientation and wall thickness on energy absorption characteristics of carbon-reinforced composite tubes under different loading conditions. Composite Structures 2016; 153:356-68.
[7] Xing BF, Hu DY, Sun YX, Yang JL, Yu TX. Effects of hinges and deployment angle on the energy absorption characteristics of a single cell in a deployable energy absorber. Thin-Walled Structures 2015; 94:107-19.
[8] Liu YD, Yu JL, Zheng ZJ, Li JR. A numerical study on the rate sensitivity of cellular metals. International Journal of Solids and Structures 2009; 46:3988-98.
[9] Li ZB, Yu JL, Guo LW. Deformation and energy absorption of aluminum foam-filled tubes subjected to oblique loading. International Journal of Mechanical Sciences 2012; 54:48-56.
[10] Dharmasena K, Queheillalt D, Wadley H, et al. Dynamic response of a multilayer prismatic structure to impulsive loads incident from water. International Journal of Impact Engineering 2009; 36:632-43.
[11] Elnasri I, Zhao H. Impact perforation of sandwich panels with aluminum foam core: A numerical and analytical study. International Journal of Impact Engineering 2016; 96:50-60.
[12] Xiang JW, Du JX. Energy absorption characteristics of bio-inspired honeycomb structure under axial impact loading. Materials Science and Engineering: A 2017; 696:283-9.
[13] Bellamkonda RV. Marine inspiration. Nature Materials 2008; 7:347.
[14] Mirkhalaf M, Zhou T, Barthelat F. Simultaneous improvements of strength and toughness in topologically interlocked ceramics. Proceedings of the National Academy of Sciences of the United States of America 2018; 115:9128-33.
[15] Yu H, Zhang Z, Liu H, Yang J, Wang L, Yang L. A new landing impact attenuation seat in manned spacecraft biologically-inspired by felids. 中国航空学报(英文版) 2015; 28(2):434-46.
[16] Yang X, Ma J, Shi Y, Sun Y, Yang J. Crashworthiness investigation of the bio-inspired bi-directionally corrugated core sandwich panel under quasi-static crushing load. Materials & Design 2017; 135:275-90.
[17] Yang X, Sun Y, Yang J, Pan Q. Out-of-plane crashworthiness analysis of bio-inspired aluminum honeycomb patterned with horseshoe mesostructure. Thin-Walled Structures 2018; 125:1-11.
[18] Yang X, Ma J, Sun Y, Yang J. Ripplecomb: a novel triangular tube reinforced corrugated honeycomb for energy absorption. Composite Structures 2018:S0263822317339442.
[19] Zhang Z, Yu H, Yang J, Wang L, Yang L. How cat lands: insights into contribution of the forelimbs and hindlimbs to attenuating impact force. Science Bulletin 2014; 59(26):3325-32.
[20] Zhang Z, Yang J, Yu H. Effect of Flexible Back on Energy Absorption during Landing in Cats: A Biomechanical Investigation. Journal of Bionic Engineering 2014; 11(4):506-16.
[21] Yu H, Yang JL, Sun YX. Energy absorption of spider orb webs during prey capture: a mechanical analysis. Journal of Bionic Engineering 2015; 12:453-63.
[22] Xing Y, Yang JL. Stiffness distribution in natural insect cuticle reveals an impact resistance strategy. Journal of Biomechanics 2020; 109:109952.
[23] Timoshenko SP. Theory of elastic stability: McGraw-Hill, 1961.
[24] Yang X, Ma J, Sun Y, Yang J. An internally nested circular-elliptical tube system for energy absorption. Thin-Walled Structures 2019; 139:281-93.
[25] Wang H, Yang J, Hua L, Sun Y, Yu TX. Internally nested circular tube system subjected to lateral impact loading. Thin-Walled Structures 2015; 91:72-81.
[26] Shim VPW, Tay BY, Stronge WJ. Dynamic Crushing of Strain-Softening Cellular Structures-A One-Dimensional Analysis. Journal of Engineering Materials and Technology 1990; 112:398-405.
[27] Gao ZY, Yu TX, Lu G. A study on type II structures. Part I: : a modified one-dimensional mass–spring model. International Journal of Impact Engineering 2005; 31(7):895-910.
[28] Gao ZY, Yu TX, Lu G. A study on type II structures. Part II: : dynamic behavior of a chain of pre-bent plates. International Journal of Impact Engineering 2005; 31(7):911-26.
[29] Johnson KL. Contact Mechanics: Cambridge University Press, 1985.
[30] Jadayil WMA, Jaber NM. Numerical prediction of optimum hollowness and material of hollow rollers under combined loading. Materials & Design 2010; 31(3):1490-6.
[31] Shim VPW, Lan R, Guo YB, Yang LM. Elastic wave propagation in cellular systems-Experiments on single rings and ring systems. International Journal of Impact Engineering 2007; 34(10):1565-84.
[32] Jafarpour M, Eshghi S, Darvizeh A, Gorb SN, Rajabi H. Functional significance of graded properties of insect cuticle supported by an evolutionary analysis. Journal of the Royal Society Interface 2020; 17:20200378.
[33] Rajabi H, Jafarpour M, Darvizeh A, Dirks JH, Gorb SN. Stiffness distribution in insect cuticle: a continuous or a discontinuous profile? Journal of the Royal Society Interface 2017; 14:20170310.
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