The chin bar of a motorcycle helmet protects the rider from facial and head injuries. To evaluate the protective performance of chin bars against head injuries from facial impacts, an explicit finite element method was used to simulate the Snell Memorial Foundation test and a proposed drop test. The maximum acceleration and Head Injury Criterion (HIC) were employed to assess the impact-absorbing capability of the chin bar. The results showed that the proposed approach should be more practical than the Snell test, and provided more information for improving the chin bar design to protect against head injuries. The shell stiffness was important in determining the protective ability of the chin bar, but a chin bar with only an outer shell and comfort foam offered inadequate protection. An energy-absorbing liner was essential to increase the protective performance of the chin bar and the liner density should be denser than that used in the cranial portion of the helmet. For the chin bar with energy-absorbing liner, a shell design that is less stiff would provide better protection. [S0148-0731(00)01206-1]
Issue Section:
Technical Papers
Keywords:
Head Injury,
Helmet,
Chin Bar,
Finite Element Analysis,
finite element analysis,
impact (mechanical),
biomechanics,
health hazards,
safety,
accidents
Topics:
Finite element analysis,
Shells,
Stiffness,
Wounds,
Density,
Design,
Safety,
Accidents,
Finite element model
1.
Watson
, G. S.
, Zador
, P. L.
, and Wilks
, A.
, 1980
, “The Repeal of Helmet Use Laws and Increased Motorcyclist Mortality in the United States: 1975–1978
,” American J. Public Health
, 70
, pp. 579
–585
.2.
McSwain
, Jr., N. E.
, and Petrucelli
, E.
, 1984
, “Medical Consequences of Motorcycle Helmet Nonusage
,” J. Trauma
, 24
, pp. 233
–236
.3.
Tsai
, Y. J.
, Wang
, J. D.
, and Huang
, W. F.
, 1995
, “Case-Control Study of the Effectiveness of Different Types of Helmets for the Prevention of Head Injuries Among Motorcycle Riders in Taipei, Taiwan
,” Am. J. Epidemiol.
, 142
, pp. 974
–981
.4.
FMVSS 218, 1992, “Motorcycle Helmets,” Federal Motor Vehicle Safety Standard, Washington.
5.
Snell Memorial Foundation, 1995, “Standard for Protective Headgear,” North Highlands, CA.
6.
British Standard 6658, 1985, “Protective Helmets for Vehicle Users,” British Standard Institution, London.
7.
E.C.E. R 22, 1995, “Uniform Provisions Concerning the Approval of Protective Helmets and of Their Visors for Drivers and Passengers of Motorcycles and Mopeds,” Geneva.
8.
JIS T 8133, 1994, “Protective Helmets for Vehicle Users,” Japanese Industrial Standard, Tokyo.
9.
Hurt, H. H., Jr., Ouellet, J. V., and Thom, D. R., 1981, “Motorcycle Accident Cause Factors and Identification of Countermeasures,” U.S. Department Transportation Report DOT HS-805 862.
10.
Matzsch
, T.
, and Karlsson
, B.
, 1986
, “Moped and Motorcycle Accidents— Similarities and Discrepancies
,” J. Trauma
, 26
, pp. 538
–543
.11.
Sood
, S.
, 1988
, “Survey of Factors Influencing Injury Among Riders Involved in Motorized Two-Wheeler Accidents in India: A Prospective Study of 302 Cases
,” J. Trauma
, 28
, pp. 530
–534
.12.
Bachulis
, B. L.
, Sangster
, W.
, Gorrell
, G. W.
, and Long
, W. B.
, 1988
, “Patterns of Injury in Helmeted and Nonhelmeted Motorcyclists
,” Am. J. Surg.
, 155
, pp. 708
–711
.13.
Johnson
, R. M.
, McCarthy
, M. C.
, Miller
, S. F.
, and Peoples
, J. B.
, 1995
, “Craniofacial Trauma in Injured Motorcyclists: the Impact of Helmet Usage
,” J. Trauma
, 38
, pp. 876
–878
.14.
Lee
, M. C.
, Chiu
, W. T.
, Chang
, L. T.
, Liu
, S. C.
