Conventional thin-walled metallic tubular structures exhibit material inefficiencies and reduced energy absorption capacity. To overcome these limitations, hierarchical nature-inspired thin-walled multicellular tube structures have shown the promising solution in crashworthiness applications due to their greater mechanical efficacy, lightweight nature, and improved energy absorption capacity. This research article reports the experimental crashworthiness investigation and multi-attribute assessment of additively manufactured hierarchical fruit-inspired multicellular structures. Six hierarchical fruit-inspired tube structures were fabricated using the Fused Deposition Modelling (FDM) technique. The energy absorption properties of these structures were evaluated through axial static crushing experiments. The findings showed that designs of multicellular structures inspired by various fruits improve energy absorption and structural efficiency when compared to conventional metallic tubular structures. The results revealed that the lemon-inspired structure (PE-LE) exhibited the highest total energy absorption of 746 kJ and a maximum specific energy absorption capacity of 9.84 kJ/g, followed closely by the tomato-inspired structure (PE-TO). For multi-criteria decision making, the Complex Proportional Assessment (COPRAS) method was used, incorporating mass efficiency and crashworthiness performance into an integrative ranking system to determine the ideal structure. The PETG-carbon fiber based lemon-inspired structure (PE-LE) offered the best crashworthiness performance according to the obtained results. The overall outcomes offered significant new information for the development of high-performing lightweight energy-absorbing tubular structures used in automobiles and aircraft protective systems.
ObradovicJBoriaSBelingardiG. Lightweight design and crash analysis of composite frontal impact energy absorbing structures. Compos Struct2012; 94(2): 423–430. https://doi.org/10.1016/j.compstruct.2011.08.005
2.
ZhouHXuPXieS. Composite energy-absorbing structures combining thin-walled metal and honeycomb structures. Proc Inst Mech Eng F J Rail Rapid Transit2017; 231(4): 394–405. https://doi.org/10.1177/0954409716631579
3.
AbdullahNAZSaniMSMSalwaniMS, et al.A review on crashworthiness studies of crash box structure. Thin-Walled Struct2020; 153: 106795. https://doi.org/10.1016/j.tws.2020.106795
4.
LiZChenRLuF. Comparative analysis of crashworthiness of empty and foam-filled thin-walled tubes. Thin-Walled Struct2018; 124: 343–349. https://doi.org/10.1016/j.tws.2017.12.017
5.
LuJWangYZhaiX, et al.Impact behavior of a cladding sandwich panel with aluminum foam-filled tubular cores. Thin-Walled Struct2021; 169: 108459. https://doi.org/10.1016/j.tws.2021.108459
XingJZhaoJNiuQ, et al.Crashworthiness design and optimization of bamboo-inspired tube with gradient multi-cells. Thin-Walled Struct2023; 191: 111034. https://doi.org/10.1016/j.tws.2023.111034
9.
YuanSWeiYGongJ, et al.Compressive behavior of improved star-shaped honeycomb multi-cell structures: experiments and simulations. Mech Adv Mater Struct2025; 33: 1–15. https://doi.org/10.1080/15376494.2025.2457126
10.
MaYHuangHDengX. Research on the in-plane energy absorption characteristics of the novel rotating self-similar star-shaped honeycomb structure. Eng Fail Anal2026; 189: 110696. https://doi.org/10.1016/j.engfailanal.2026.110696
11.
DengXQinSHuangJ. Crashworthiness analysis of gradient hierarchical multicellular columns evolved from spatial folding. Mater Des2022; 215: 110435. https://doi.org/10.1016/j.matdes.2022.110435
HuangCDengX. Investigation of energy absorption in double square bio-inspired hierarchical multicellular structures under axial impact. J Mater Eng Perform2025: 1–23. https://doi.org/10.1007/s11665-025-12949-x
14.
IngroleAHaoALiangR. Design and modeling of auxetic and hybrid honeycomb structures for in-plane property enhancement. Mater Des2017; 117: 72–83. https://doi.org/10.1016/j.matdes.2016.12.067
DengXWangGCaiZ. Crashworthiness of multicellular tubes with tree-like fractal hierarchical structure under axial impact. Mech Adv Mater Struct2024; 31(28): 10081–10097. https://doi.org/10.1080/15376494.2023.2284430
17.
SanHNLeeTUTranDT, et al.Efficient energy absorption of bio-inspired bi-directional gradient hierarchical multi-cell structure. Int J Mech Sci2024; 278: 109492.
