科學與應用的研究透過複雜度、多樣性、優化設計以及改善機械性能，使其受到各行各業的青睞。螺旋型彈簧雖然受到許多限制，如製造技術、自由度的設計與統一規格，使其僅具有簡單的設計，但彈簧仍是解決工業問題不可或缺的角色。綜觀所有的彈簧皆是利用傳統製造程序進行生產，透過傳統製程無法製造具改善機械性能的幾何與尺寸多樣性設計，其中也包含了機械性能較為出色的波形彈簧。
工業4.0與智能工業掀起了製造產業的革命，其加速了永續發展與結構輕量化的設計。根據工業4.0的特性將能源加工材料應用於製程使其創造綠色與零碳排放已成為工業界首要目標。波形彈簧憑藉著獨特的設計，相比於其他類型的彈簧具有更好的機械性能。根據文獻回顧鮮有積層製造研究與技術應用於波形彈簧。因此本研究將利用積層製造的特性進行多方面的探討，例如:複合設計、幾何尺寸、型態、線圈的截面變化等。
本研究旨在使用積層製造技術設計接觸式、非接觸式波形彈簧、幾何與尺寸變化的複合設計，並針對不同的機械性能進行分析，並使用MultiJet Fusion技術(HP, 4200)進行3D列印，相較於其他積層製造技術是一種複合且快速的工藝。本研究基於實驗和模擬以驗證波形彈簧的機械性能，研究的最後選擇最佳設計進行進一步研究和優化，通過改變每個線圈的形態或厚度基於圓線與矩形扁平條帶線圈的互相結合，從而產生混合和功能梯度波形彈簧(FGWS)，這些參數變化讓接觸式波形彈簧具有不同的機械性能。
功能梯度波形彈簧設計應用於多功能中底的研究，整個中底由晶格結構組成，而在關鍵區域（足底壓力最高的區域如：腳跟、前腳掌和腳趾）使用波形彈簧。將設計的中底與市售的功能性金屬彈簧中底進行比較，發現使用積層製造的波形彈簧在能量吸收方面較好。此外波形彈簧設計需要專業的設計和建模知識，因為沒有專門設計波形彈簧的軟體，本研究亦開發了波形彈簧的數學設計模型，即 WSdesign，此模型的使用者透過直覺的圖形用戶界面定義每個設計參數，並生成可以直接列印或進一步分析的波形彈簧。
此研究證明，積層製造的優勢可以很好的設計與製造複雜結構。根據此研究結果，具有可變尺寸和幾何形狀的接觸式波形彈簧能顯著改善的機械性能，另外帶狀形態已被證明是機械性能的關鍵因素，即扁平帶狀具有更好的承載能力，而圓線則增加了波形彈簧的能量吸收，相同地，每個線圈的波數、重疊和波高與承載能力、剛性和能量吸收成正比。相較於傳統的非接觸式金屬波形彈簧，聚合物接觸式波形彈簧表現出良好的疲勞和緩衝性能，這些特性提供了醫療和鞋類等行業能有更好且安全的選擇，因市售的彈簧多為金屬彈簧，這些金屬彈簧對人體具有不同形式的潛在危害。

Scientific and application-based research has broadened its horizons by the addition of complex, intricate but optimized designs with improved mechanical properties which are beneficial to every industry. Springs such as helical type, although having simple designs due to various manufacturing constraints, limited design freedom, and customized setups, is an integral part of the solution to many industrial problems and fulfilling the industrial requirements. All springs including wave springs that are considered to have better mechanical properties than other types are manufactured by traditional manufacturing processes using customized machines. These fabrication units cannot manufacture complex designs having geometric and dimensional variations that can have improved mechanical properties.
Industry 4.0 or smart industry is a revolution of manufacturing that addressed/improved many aspects including sustainability and light-weighting of the design/structure. It also leads to green and zero-carbon manufacturing i.e., the application of energy to process the material without emission of carbon which has become the prime objective of almost all industrial hubs. Wave springs have a unique and optimized design that has better mechanical properties than other types of springs. Based on the literature review, it was observed that there is hardly any research or attempts to manufacture wave springs using additive manufacturing. So, many aspects need to be addressed and explored such as complexity of design, geometric/dimensional variations, morphology, cross-sectional change of coils, etc. To fulfill these research gaps, it was imperative to design and manufacture wave springs using the design freedom of additive manufacturing.
This study aims to design and additive manufacture (AM) contact and non-contact wave springs along with complex designs having geometric as well as dimensional variations and analyzed for different mechanical properties. All designs were printed using MultiJet fusion technology (HP, 4200) which is a hybrid and fast process as compared to other AM techniques. Both experimental and simulation-based studies were carried out to investigate and validate the mechanical properties of wave springs. Finally, the best designs were chosen for further studies and optimization. Several wave springs were designed by varying the morphology or thickness of each coil, also by the combination of round wire-based coils with rectangular flat strip-based coils resulting in hybrid and functionally gradient wave springs (FGWS). All these parametric changes resulted in contact wave springs with improved mechanical properties.
FGWS were used for the application/case study of a multifunctional midsole that was designed to incorporate wave springs at the critical area i.e., highest plantar pressure areas (heel, forefoot, and toe) while the entire midsole was comprised of the lattice structure. The designed midsole was compared with commercially available spring-based functional midsoles in which metal springs were used for energy absorption. AM wave springs were found to be better in energy absorption and return than metal wave springs. Additionally, it was found that wave spring designing needs in-depth design knowledge and CAD modeling expertise as there was no direct algorithm/software to design wave springs. Hence, a study was conducted to mathematically design a process of wave spring in which an algorithm was developed i.e., WSDesign. It allows the user to define each parameter of the required wave spring design through a user-friendly GUI (graphical user interface), and generates the spring which can be printed directly or considered for further analysis.
