Research Papers: FORMING

Thermoforming and Structural Analysis of Combat Helmets

[+] Author and Article Information
Bruce K. Cartwright

Pacific Engineering Systems International,
277-279 Broadway,
Glebe, New South Wales 2037, Australia
e-mail: brucec@esi.com.au

N. Lex Mulcahy

Pacific Engineering Systems International,
277-279 Broadway,
Glebe, New South Wales 2037, Australia
e-mail: lexm@esi.com.au

Allen O. Chhor

Pacific Engineering Systems International,
277-279 Broadway,
Glebe, New South Wales 2037, Australia
e-mail: allenc@esi.com.au

Stuart G. F. Thomas

Defence Materials Technology Centre Limited,
Level 2, 24 Wakefield Street,
Hawthorn, Victoria 3122, Australia
e-mail: stuart.thomas@vcamm.com.au

Madhusudan Suryanarayana

Defence Materials Technology Centre Limited,
Level 2, 24 Wakefield Street,
Hawthorn, Victoria 3122, Australia
e-mail: madhusudan.suryanarayana@deakin.edu.au

James D. Sandlin

Defence Materials Technology Centre Limited,
Level 2, 24 Wakefield Street,
Hawthorn, Victoria 3122, Australia
e-mail: james.sandlin@vcamm.com.au

Ian G. Crouch

Defence Materials Technology Centre Limited,
Level 2, 24 Wakefield Street,
Hawthorn, Victoria 3122, Australia
e-mail: ianarmoursolutions@gmail.com

Minoo Naebe

Defence Materials Technology Centre Limited,
Level 2, 24 Wakefield Street,
Hawthorn, Victoria 3122, Australia
e-mail: minoo.naebe@deakin.edu.au

1Corresponding author.

Contributed by the Manufacturing Engineering Division of ASME for publication in the JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING. Manuscript received December 20, 2014; final manuscript received July 24, 2015; published online September 4, 2015. Assoc. Editor: Yannis Korkolis.

J. Manuf. Sci. Eng 137(5), 051011 (Sep 04, 2015) (9 pages) Paper No: MANU-14-1688; doi: 10.1115/1.4031154 History: Received December 20, 2014; Revised July 24, 2015

To reduce combat casualties, military helmets are designed to provide protection against projectiles. Modern combat helmets are constructed of relatively lightweight composite materials that provide ballistic protection to the soldier. The manufacture of most composite helmets is labor intensive and involves the manual application and smoothing of individual layers of reinforcement to a concave mold surface. The recently developed double diaphragm deep drawing thermoforming process turns as-purchased, flat-form composite materials into structurally efficient three-dimensional shapes. Using this process, prototype shells have been produced and subsequently tested structurally. The success of the outcome has been greatly assisted through the use of specialized virtual prototyping techniques to provide insight into the thermoforming process of the shells and subsequently their structural performance by accounting for the actual fiber orientations of those finished shells.