ZhangYFuHXuS, et al.A hierarchical computational model for stretchable interconnects with fractal-inspired designs. J Mech Phys Solid2014; 72: 115–130. https://doi.org/10.1016/j.jmps.2014.07.011
20.
XieZDengX. Design of hierarchical multi-cell double circular tubes thin-walled structures for energy absorption. Mech Adv Mater Struct. 2025; 32(11): 2493–2510.
ChenDGaoKYangJ, et al.Functionally graded porous structures: analyses, performances, and applications. Thin-Walled Struct2023; 191: 111046. https://doi.org/10.1016/j.tws.2023.111046
24.
NikkhahHBaroutajiAOlabiAG. Crashworthiness design and optimisation of windowed tubes under axial impact loading. Thin-Walled Struct2019; 142: 132–148. https://doi.org/10.1016/j.tws.2019.04.052
25.
KulkarniSMPriyalVMaliKD, et al.Selection of material for crash-box using multi-attribute group decision-making. Int J Crashworthiness2023; 28(5): 616–628. https://doi.org/10.1080/13588265.2022.2111489
26.
SchmirlerMAbdullahJSinghMP, et al. Harnessing fractal theory for enhanced design and manufacturing in 3D printing: a review. Fractals. 2025; 33: 2530003-1– 2530003-9.
27.
ShanWLiuJZhouJ. Integrated method for intelligent structural design of steel frames based on optimization and machine learning algorithm. Eng Struct2023; 284: 115980. https://doi.org/10.1016/j.engstruct.2023.115980
28.
RamuPThananjayanPAcarE, et al.A survey of machine learning techniques in structural and multidisciplinary optimization. Struct Multidiscip Optim2022; 65(9): 266. https://doi.org/10.1007/s00158-022-03369-9
29.
SeidelRThielenMSchmittC, et al.Fruit walls and nut shells as an inspiration for the design of bio-inspired impact resistant hierarchically structured materials. Des Nat V2010; 138: 421–430.
30.
IsaacCWSokołowskiADuddeckF, et al.Mechanical characterisation and crashworthiness performance of additively manufactured polymer-based honeycomb structures under in-plane quasi-static loading. Virtual Phys Prototyp2023; 18(1): e2273296. https://doi.org/10.1080/17452759.2023.2273296
31.
SivakumarNKPalaniyappanSVishalK, et al.Crushing behavior optimization of octagonal lattice-structured thin-walled 3D printed carbon fiber reinforced PETG composite tubes under axial loading. Polym Compos2024; 45(2): 1228–1249. https://doi.org/10.1002/pc.27848
32.
KumarAPSundaramMS. Axial crushing characteristics of hybrid kenaf/glass fabric wrapped aluminium capped tubes under static loading. Int J Mech Prod Eng Res Dev2018; 8(6): 201–206.
33.
MaQRejabMRMAzeemM, et al.Axial and radial crushing behaviour of thin-walled carbon fiber-reinforced polymer tubes fabricated by real-time winding angle measurement system. Forces Mech2023; 10: 100170. https://doi.org/10.1016/j.finmec.2023.100170
34.
Praveen KumarANagarjunJMaQ. Potentiality of MWCNT fillers on lateral crashworthiness behaviour of polymer composite cylindrical tubes under quasi-static loading. J Ind Text2022; 51(4 Suppl): 7014S–7033S. https://doi.org/10.1177/1528083721997927
35.
MaQRejabMRMSongY, et al.Effect of infill pattern of PLA 3D-printed integral sandwich panels under ballistic impact loading. Mater Today Commun2024; 38: 107626. https://doi.org/10.1016/j.mtcomm.2023.107626
36.
KumarPMaQ. Evaluation of energy absorption enhancement of additively manufactured polymer composite lattice structures. Funct Compos Struct2023; 5(1): 015005. https://doi.org/10.1088/2631-6331/acc0d0
37.
Esmaeili-MarzdashtiSPirmohammadSEsmaeili-MarzdashtiS. Crashworthiness analysis of S-shaped structures under axial impact loading. Lat Am J Solid Struct2017; 14: 743–764. https://doi.org/10.1590/1679-78253430
38.
AwdAMMAbbasMAAlmuflihAS, et al.Influence of infill pattern structures on crashworthiness performance of 3D printed tubes under lateral loading. Fibers Polym2024; 25(11): 4437–4451.