This research proved that additive manufacturing with its unlimited design freedom undoubtedly played an important part to design and manufacture complex structures which are almost impossible using traditional manufacturing processes with improved mechanical properties. It was concluded that additively manufactured contact wave springs with variable dimensions and geometric shapes have significantly improved mechanical properties. The strip morphology proved to be a key factor for the mechanical performance i.e., the flat strip exhibits better load-bearing capacity while round wire increases the energy absorption of the wave spring. Similarly, the number of waves per coil, overlapping, and wave height ha a direct proportion to load-bearing capacity, stiffness, and energy absorption. These polymeric contact wave springs also showed good fatigue and cushioning properties as compared to traditional non-contact metal wave springs. These improved properties made this a better and safe choice for different industries including medical and footwear as commercially available spring-based applications use metal springs which always have a potential hazard in different forms for the human body.

REFERENCES
[1] J.K.N.Joseph Edward Shigley, Richard G.Budynas, Mechanical Engineering Design, 10th ed., McGraw Hill, 2015.
[2] Peter R.N. Childs, Mechanical Design Engineering Handbook, Butterworth-Heinemann, 2014. https://doi.org/10.1016/C2011-0-04529-5.
[3] Wave Springs- Advantages. https://www.rotorclip.com/wave_spring_advantage1.php.
[4] Smalley Wave Springs Smalley. https://www.smalley.com/wave-springs.
[5] Smalley, Wave Spring vs. Coil Spring | Smalley. https://www.smalley.com/blog/wave-spring-vs-coil-spring.
[6] Custom Wave Spring Manufacturer Teamco,. https://www.teamco.com.tw/en/product/wave-spring.html.
[7] Retaining Rings, Spiral Rings, Constant Section Rings, Wave Springs. https://www.rotorclip.com/.
[8] US20050126039A1 - Spring cushioned shoe - Google Patents. https://patents.google.com/patent/US20050126039.
[9] US20090292363 - INTERVERTEBRAL PROSTHESIS WEBPAT. https://webpat.tw/webpat/patent-detail.cshtml#/patent-info/?database=US&displayType=published&esId=us_20090292363_12470690&rowIndex=40&storageId=resultStorage_invention plant reissue sir defensive TVPP_1597726597104.
[10] US9039766B1 - Wave spring for a spinal implant - Google Patents. https://patents.google.com/patent/US9039766B1/en?q=wave+springs&oq=wave+springs.
[11] E.Dragoni, A contribution to wave spring design, J. Strain Anal. Eng. Des. 23 (1988) 145–153. https://doi.org/10.1243/03093247V233145.
[12] H.R.Erfanian-Naziftoosi, S.S.Shams, R.Elhajjar, Composite wave springs: Theory and design, Mater. Des. 95 (2016) 48–53. https://doi.org/10.1016/j.matdes.2016.01.073.
[13] N.T.Panagiotopoulos, K.Georgarakis, A.M.Jorge, M.Aljerf, W.J.Botta, A.L.Greer, A.R.Yavari, Advanced ultra-light multifunctional metallic-glass wave springs, Mater. Des. 192 (2020) 108770. https://doi.org/10.1016/j.matdes.2020.108770.
[14] S.Chandrasekaran, R.Lu, R.Landingham, J.T.Cahill, L.Thornley, W.DuFrane, M.A.Worsley, J.D.Kuntz, Additive manufacturing of graded B4C-Al cermets with complex shapes, Mater. Des. 188 (2020) 108516. https://doi.org/10.1016/j.matdes.2020.108516.
[15] US9861207B2 - Wave springs and cushioning articles containing the same - Google Patents.,https://patents.google.com/patent/US9861207B2/en?q=Wave+springs+and+cushioning+articles&oq=Wave+springs+and+cushioning+articles+.
[16] US20090292363A1 - Intervertebral prosthesis - Google Patents. https://patents.google.com/patent/US20090292363.
[17] US6758465B1 - Wave spring with single shim end - Google Patents. https://patents.google.com/patent/US6758465B1/en?q=Wave+spring+single+shim+end%2C&oq=Wave+spring+with+single+shim+end%2C.
[18] US7441347B2 - Shock-resistant shoe - Google Patents. https://patents.google.com/patent/US7441347B2/en?q=Shock+resistance+shoe%2C&oq=Shock+resistance+shoe%2C.
[19] US20080209762A1 - Spring cushioned shoe - Google Patents. https://patents.google.com/patent/US20080209762A1/en?q=Spring+cushioned+shoe&oq=Spring+cushioned+shoe.
[20] US20020174661A1 - Wave spring-loaded split seal system - Google Patents. https://patents.google.com/patent/US20020174661A1/en?q=Wave+spring-loaded+split+seal+system%2C+russell+sylvia&oq=Wave+spring-loaded+with+split+seal+system%2C+russell+sylvia.
[21] US8167215B2 - Thermostatic mixing valves utilizing wave springs - Google Patents https://patents.google.com/patent/US8167215B2/en?q=Thermostatic+mixing+valves+utilizing+wave+spring%2C&oq=Thermostatic+mixing+valves+utilizing+wave+spring%2C.
[22] US8875683B2 - Two-phase spring - Google Patents. https://patents.google.com/patent/US8875683B2/en?q=Two-phase+spring%2Cjason&inventor=d+holt&oq=Two-phase+spring%2Cjason+d+holt.