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Kulkarni, S. G. , Gao, X.-L. , Horner, S. E. , Zheng, J. Q. , and David, N. V. , 2013, “Ballistic Helmets—Their Design, Materials, and Performance Against Traumatic Brain Injury,” Compos. Struct., 101, pp. 313–331. [CrossRef]
Crye Airframe Helmet, “The AirFrame™ Ballistic Helmet,” Last accessed Nov. 19, 2014, http://www.cryeprecision.com/P-HLMM0106LG0/Airframe%E2%84%A2-Helmet
Ops-Core Helmet, “Sentry Helmet (XP),” Last accessed Nov. 19, 2014, http://www.ops-core.com/Sentry_Helmet_XP__P97C6.cfm
LAND 149 Lightweight Ballistic Armour, 2005, Department of Defence Capability and Technology Demonstrator (CTD) Program, DSTO, Port Melbourne, VIC Australia.
Crouch, I. G. , 2013, “NG Combat Helmets,” DMTC Annual Conference, Canberra, Australia.
Prevorsek, D. C. , Harpell, G. A. , Kwon, Y. D. , Li, H. L. , and Young, S. , 1988, “Ballistic Armour From Extended Polyethylene Chain Fibres,” 33rd SAMPE Symposium, Anaheim, CA, Mar. 7–10, Vol. 33, pp. 1685–1696.
GL-PD-09-04, 2013, Purchase Description (PD) for Enhanced Combat Helmet, Revision K, United States Marine Corp, United States Department of Defense, Washington, DC.
Honeywell, “Descriptions of Honeywell Spectra Shield Products,” Last accessed Nov. 19, 2014, http://www.honeywell-advancedfibersandcomposites.com/product/tag/composite-materials/
Honeywell, “Descriptions of Honeywell Products for Body Armour Applications,” Last accessed Nov. 19, 2014, http://www.bodyarmornews.com/tag/honeywell
DSM Dyneema, “Descriptions of Dyneema Products,” Last accessed Nov. 19, 2014, http://www.dyneema.com/apac/
DuPont Tensylon, “Descriptions of Armour Protection Systems,” Last accessed Nov. 19, 2014, http://www.dupont.com/products-and-services/personal-protective-equipment/vehicle-armor/products/dupont-tensylon.html
Lebrun, G. , Bureau, M. N. , and Denault, J. , 2003, “Evaluation of Bias-Extension and Picture-Frame Test Methods for the Measurement of Intraply Shear Properties of PP/Glass Commingled Fabrics,” Compos. Struct., 61(4), pp. 341–352. [CrossRef]
Cartwright, B. K. , de Luca, P. , Wang, J. , Stellbrink, K. , and Paton, R. , 1999, “Some Proposed Experimental Tests for Use in Finite Element Simulation of Composite Forming,” 12th International Conference on Composite Materials (ICCM-12), Paris, France, July 5–9, Paper 582.
ESI, 2013, Composite Solution Suite User Manual, ESI Group, Paris, France.
ESI, 2013, Virtual Performance Solution User Manual, ESI Group, Paris, France.
Zhong, Z.-H. , 1993, Finite Element Procedures for Contact-Impact Problems, Oxford University Press, Oxford, UK.
Hiermaier, S. , 2008, Structures Under Crash and Impact: Continuum Mechanics, Discretization and Experimental Characterization, Springer, New York.
Wu, S. , and Gu, L. , 2012, Introduction to the Explicit Finite Element for Nonlinear Transient Dynamics, Wiley, Hoboken, NJ.
De Luca, P. , Pickett, A. K. , Queckborner, T. , and Johnson, A. F. , 1995, “Development Validation and First Industrial Numerical Results of a Finite Element Code to Simulate the Thermoforming Process,” 4th International Conference on Automated Composites (ICAC’95), Nottingham, UK, Sept. 6–7, Vol. I, pp. 183–193.
Pickett, A. K. , Queckborner, T. , de Luca, P. , and Haug, E. , 1995, “An Explicit Finite Element Solution for the Forming Prediction of Continuous Fibre-Reinforced Thermoplastic Sheets,” Compos. Manuf., 6(3–4), pp. 237–244. [CrossRef]
Pickett, A. K. , Cunningham, J. E. , Johnson, A. F. , Lefebure, P. , de Luca, P. , Mallon, P. , Sunderland, P. , O'Bradaigh, C. , Vodermayer, A. M. , and Werner, W. , 1996, “Numerical Techniques for the Pre-Heating and Forming Simulation of Continuous Fibre Reinforced Thermoplastics,” 17th SAMPE Europe Conference and Exhibit, Basel, Switzerland, May 28–30, Vol. 17, pp. 353–364.
Johnson, A. F. , and Pickett, A. K. , 1996, “Numerical Simulation of the Forming Process in Long Fibre Reinforced Thermoplastic,” CADCOMP ‘96, Udine, Italy, July 1–3, pp. 233–242.
de Luca, P. , Lefebure, P. , and Pickett, A. K. , 1998, “Numerical and Experimental Investigation of Some Press Forming Parameters of Two Fibre Reinforced Thermoplastics: APC2-AS4 and PEI-CETEX,” Composites, Part A, 29(1–2), pp. 101–110. [CrossRef]
Pickett, A. K. , 2002, “Review of Finite Element Methods Applied to Manufacturing and Failure Prediction in Composite Structures,” Appl. Compos. Mater., 9(1), pp. 43–58. [CrossRef]
