International Journal of Automotive Technology

, Volume 19, Issue 6, pp 1041–1048 | Cite as

Design for Headrest Including Guides Slot to Reduce the Neck Force in Rear End Impact

  • YunSik Yang
  • YoungShin Kim
  • EuySik JeonEmail author


Whiplash injuries are one of the most common injuries reported in automotive rear end collisions. Automobile seat back and head restraints play a role in reducing neck injuries during low speed rear end collisions. Currently, many studies are being conducted on ways to reduce neck injuries. These deal with the design parameters that cause neck injuries and do not address the design of the head restraint connection structure. In this paper, we analyze the various trajectories of the headrest and propose a new design for a connection structure that can move along the corresponding trajectory. We model the headrest connection mechanism as a virtual link using kinematic modeling and perform trajectory analysis. Using the trajectory of motion, we select an oblong shape for the guide slot by fitting it with the equation of an ellipse and propose a new headrest connection mechanism. To evaluate the design of the proposed mechanism, we model the shape of the mechanism and test it using dynamic simulation under collision conditions. In addition, we design a prototype for the proposed guide, conduct a sled test, and confirm that the neck force is reduced by the proposed connection structure. In the proposed structure, the values of maximum upper neck shear and tension decreased by more than 20 % compared to existing headrest.

Key Words

Headrest Neck injury Neck force Guide slot Rear end collisions 


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Copyright information

© The Korean Society of Automotive Engineers and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringKongju National UniversityChungnamKorea
  2. 2.Industrial Technology Research InstituteKongju National UniversityChungnamKorea
  3. 3.Department of Mechanical Engineering (Industrial Technology Research Institute)Kongju National UniversityChungnamKorea

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