[23] Wave spring Technology – SPIRA INC https://spira.com/pages/wavespring-technology.
[24] Wave Spring Application Examples | Smalley. https://www.smalley.com/wave-springs/application-examples (accessed May 14, 2022).
[25] Designation: F2792 − 12a. https://doi.org/10.1520/F2792-12A.
[26] Photopolymerization - VAT, SLA, DLP, CDLP Make. https://make.3dexperience.3ds.com/processes/photopolymerization.
[27] ADDITIVE MANUFACTURING/3D PRINTING: THINK BEYOND THE POSSIBILITIES. https://additivemanufacturingindia.blogspot.com/2018/04/additive-manufacturing-overview.html.
[28] Powder Bed Fusion Additive Manufacturing Research Group Loughborough University.https://www.lboro.ac.uk/research/amrg/about/the7categoriesofadditivemanufacturing/powderbedfusion/.
[29] B.S.I. Gibson, D.W. Rosen, Additive Manufacturing Technologies, Springer, 2010.
[30] B.Yelamanchi, B.Mummareddy, C.C.Santiago, B.Ojoawo, K.Metsger, B.Helfferich, J.Zapka, F.Sillani, E.MacDonald, P.Cortes, Mechanical and fatigue performance of pressurized vessels fabricated with Multi Jet Fusion for automotive applications, Addit. Manuf. 44 (2021) 102048. https://doi.org/10.1016/J.ADDMA.2021.102048.
[31] B.Guo, Z.Xu, X.Luo, J.Bai, A detailed evaluation of surface, thermal, and flammable properties of polyamide 12/glass beads composites fabricated by multi jet fusion, Virtual Phys. Prototyp. 16 (2021) S39–S52. https://doi.org/10.1080/17452759.2021.1899463/SUPPL_FILE/NVPP_A_1899463_SM7159.DOC.
[32] P.V.Osswald, P.Obst, G.A.Mazzei Capote, M.Friedrich, D.Rietzel, G.Witt, Failure criterion for PA 12 multi-jet fusion additive manufactured parts, Addit. Manuf. 37 (2021) 101668. https://doi.org/10.1016/J.ADDMA.2020.101668.
[33] F.Sillani, R.G.Kleijnen, M.Vetterli, M.Schmid, K.Wegener, Selective laser sintering and multi jet fusion: Process-induced modification of the raw materials and analyses of parts performance, Addit. Manuf. 27 (2019) 32–41. https://doi.org/10.1016/J.ADDMA.2019.02.004.
[34] F.N.Habib, P.Iovenitti, S.H.Masood, M.Nikzad, Fabrication of polymeric lattice structures for optimum energy absorption using Multi Jet Fusion technology, Mater. Des. 155 (2018) 86–98. https://doi.org/10.1016/J.MATDES.2018.05.059.
[35] H.J.O’Connor, A.N.Dickson, D.P.Dowling, Evaluation of the mechanical performance of polymer parts fabricated using a production scale multi jet fusion printing process, Addit. Manuf. 22 (2018) 381–387. https://doi.org/10.1016/J.ADDMA.2018.05.035.
[36] M.Seabra, J.Azevedo, A.Araújo, L.Reis, E.Pinto, N.Alves, R.Santos, J.Pedro Mortágua, Selective laser melting (SLM) and topology optimization for lighter aerospace componentes, in: Procedia Struct. Integr., Elsevier B.V., 2016: pp. 289–296. https://doi.org/10.1016/j.prostr.2016.02.039.
[37] M.Brandt, S.Sun, M.Leary, S.Feih, J.Elambasseril, Q.Liu, High-value SLM aerospace components: From design to manufacture, Adv. Mater. Res. 633 (2013) 135–147. https://doi.org/10.4028/www.scientific.net/AMR.633.135.
[38] L.Zhang, B.Song, J.J.Fu, S.S.Wei, L.Yang, C.Z.Yan, H.Li, L.Gao, Y.S.Shi, Topology-optimized lattice structures with simultaneously high stiffness and light weight fabricated by selective laser melting: Design, manufacturing and characterization, J. Manuf. Process. 56 (2020) 1166–1177. https://doi.org/10.1016/j.jmapro.2020.06.005.
[39] J.Piekło, M.Małysza, R.Dańko, Modelling of the material destruction of vertically arranged honeycomb cellular structure, Arch. Civ. Mech. Eng. 18 (2018) 1300–1308. https://doi.org/10.1016/j.acme.2018.03.007.
[40] L.Krog, A.Tucker, M.Kemp, R.Boyd, Topology Optimisation of Aircraft Wing Box Ribs, in: 10th AIAA/ISSMO Multidiscip. Anal. Optim. Conf., American Institute of Aeronautics and Astronautics, Reston, Virigina, 2004. https://doi.org/10.2514/6.2004-4481.
[41] A.M.Mirzendehdel, K.Suresh, Support structure constrained topology optimization for additive manufacturing, CAD Comput. Aided Des. 81 (2016) 1–13. https://doi.org/10.1016/j.cad.2016.08.006.
[42] K.Suresh, Efficient microstructural design for additive manufacturing, in: Proc. ASME Des. Eng. Tech. Conf., 2014. https://doi.org/10.1115/DETC201434383.
[43] M.Tomlin, J.Meyer, Topology Optimization of an Additive Layer Manufactured (ALM) Aerospace Part, 7th Altair CAE Technol. Conf. 2011. (2011) 1–9.
[44] F.Xu, X.Zhang, H.Zhang, A review on functionally graded structures and materials for energy absorption, Eng. Struct. 171 (2018) 309–325. https://doi.org/10.1016/j.engstruct.2018.05.094.