Creech, G. , Pickett, A. K. , and Greve, L. , 2003, “Finite Element Modelling of Non-Crimp Fabrics for Draping Simulation,” 6th International ESAFORM Conference on Material Forming, Salerno, Italy, Apr. 28–30, pp. 863–866.
Cartwright, B. , Chhor, A. , Howlett, S. , McGuckin, D. , Paton, R. , Ye, L. , and Yu, X. , 2003, “Industrially Robust Modelling of Viscous Friction Effects in Composites,” EuroPAM, Mainz, Germany, Oct. 16–17.
Yu, X. , Ye, L. , Mai, Y.-W. , Cartwright, B. , McGuckin, D. , and Paton, R. , 2005, “Finite Element Simulations of the Doublediaphragm Forming Process: Comparisons With Experimental Trials,” Revue Europeenne des Elements Finis, 14(6–7), pp. 633–651. [CrossRef]
Pickett, A. K. , Creech, G. , and de Luca, P. , 2005, “Simplified and Advanced Simulation Methods for Prediction of Fabric Draping,” Revue Europeenne des Elements Finis, 14(6–7), pp. 677–691. [CrossRef]
Brite-Euram, 1992–1996, “Industrial Press Forming of Continuous Fibre-Reinforced Thermoplastic Sheets and the Development of Numerical Simulation Tools,” Brite-Euram Project, Contract No. BE-5092.
O'Bradaigh, C. M. , McGuinness, G. B. , and Pipes, R. B. , 1993, “Numerical Analysis of Stresses and Deformations in Composite Materials Sheet Forming: Central Indentation of a Circular Sheet,” Compos. Manuf., 4(2), pp. 67–83. [CrossRef]
Boise, P. , Borr, M. , Buer, K. , and Cherouat, A. , 1997, “Finite Element Simulations of Textile Composite Forming Including the Biaxial Fabric Behaviour,” Composites, Part B, 28(4), pp. 453–464. [CrossRef]
El Khaldi, F. , Ni, R. , Culiere, P. , Ullrich, P. , and Terrez Aboitiz, C. , 2010, “Recent Integration Achievements in Virtual Prototyping for the Automotive Industry,” FISITA World Automotive Congress, Budapest, Hungary, May 30–June 4, Paper No. F2010-C-206.
Middendorf, P. , Van den Broucke, B. , Lomov, S. V. , Verpoest, I. , and De Luca, P. , 2007, “Integrated Simulation Approach for Fabric Textile Composites,” SAMPE Europe Technical Conference, SETEC 2007, Madrid, Spain, Sept. 6–7, pp. 213–222.
Walsh, S. M. , Scott, B. , Spagnuolo, D. , and Wolbert, J. , 2008, “The Development of UHMWPE Prototype Helmets for Improved Ballistic Mass Efficiency,” 53rd SAMPE Symposium, Long Beach, CA, May 18–22, Vol. 53.
Fischer, H. , 2014, A Guide to U.S. Military Casualty Statistics, Operation Inherent Resolve, Operation New Dawn, Operation Iraqi Freedom, and Operation Enduring Freedom, U.S. Congressional Research Service, Washington, DC.
Choi, H.-Y. , 2001, “Numerical Human Head Model for Traumatic Injury Assessment,” KSME Int. J., 15(7), pp. 995–1001.
Haug, E. , Choi, H.-Y. , Robin, S. , and Beaugonin, M. , 2004, “Human Models for Crash and Impact Simulation,” Handbook of Numerical Analysis (Computational Models for the Human Body, Vol. 12), Elsevier, Amsterdam, The Netherlands.


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Fig. 1

Numerical model of a flexure test

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Fig. 2

The numerical modeling of the initial process variables showed that wrinkles were likely to develop in the formed part. This was confirmed by experiment.

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Fig. 3

Varying the process parameters in the simulations enabled the conditions for a wrinkle-free helmet to be developed

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Fig. 4

Angles through which the fibers were sheared due to the forming process

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Fig. 5

FE model of lateral compression test setup

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Fig. 6

Spectra Shield SR-3136 helmet produced from the newly commissioned preproduction prototype D4 machine

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Fig. 7

Spectra Shield II SR-3130 helmet shell in test jig: (a) vertical compression and (b) lateral compression

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Fig. 8

Force against displacement for side-to-side compression of the helmet—test, the analysis with assumed-orthogonal fiber directions and the analysis with formed fiber directions

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Fig. 9

Spectra Shield 3136 ply damage

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Fig. 10

Tied interface stress–displacement curve



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