39.
AwdAMMAbd El-HalimMFAlmuflihAS, et al. Innovative high-performance hybrid composite materials for crashworthiness applications. Polym Compos. 2025; 46(13): 11832–11853.
40.
LiangRLiuXHuY, et al.Methodology to investigate and optimise crashworthiness response of foam-filled twelve right-angle thin-walled structures under axial impact. Compos Struct2023; 310: 116736. https://doi.org/10.1016/j.compstruct.2023.116736
41.
LiZMaWXuP, et al.Crashworthiness of multi-cell circumferentially corrugated square tubes with cosine and triangular configurations. Int J Mech Sci2020; 165: 105205. https://doi.org/10.1016/j.ijmecsci.2019.105205
42.
TranTHouSHanX, et al.Crushing analysis and numerical optimization of angle element structures under axial impact loading. Compos Struct2015; 119: 422–435. https://doi.org/10.1016/j.compstruct.2014.09.019
43.
LiuQLiuQZhouY, et al.Identifying vibration characteristics of hemispherical resonators with mass defects. Int J Mech Sci2025; 306: 110856. https://doi.org/10.1016/j.ijmecsci.2025.110856
AshokDBahubalendruniMR. Design and characterization of 2.5D nature-inspired infill structures under out-of-plane quasi-static loading. Adv Mater Sci Eng2023; 2023: 8918937.
46.
SiddiqueSHHazellPJPereiraGG, et al.Mechanical behaviour of biomimetic cornstalk-inspired lightweight structures. Biomimetics2023; 8(1): 92. https://doi.org/10.3390/biomimetics8010092
BrownCE. Coefficient of variation. In: Applied multivariate statistics in geohydrology and related sciences. Berlin (Germany): Springer, 1998, pp. 155–157.
50.
SunMLiMOuyangQ, et al.A novel variable stiffness bio-inspired metamaterial with high cushioning property. Thin-Walled Struct2026; 220: 114358. https://doi.org/10.1016/j.tws.2025.114358
51.
MauludDAbdulazeezAM. A review on linear regression comprehensive in machine learning. J Appl Sci Technol Trends2020; 1(2): 140–147. https://doi.org/10.38094/jastt1457
52.
AlmaÖG. Comparison of robust regression methods in linear regression. Int J Contemp Math Sci2011; 6(9): 409–421.
53.
LiMQiSHuangG, et al.Blast protection and dynamic response of airbags and foam/airbag composite structures: mechanisms and structural parameter effects. Thin-Walled Struct2026; 218: 114089. https://doi.org/10.1016/j.tws.2025.114089
KGA. Effect of number of stiffeners on lateral deformation behavior of additively manufactured thin-walled cylindrical tubes. Mech Adv Mater Struct2024; 31(15): 1–12.
58.
KumarAPSankarLPManeiahD, et al.Crashworthiness characteristics of multi-cell tubular structures subjected to axial impact. Int J Recent Technol Eng2019; 8(4): 3911–3914.
KumarAPShunmugasundaramMSivasankarS, et al.Evaluation of axial crashworthiness performance of composite wrapped metallic circular tubular structures. Mater Today Proc2020; 27: 1268–1272.
61.
Praveen KumarAVetrivelSM. Influence of curvy stiffeners on axial crushing response of 3D-printed polymer composite cylindrical tubular structures. Proc Inst Mech Eng L J Mater Des Appl2023; 237(12): 2473–2485.
62.
ZhuPPanFChenW, et al.Support vector regression in structural optimization: application to vehicle crashworthiness design. Math Comput Simulat2012; 86: 21–31. https://doi.org/10.1016/j.matcom.2011.11.008
63.
WangZLiJLiuX, et al.Diameter-adjustable mandrel for thin-wall tube bending and its domain knowledge-integrated optimization design framework. Eng Appl Artif Intell2025; 139: 109634. https://doi.org/10.1016/j.engappai.2024.109634
64.
WangWZhangCZhouY, et al.Attenuation mechanisms of ultralow-frequency seismic metamaterials via complex band structure analysis. Soil Dynam Earthq Eng2026; 203: 110140. https://doi.org/10.1016/j.soildyn.2026.110140
65.
WangLWangZZhangS, et al.Multi-unit global-local registration for 3D bent tube based on implicit structural feature compatibility. Adv Eng Inform2025; 65: 103120. https://doi.org/10.1016/j.aei.2025.103120