[45] N.S.Ha, G.Lu, A review of recent research on bio-inspired structures and materials for energy absorption applications, Compos. Part B Eng. 181 (2020) 107496. https://doi.org/10.1016/j.compositesb.2019.107496.
[46] H.Nikkhah, A.Baroutaji, Z.Kazancı, A.Arjunan, Evaluation of crushing and energy absorption characteristics of bio-inspired nested structures, Thin-Walled Struct. 148 (2020) 106615. https://doi.org/10.1016/j.tws.2020.106615.
[47] F.Tarlochan, S.Ramesh, Composite sandwich structures with nested inserts for energy absorption application, Compos. Struct. 94 (2012) 904–916. https://doi.org/10.1016/j.compstruct.2011.10.010.
[48] F.Tarlochan, S.Ramesh, S.Harpreet, Advanced composite sandwich structure design for energy absorption applications: Blast protection and crashworthiness, Compos. Part B Eng. 43 (2012) 2198–2208. https://doi.org/10.1016/j.compositesb.2012.02.025.
[49] L.Zhang, S.Feih, S.Daynes, S.Chang, M.Y.Wang, J.Wei, W.F.Lu, Energy absorption characteristics of metallic triply periodic minimal surface sheet structures under compressive loading, Addit. Manuf. 23 (2018) 505–515. https://doi.org/10.1016/j.addma.2018.08.007.
[50] G.Imbalzano, S.Linforth, T.D.Ngo, P.V.S.Lee, P.Tran, Blast resistance of auxetic and honeycomb sandwich panels: Comparisons and parametric designs, Compos. Struct. 183 (2018) 242–261. https://doi.org/10.1016/j.compstruct.2017.03.018.
[51] L.L.Hu, M.Z.Zhou, H.Deng, Dynamic crushing response of auxetic honeycombs under large deformation: Theoretical analysis and numerical simulation, Thin-Walled Struct. 131 (2018) 373–384. https://doi.org/10.1016/j.tws.2018.04.020.
[52] J.Huang, Q.Zhang, F.Scarpa, Y.Liu, J.Leng, In-plane elasticity of a novel auxetic honeycomb design, Compos. Part B Eng. 110 (2017) 72–82. https://doi.org/10.1016/j.compositesb.2016.11.011.
[53] L.DiLandro, G.Sala, D.Olivieri, Deformation mechanisms and energy absorption of polystyrene foams for protective helmets, Polym. Test. 21 (2002) 217–228. https://doi.org/10.1016/S0142-9418(01)00073-3.
[54] X.Zhang, G.Cheng, A comparative study of energy absorption characteristics of foam-filled and multi-cell square columns, Int. J. Impact Eng. 34 (2007) 1739–1752. https://doi.org/10.1016/j.ijimpeng.2006.10.007.
[55] T.A.Turner, N.A.Warrior, F.Robitaille, C.D.Rudd, The influence of processing variables on the energy absorption of composite tubes, Compos. Part A Appl. Sci. Manuf. 36 (2005) 1291–1299. https://doi.org/10.1016/j.compositesa.2005.01.012.
[56] O.Al-Ketan, D.W.Lee, R.Rowshan, R.K.Abu Al-Rub, Functionally graded and multi-morphology sheet TPMS lattices: Design, manufacturing, and mechanical properties, J. Mech. Behav. Biomed. Mater. 102 (2020) 103520. https://doi.org/10.1016/j.jmbbm.2019.103520.
[57] O.Al-Ketan, R.K.Abu Al-Rub, Multifunctional Mechanical Metamaterials Based on Triply Periodic Minimal Surface Lattices, Adv. Eng. Mater. 21 (2019) 1900524. https://doi.org/10.1002/adem.201900524.
[58] A.Nazir, A.BinArshad, J.-Y.Jeng, Buckling and Post-Buckling Behavior of Uniform and Variable-Density Lattice Columns Fabricated Using Additive Manufacturing, Materials (Basel). 12 (2019) 3539. https://doi.org/10.3390/ma12213539.
[59] A.Nazir, J.Y.Jeng, Buckling behavior of additively manufactured cellular columns: Experimental and simulation validation, Mater. Des. 186 (2020) 108349. https://doi.org/10.1016/j.matdes.2019.108349.
[60] Types of Springs - A Thomas Buying Guide. https://www.thomasnet.com/articles/machinery-tools-supplies/types-of-springs/.
[61] T.H.E.Effect, O.F.Diversity, O.F.The, B.Of, I.Decision, F.Decision, D.Policy, T.O.Company, Impact Factor : International Scientific Journal Theoretical & Applied Science THE EFFECT OF DIVERSITY OF THE NATIONALITY , BOARD OF DIRECTOR , INVESTMENT DECISION , FINANCING DECISION , AND Impact Factor :, (2000). https://doi.org/10.15863/TAS.
[62] A.Nazir, M.Ali, C.-H.Hsieh, J.-Y.Jeng, Investigation of stiffness and energy absorption of variable dimension helical springs fabricated using multijet fusion technology, Int. J. Adv. Manuf. Technol. 110 (2020) 2591–2602. https://doi.org/10.1007/s00170-020-06061-8.
[63] J.Ke, Z. yuWu, Y. shengLiu, Z.Xiang, X. dongHu, Design method, performance investigation and manufacturing process of composite helical springs: A review, Compos. Struct. 252 (2020) 112747. https://doi.org/10.1016/j.compstruct.2020.112747.
