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Technical Brief

Inertial Properties of Football Helmets

[+] Author and Article Information
James R. Funk

Biocore LLC,
1621 Quail Run,
Charlottesville, VA 22911
e-mail: jfunk@biocorellc.com

Roberto E. Quesada

Biocore LLC,
1621 Quail Run,
Charlottesville, VA 22911
e-mail: rquesada@biocorellc.com

Alexander M. Miles

Biocore LLC,
1621 Quail Run,
Charlottesville, VA 22911
e-mail: amiles@biocorellc.com7

Jeff R. Crandall

Biocore LLC,
1621 Quail Run,
Charlottesville, VA 22911
e-mail: jcrandall@biocorellc.com

Manuscript received February 6, 2017; final manuscript received February 27, 2018; published online April 30, 2018. Assoc. Editor: Barclay Morrison.

J Biomech Eng 140(6), 064501 (Apr 30, 2018) (7 pages) Paper No: BIO-17-1046; doi: 10.1115/1.4039673 History: Received February 06, 2017; Revised February 27, 2018

The inertial properties of a helmet play an important role in both athletic performance and head protection. In this study, we measured the inertial properties of 37 football helmets, a National Operating Committee on Standards for Athletic Equipment (NOCSAE) size 7¼ headform, and a 50th percentile male Hybrid III dummy head. The helmet measurements were taken with the helmets placed on the Hybrid III dummy head. The center of gravity and moment of inertia were measured about six axes (x, y, z, xy, yz, and xz), allowing for a complete description of the inertial properties of the head and helmets. Total helmet mass averaged 1834±231 g, split between the shell (1377±200 g) and the facemask (457±101 g). On average, the football helmets weighed 41±5% as much as the Hybrid III dummy head. The center of gravity of the helmeted head was 1.1±3.0 mm anterior and 10.3±1.9 mm superior to the center of gravity of the bare head. The moment of inertia of the helmeted head was approximately 2.2±0.2 times greater than the bare head about all axes.

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References

Gallagher, H. L. , and Caldwell, E. , 2008, “ Neck Muscle Fatigue Resulting From Prolonged Wear of Weighted Helmets,” Air Force Research Laboratory, Wright-Patterson AFB, OH, Report No. AFRL-RH-WP-TR-2008-0096.
Gaur, S. J. , Joshi, V. V. , Aravindakshan, B. , and Aravind, A. S. , 2013, “ Determination of Helmet CG and Evaluation of Neck Injury Potentials Using ‘Knox Box Criteria’ and Neck Torque Limits,” Ind. J. Aerosp. Med., 57(1), pp. 37–44.
Allen, D. , Buckland, B. , and Lastnik, A. , 1982, “ Method for Determining the Center of Mass of Helmets,” United States Army Natick Research and Development Center, Natick, MA, Technical Report No. AD-A141 633.
Njus, G. O. , Liu, Y. K. , and Nye, T. A. , 1984, “ The Inertial and Geometric Properties of Helmets,” Med. Sci. Sports Exercise, 16(5), pp. 498–505. [CrossRef]
Settecerri, J. J. , Mckenzie, J. , Privitzer, E. , and Beecher, R. M. , 1986, “ Mass Properties and Inertial Loading Effects of Head Encumbering Devices,” 24th Annual SAFE Symposium, San Antonio, TX, Dec. 11–13, pp. 276–282.
Thornton, J. M. , and Zoborowski, D. J. , 1992, “ Mass Properties Test Procedure for Manikin Headforms and Helmet Systems,” Naval Air Systems Command, Washington, DC, Report No. NAWCADWAR-92092-60.
Funk, J. R. , Cormier, J. C. , Bain, C. E. , Guzman, H. , and Bonugli, E. , 2009, “ Validation and Application of a Methodology to Calculate Head Accelerations and Neck Loading in Soccer Ball Impacts,” SAE Paper No. 2009-01-0251.
Kaleps, I. , and Whitestone, J. , 1988, “ Hybrid III Geometrical and Inertial Properties,” SAE Paper No. 880638.
Viano, D. C. , and Halstead, D. , 2012, “ Change in Size and Impact Performance of Football Helmets From the 1970s to 2010,” Ann. Biomed. Eng., 40(1), pp. 175–184. [CrossRef] [PubMed]

Figures

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Fig. 1

Photograph of a center of gravity measurement of a helmeted head in configuration 5

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Fig. 2

Summary of measurement configurations

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Fig. 3

Helmets sorted in order of increasing helmet shell mass

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Fig. 4

Center of gravity measurements (generic helmet outline shown)

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Fig. 5

Shell and facemask components of helmet center of gravity (generic helmet outline shown)

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Fig. 6

Helmets sorted in order of increasing sagittal plane (Iy) moment of inertia

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Fig. 7

Helmet moment of inertia versus mass

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