, and Lin
, S. H.
, 1995
, “Craniofacial Injuries in Unhelmeted Riders of Motorbikes
,” Injury
, 26
, pp. 467
–470
.15.
Gopalakrishna
, G.
, Peak-Asa
, C.
, and Kraus
, J. F.
, 1998
, “Epidemiologic Features of Facial Injuries Among Motorcyclists
,” Annals of Emergency Medicine
, 32
, pp. 425
–430
.16.
Kingsbury, H. B., and Rohr, P. R., 1981, “Structure Characteristics of Motorcycle Helmets,” SAE Paper No. 810372.
17.
Gale
, A.
, and Mills
, N. J.
, 1985
, “Effect of Polystyrene Foam Liner Density on Motorcycle Helmet Shock Absorption
,” Plast. Rubber Proc. Appl.
, 5
, pp. 101
–108
.18.
Mills
, N. J.
, and Gilchrist
, A.
, 1991
, “The Effectiveness of Foams in Bicycle and Motorcycle Helmets
,” Accident Anal. Prev.
, 23
, pp. 153
–163
.19.
Gilchrist
, A.
, and Mills
, N. J.
, 1994
, “Impact Deformation of ABS and GRP Motorcycle Helmet Shells
,” Plast. Rubber Proc. Appl.
, 21
, pp. 141
–150
.20.
Gilchrist
, A.
, and Mills
, N. J.
, 1994
, “Modelling of the Impact Response of Motorcycle Helmets
,” Int. J. Impact Eng.
, 15
, pp. 201
–217
.21.
Yettram
, A. L.
, Godfrey
, N. P. M.
, and Chinn
, B. P.
, 1994
, “Materials for Motorcycle Crash Helmets—A Finite Element Parametric Study
,” Plast. Rubber Proc. Appl.
, 22
, pp. 215
–221
.22.
Vaughan
, R. G.
, 1977
, “Motorcycle Helmets and Facial Injuries
,” Med. J. Aust.
, 29
, pp. 125
–127
.23.
Cannell
, H.
, King
, J. B.
, and Winch
, R. D.
, 1982
, “Head and Facial Injuries After Low-Speed Motor-Cycle Accidents
,” Br. J. Oral Surg.
, 20
, pp. 183
–191
.24.
Cooter
, R. D.
, David
, D. J.
, McLean
, A. J.
, and Simpson
, D. A.
, 1988
, “Helmet-Induced Skull Base Fracture in a Motorcyclist
,” Lancet
, 16
, pp. 84
–85
.25.
Cooter
, R. D.
, 1990
, “Computed Tomography in the Assessment of Protective Helmet Deformation
,” J. Trauma
, 30
, pp. 55
–68
.26.
Otte, D., 1991, “Technical Demands on Safety in the Design of Crash Helmets for Biomechanical Analysis of Real Accident Situations,” Proc. 35th Stapp Car Crash Conference, San Diego, CA, pp. 335–349.
27.
Chang
, L. T.
, Chang
, C. H.
, and Chang
, G. L.
, 1999
, “Experimental Evaluation of Chin Bar on Head Injury in Facial Impact
,” JSME Int. J., Ser. A
, 42
, pp. 294
–300
.28.
Versace, J., 1971, “A Review of the Severity Index,” Proc. 15th Stapp Car Crash Conference, New York.
29.
Hallquist, J. O., “User’s Manual for LS-DYNA3D LSTC Lab.,” Version 940, USA, 1997.
30.
Waterman, N. A., and Ashby, M. F., 1997, The Materials Selector, Chapman and Hall, London.
31.
FMVSS 208, 1993, “Occupant Crash Protection,” Federal Motor Vehicle Safety Standard, Washington.
32.
Simpson
, D. A.
, Blumbergs
, P. C.
, Cooter
, R. D.
, Kilminster
, M.
, McLean
, A. J.
, and Scott
, G.
, 1989
, “Pontomedullary Tears and Other Gross Brainstem Injuries After Vehicular Accidents
,” J. Trauma
, 29
, pp. 1519
–1525
.Copyright © 2000
by ASME
You do not currently have access to this content.