[64] M.Taktak, K.Omheni, A.Aloui, F.Dammak, M.Haddar, Dynamic optimization design of a cylindrical helical spring, Appl. Acoust. 77 (2014) 178–183. https://doi.org/10.1016/j.apacoust.2013.08.001.
[65] J.Ke, Z. yuWu, X. yingChen, Z. pingYing, A review on material selection, design method and performance investigation of composite leaf springs, Compos. Struct. 226 (2019) 111277. https://doi.org/10.1016/j.compstruct.2019.111277.
[66] J.H.D.Foard, D.Rollason, A.N.Thite, C.Bell, Polymer composite Belleville springs for an automotive application, Compos. Struct. 221 (2019) 110891. https://doi.org/10.1016/j.compstruct.2019.04.063.
[67] SPIRA INC. https://spira.com/.
[68] gikedi2019 | Welcome. https://www.gikedi.com/.
[69] M.Ali, A.Nazir, J.-Y.Jeng, Mechanical performance of additive manufactured shoe midsole designed using variable-dimension helical springs, Int. J. Adv. Manuf. Technol. 2020 11111. 111 (2020) 3273–3292. https://doi.org/10.1007/S00170-020-06227-4.
[70] Compression Springs - Precision Coil Spring,. https://www.pcspring.com/products/compression-springs/.
[71] A.Nazir, M.Ali, C.-H.Hsieh, J.-Y.Jeng, Investigation of stiffness and energy absorption of variable dimension helical springs fabricated using multijet fusion technology, Int. J. Adv. Manuf. Technol. 2020 1109. 110 (2020) 2591–2602. https://doi.org/10.1007/S00170-020-06061-8.
[72] M.Ali, A.Nazir, J.-Y.Jeng, Mechanical performance of additive manufactured shoe midsole designed using variable-dimension helical springs, Int. J. Adv. Manuf. Technol. 2020 11111. 111 (2020) 3273–3292. https://doi.org/10.1007/S00170-020-06227-4.
[73] A.BinArshad, A.Nazir, J.-Y.Jeng, Design and performance evaluation of multi-helical springs fabricated by Multi Jet Fusion additive manufacturing technology, Int. J. Adv. Manuf. Technol. 2021. (2021) 1–12. https://doi.org/10.1007/S00170-021-07756-2.
[74] SOLIDWORKS, (n.d.). https://www.solidworks.com/.
[75] Modeling a Wave Spring in SOLIDWORKS > ENGINEERING.com. https://www.engineering.com/DesignSoftware/DesignSoftwareArticles/ArticleID/10242/Modeling-a-Wave-Spring-in-SOLIDWORKS.aspx.
[76] M.R. ulHaq, A.Nazir, J.Y.Jeng, Design for additive manufacturing of variable dimension wave springs analyzed using experimental and finite element methods, Addit. Manuf. 44 (2021) 102032. https://doi.org/10.1016/J.ADDMA.2021.102032.
[77] S.R.Geiringer, The biomechanics of running, J. Back Musculoskelet. Rehabil. 5 (1995) 273–279. https://doi.org/10.3233/BMR-1995-5404.
[78] F-Scan System Tekscanhttps://www.tekscan.com/products-solutions/systems/f-scan-system.
[79] F-Scan System | In-Shoe Pressure Measurement Foot Function Gait Analysis System | Tekscan, (n.d.). https://www.tekscan.com/products-solutions/systems/f-scan-system.
[80] Walk Briskly for Your Health. About 100 Steps a Minute. - The New York Times. https://www.nytimes.com/2018/06/27/well/walk-health-exercise-steps.html.
[81] Next-Generation Engineering Design Software nTopology. https://ntopology.com/.
[82] D.Li, W.Liao, N.Dai, G.Dong, Y.Tang, Y.M.Xie, Optimal design and modeling of gyroid-based functionally graded cellular structures for additive manufacturing, Comput. Des. 104 (2018) 87–99. https://doi.org/10.1016/J.CAD.2018.06.003.
[83] Polyamide 12 (PA 12) - 3D Printing with Nylon Plastic Fast Radius. https://www.fastradius.com/resources/polyamide-12/.
[84] HP 3D Jet Fusion 4200 - Commercial & Industrial 3D Printer HP Official Site. https://www8.hp.com/us/en/printers/3d-printers/products/multi-jet-fusion-4200.html.
[85] A.Nazir, J.Y.Jeng, A high-speed additive manufacturing approach for achieving high printing speed and accuracy:, Https://Doi.Org/10.1177/0954406219861664. 234 (2019) 2741–2749. https://doi.org/10.1177/0954406219861664.
[86] HP 3D Jet Fusion 500/300 Color 3D Printer | HP Official Site. https://www8.hp.com/us/en/printers/3d-printers/products/multi-jet-fusion-500-300.html.
[87] Sinterit - Manufacturer of compact and industrial SLS 3D printers. https://sinterit.com/.
[88] ABS-like Resin | Phrozen – Prosin Technology Light Curing 3D Printer. https://phrozen3d.com.tw/collections/phrozen-resins/products/abs-like-resin-phrozen?variant=41629540483231.
[89] Ansys | Engineering Simulation Software. https://www.ansys.com/.
[90] HP Multi Jet 3D Printing Technology - The Latest 3D Printing Technology from HP Official Site. https://www8.hp.com/us/en/printers/3d-printers/products/multi-jet-technology.html.
[91] H.J.O’Connor, A.N.Dickson, D.P.Dowling, Evaluation of the mechanical performance of polymer parts fabricated using a production scale multi jet fusion printing process, Addit. Manuf. 22 (2018) 381–387. https://doi.org/10.1016/j.addma.2018.05.035.
