0
research-article

Differences in Impact Performance of Bicycle Helmets During Oblique Impacts

[+] Author and Article Information
Megan L Bland

Department of Biomedical Engineering and Mechanics, Virginia Tech 440 Kelly Hall, 325 Stanger Street Blacksburg, VA 24061
mbland27@vt.edu

Craig McNally

Center for Injury Biomechanics, Virginia Tech 2280 Kraft Drive VCOM II Building Blacksburg, Virginia 24060
cmcnally@vt.edu

Steven Rowson

Department of Biomedical Engineering and Mechanics, Virginia Tech 343 Kelly Hall, 325 Stanger Street Blacksburg, VA 24061
rowson@vt.edu

1Corresponding author.

ASME doi:10.1115/1.4040019 History: Received August 18, 2017; Revised April 10, 2018

Abstract

Cycling is a leading cause of sport-related head injuries in the U.S. Although bicycle helmets must comply with standards limiting head acceleration in severe impacts, helmets are not evaluated under more common, concussive-level impacts, and limited data are available indicating which helmets offer superior protection. Further, standards evaluate normal impacts, while real-world cyclist head impacts are oblique - involving normal and tangential velocities. The objective of this study was to investigate differences in protective capabilities of ten helmet models under common real-world accident conditions. Oblique impacts were evaluated through drop tests onto an angled anvil at common cyclist head impact velocities and locations. Linear and rotational accelerations were evaluated and related to concussion risk, which was then correlated with design parameters. Significant differences were observed in linear and rotational accelerations between models, producing concussion risks spanning >50% within single impact configurations. Risk differences were more attributable to linear acceleration, as rotational varied less between models. At the temporal location, shell thickness, vent configuration, and radius of curvature were found to influence helmet effective stiffness. This should be optimized to reduce impact kinematics. At the frontal, helmet rim location, liner thickness tapered off for some helmets, likely due to lack of standards testing at this location. This is a frequently impacted location for cyclists, suggesting that the standards testable area should be expanded to include the rim. These results can inform manufacturers, standards bodies, and consumers alike, aiding the development of improved bicycle helmet safety.

Copyright (c) 2018 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In