[92] D.Manolakos, M.Deja, A.P.Markopoulos, D.Dzienniak, The Influence of the Material Type and the Placement in the Print Chamber on the Roughness of MJF-Printed 3D Objects, Mach. 2022, Vol. 10, Page 49. 10 (2022) 49. https://doi.org/10.3390/MACHINES10010049.
[93] Lisa SLS 3D Printer - Sinterit - Manufacturer of high-quality SLS 3D printers. https://www.sinterit.com/sinterit-lisa/.
[94] P.C.Sun, H.W.Wei, C.H.Chen, C.H.Wu, H.C.Kao, C.K.Cheng, Effects of varying material properties on the load-deformation characteristics of heel cushions, Med. Eng. Phys. 30 (2008) 687–692. https://doi.org/10.1016/j.medengphy.2007.07.010.
[95] Ç.Uyulan, M.Gokasan, Nonlinear Dynamic Characteristics of the Railway Vehicle, Nonlinear Eng. 6 (2017) 123–137. https://doi.org/10.1515/nleng-2016-0070.
[96] A.Nazir, M.Ali, C.H.Hsieh, J.Y.Jeng, Investigation of stiffness and energy absorption of variable dimension helical springs fabricated using multijet fusion technology, Int. J. Adv. Manuf. Technol. 110 (2020) 2591–2602. https://doi.org/10.1007/s00170-020-06061-8.
[97] N.Schmit, M.Okada, Optimal design of nonlinear springs in robot mechanism: simultaneous design of trajectory and spring force profiles, Adv. Robot. 27 (2013) 33–46. https://doi.org/10.1080/01691864.2013.751162.
[98] B.Rivlin, D.Elata, Design of nonlinear springs for attaining a linear response in gap-closing electrostatic actuators, Int. J. Solids Struct. 49 (2012) 3816–3822. https://doi.org/10.1016/j.ijsolstr.2012.08.014.
[99] R.Luo, H.Shi, J.Guo, L.Huang, J.Wang, A nonlinear rubber spring model for the dynamics simulation of a high-speed train, Veh. Syst. Dyn. 58 (2020) 1367–1384. https://doi.org/10.1080/00423114.2019.1624788.
[100] H.A.Navarro, M.P.deSouza Braun, Determination of the normal spring stiffness coefficient in the linear spring–dashpot contact model of discrete element method, Elsevier, 2013. https://doi.org/10.1016/J.POWTEC.2013.05.049.
[101] G.Kuwabara, K.Kono, Restitution coefficient in a collision between two spheres, Jpn. J. Appl. Phys. 26 (1987) 1219–1223. https://doi.org/10.1143/JJAP.26.1230/XML.
[102] E.L.Starostin, G.H.M.van derHeijden, Cascade unlooping of a low-pitch helical spring under tension, J. Mech. Phys. Solids. 57 (2009) 959–969. https://doi.org/10.1016/J.JMPS.2009.02.004.
[103] C.J.Ancker, J.R.Manager, J.N.Goodier, Theory of Pitch and Curvature Corrections for the Helical Spring—I (Tension), J. Appl. Mech. 25 (1958) 471–483. https://doi.org/10.1115/1.4011860.
[104] C.J.Ancker, J.R.Manager, J.N.Goodier, Pitch and Curvature Corrections for Helical Springs, J. Appl. Mech. 25 (1958) 466–470. https://doi.org/10.1115/1.4011859.
[105] V.Kobelev, Disc Springs, in: Durab. Springs, Springer, 2018: pp. 118–126.
[106] K.P.M.Lee, C.Pandelidi, M.Kajtaz, Build orientation effects on mechanical properties and porosity of polyamide-11 fabricated via multi jet fusion, Addit. Manuf. 36 (2020) 101533. https://doi.org/10.1016/J.ADDMA.2020.101533.
[107] S.V.Canchi, R.G.Parker, Parametric instability of a circular ring subjected to moving springs, J. Sound Vib. 293 (2006) 360–379. https://doi.org/10.1016/J.JSV.2005.10.007.
[108] M.R. ul Haq, A.Nazir, S.C.Lin, J.Y.Jeng, Parametric investigation of functionally gradient wave springs designed for additive manufacturing, Int. J. Adv. Manuf. Technol. 119 (2021) 1673–1691. https://doi.org/10.1007/S00170-021-08325-3/FIGURES/22.
[109] (PDF) Performance of EVA foam in running shoes. https://www.researchgate.net/publication/225030841_Performance_of_EVA_foam_in_running_shoes.
[110] A.Nazir, A.-B.Arshad, C.-P.Hsu, J.-Y.Jeng, Effect of Fillets on Mechanical Properties of Lattice Structures Fabricated Using Multi-Jet Fusion Technology, Mater. 2021, Vol. 14, Page 2194. 14 (2021) 2194. https://doi.org/10.3390/MA14092194.
[111] Men’s Phoenix – SPIRA INC. https://spira.com/collections/running-mens/products/mens-phoenix-srnx101?variant=30349469024330
[112] Adidas to release a new version of 3D printed shoe, Alphaedge 4D - 3D Printing Industry, https://3dprintingindustry.com/news/adidas-to-release-a-new-version-of-3d-printed-shoe-alphaedge-4d-155578/.
[113] Carbon Finally Unveils First Commercial CLIP 3D Printer - 3D Printing Industry. https://3dprintingindustry.com/news/carbon3d-finally-unveils-first-commercial-clip-3d-printer-75675/.
[114] H.E.Burton, N.M.Eisenstein, B.M.Lawless, P.Jamshidi, M.A.Segarra, O.Addison, D.E.T.Shepherd, M.M.Attallah, L.M.Grover, S.C.Cox, The design of additively manufactured lattices to increase the functionality of medical implants, Mater. Sci. Eng. C. 94 (2019) 901–908. https://doi.org/10.1016/J.MSEC.2018.10.052.
[115] X.Z.Zhang, M.Leary, H.P.Tang, T.Song, M.Qian, Selective electron beam manufactured Ti-6Al-4V lattice structures for orthopedic implant applications: Current status and outstanding challenges, Curr. Opin. Solid State Mater. Sci. 22 (2018) 75–99. https://doi.org/10.1016/J.COSSMS.2018.05.002.
[116] J.C.Najmon, S.Raeisi, A.Tovar, Review of additive manufacturing technologies and applications in the aerospace industry, Addit. Manuf. Aerosp. Ind. (2019) 7–31. https://doi.org/10.1016/B978-0-12-814062-8.00002-9.
[117] M.Helou, S.Kara, Design, analysis and manufacturing of lattice structures: an overview, Https://Doi.Org/10.1080/0951192X.2017.1407456. 31 (2017) 243–261. https://doi.org/10.1080/0951192X.2017.1407456.
[118] L.Chougrani, J.P.Pernot, P.Véron, S.Abed, Parts internal structure definition using non-uniform patterned lattice optimization for mass reduction in additive manufacturing, Eng. Comput. 35 (2019) 277–289. https://doi.org/10.1007/S00366-018-0598-2/FIGURES/14.
[119] H.Friedrich, S.Schumann, Research for a “new age of magnesium” in the automotive industry, J. Mater. Process. Technol. 117 (2001) 276–281. https://doi.org/10.1016/S0924-0136(01)00780-4.
[120] B.K.Nagesha, V.Dhinakaran, M.Varsha Shree, K.P.Manoj Kumar, D.Chalawadi, T.Sathish, Review on characterization and impacts of the lattice structure in additive manufacturing, Mater. Today Proc. 21 (2020) 916–919. https://doi.org/10.1016/J.MATPR.2019.08.158.
[121] S.Yu, J.Sun, J.Bai, Investigation of functionally graded TPMS structures fabricated by additive manufacturing, Mater. Des. 182 (2019) 108021. https://doi.org/10.1016/J.MATDES.2019.108021.
[122] B.Bahrami Babamiri, H.Askari, K.Hazeli, Deformation mechanisms and post-yielding behavior of additively manufactured lattice structures, Mater. Des. 188 (2020) 108443. https://doi.org/10.1016/J.MATDES.2019.108443.
[123] P.Köhnen, C.Haase, J.Bültmann, S.Ziegler, J.H.Schleifenbaum, W.Bleck, Mechanical properties and deformation behavior of additively manufactured lattice structures of stainless steel, Mater. Des. 145 (2018) 205–217. https://doi.org/10.1016/J.MATDES.2018.02.062.
[124] O.Al-Ketan, R.Rowshan, R.K.Abu Al-Rub, Topology-mechanical property relationship of 3D printed strut, skeletal, and sheet based periodic metallic cellular materials, Addit. Manuf. 19 (2018) 167–183. https://doi.org/10.1016/J.ADDMA.2017.12.006.
[125] S.Daynes, S.Feih, W.F.Lu, J.Wei, Design concepts for generating optimised lattice structures aligned with strain trajectories, Comput. Methods Appl. Mech. Eng. 354 (2019) 689–705. https://doi.org/10.1016/J.CMA.2019.05.053.
[126] J.Wu, W.Wang, X.Gao, Design and Optimization of Conforming Lattice Structures, IEEE Trans. Vis. Comput. Graph. 27 (2021) 43–56. https://doi.org/10.1109/TVCG.2019.2938946.
[127] Fusion 360 with Netfabb Get Prices & Buy Netfabb Autodesk. https://www.autodesk.com/products/netfabb/overview.
[128] MATLAB - MathWorks - MATLAB & Simulink. https://www.mathworks.com/products/matlab.html?s_tid=hp_ff_p_matlab.
[129] I.Maskery, L.Sturm, A.O.Aremu, A.Panesar, C.B.Williams, C.J.Tuck, R.D.Wildman, I.A.Ashcroft, R.J.M.Hague, Insights into the mechanical properties of several triply periodic minimal surface lattice structures made by polymer additive manufacturing, Polymer (Guildf). 152 (2018) 62–71. https://doi.org/10.1016/J.POLYMER.2017.11.049.
[130] Z.Dong, X.Zhao, Application of TPMS structure in bone regeneration, Eng. Regen. 2 (2021) 154–162. https://doi.org/10.1016/J.ENGREG.2021.09.004.
[131] Z.A.Qureshi, S.A.B.Al-Omari, E.Elnajjar, O.Al-Ketan, R.A.Al-Rub, Using triply periodic minimal surfaces (TPMS)-based metal foams structures as skeleton for metal-foam-PCM composites for thermal energy storage and energy management applications, Int. Commun. Heat Mass Transf. 124 (2021) 105265. https://doi.org/10.1016/J.ICHEATMASSTRANSFER.2021.105265.
[132] S.Catchpole-Smith, R.R.J.Sélo, A.W.Davis, I.A.Ashcroft, C.J.Tuck, A.Clare, Thermal conductivity of TPMS lattice structures manufactured via laser powder bed fusion, Addit. Manuf. 30 (2019) 100846. https://doi.org/10.1016/J.ADDMA.2019.100846.
[133] O.Al-Ketan, R.K.Abu Al-Rub, U.Abu Dhabi, A.Dhabi, MSLattice: A free software for generating uniform and graded lattices based on triply periodic minimal surfaces, Mater. Des. Process. Commun. 3 (2021) e205. https://doi.org/10.1002/MDP2.205.
[134] O.Sigmund, A 99 line topology optimization code written in Matlab, Struct. Multidiscip. Optim. 2001 212. 21 (2014) 120–127. https://doi.org/10.1007/S001580050176.
[135] R.Y.Zhong, X.Xu, E.Klotz, S.T.Newman, Intelligent Manufacturing in the Context of Industry 4.0: A Review, Engineering. 3 (2017) 616–630. https://doi.org/10.1016/J.ENG.2017.05.015.
[136] D.McFarlane, S.Sarma, J.L.Chirn, C.Y.Wong, K.Ashton, Auto-ID systems and intelligent manufacturing control, Eng. Appl. Artif. Intell. 16 (2003) 365–376. https://doi.org/10.1016/S0952-1976(03)00077-0.
[137] I.Gibson, D.Rosen, B.Stucker, M.Khorasani, Software for Additive Manufacturing, Addit. Manuf. Technol. (2021) 491–524. https://doi.org/10.1007/978-3-030-56127-7_17.
[138] B.H.Jared, M.A.Aguilo, L.L.Beghini, B.L.Boyce, B.W.Clark, A.Cook, B.J.Kaehr, J.Robbins, Additive manufacturing: Toward holistic design, Scr. Mater. 135 (2017) 141–147. https://doi.org/10.1016/J.SCRIPTAMAT.2017.02.029.
[139] A.Gleadall, FullControl GCode Designer: Open-source software for unconstrained design in additive manufacturing, Addit. Manuf. 46 (2021) 102109. https://doi.org/10.1016/J.ADDMA.2021.102109.
[140] K.Rajaguru, T.Karthikeyan, V.Vijayan, Additive manufacturing – State of art, Mater. Today Proc. 21 (2020) 628–633. https://doi.org/10.1016/J.MATPR.2019.06.728.
[141] B.Blakey-Milner, P.Gradl, G.Snedden, M.Brooks, J.Pitot, E.Lopez, M.Leary, F.Berto, A.duPlessis, Metal additive manufacturing in aerospace: A review, Mater. Des. 209 (2021) 110008. https://doi.org/10.1016/J.MATDES.2021.110008.
[142] M.Bhuvanesh Kumar, P.Sathiya, Methods and materials for additive manufacturing: A critical review on advancements and challenges, Thin-Walled Struct. 159 (2021) 107228. https://doi.org/10.1016/J.TWS.2020.107228.
[143] Wave Spring vs. Coil Spring Smalley. https://www.smalley.com/blog/wave-spring-vs-coil-spring.
[144] Top 6 reasons to use a wave spring. https://www.designworldonline.com/top-6-reasons-to-use-a-wave-spring/.
[145] C.Scheuer, E.Boot, N.Carse, A.Clardy, J.Gallagher, S.Heck, S.Marron, L.Martinez-Alvarez, D.Masarykova, P.Mcmillan, F.Murphy, E.Steel, H.VanEkdom, H.Vecchione, Disentangling inclusion in physical education lessons: Developing a resource toolkit for teachers, Phys. Educ. Sport Child. Youth with Spec. Needs Res. – Best Pract. – Situat. (2021) 343–354. https://doi.org/10.2/JQUERY.MIN.JS.
[146] US9039766B1 - Wave spring for a spinal implant - Google Patents. https://patents.google.com/patent/US9039766?oq=wave+spring.
[147] M.R. ul Haq, A.Nazir, S.C.Lin, J.Y.Jeng, Parametric investigation of functionally gradient wave springs designed for additive manufacturing, Int. J. Adv. Manuf. Technol. (2021) 1–19. https://doi.org/10.1007/S00170-021-08325-3/FIGURES/22.
[148] Welcome to Python.org, (n.d.). https://www.python.org/.
[149] Fusion 360 3D CAD, CAM, CAE & PCB Cloud-Based Software Autodesk. https://www.autodesk.com/products/fusion-360/overview.
[150] Visual Studio Code - Code Editing. Redefined. https://code.visualstudio.com/.
[151] What is FDM 3D printing Hubs. https://www.hubs.com/knowledge-base/what-is-fdm-3d-printing/.
[152] Stereolithography (SLA) 3D Printing Guide. https://formlabs.com/blog/ultimate-guide-to-stereolithography-sla-3d-printing/.
[153] HP Multi Jet Fusion 3D Printing Technology - Powder 3D Printer HP Official Site.https://www.hp.com/us-en/printers/3d-printers/products/multi-jet-technology.html.
[154] M.R. ulHaq, A.Nazir, S.C.Lin, J.Y.Jeng, Parametric investigation of functionally gradient wave springs designed for additive manufacturing, Int. J. Adv. Manuf. Technol. (2021) 1–19. https://doi.org/10.1007/S00170-021-08325-3/FIGURES/22.
[155] A.BinArshad, A.Nazir, J.Y.Jeng, Design and performance evaluation of multi-helical springs fabricated by Multi Jet Fusion additive manufacturing technology, Int. J. Adv. Manuf. Technol. 118 (2022) 195–206. https://doi.org/10.1007/S00170-021-07756-2/FIGURES/13.
[156] US9039766B1 - Wave spring for a spinal implant - Google Patents. https://patents.google.com/patent/US9039766B1/en.