A study on the influence of the seat and head restraint foam stiffnesses on neck injury in low speed offset rear impacts

Author(s):  
Hui-Chang Jo ◽  
Young-Eun Kim
Author(s):  
J Latchford ◽  
E C Chirwa ◽  
T Chen ◽  
M Mao

Car-rear-impact-induced cervical spine injuries present a serious burden on society and, in response, seats offering enhanced protection have been introduced. Seats are evaluated for neck protection performance but only at one specific backrest angle, whereas in the real world this varies greatly owing to the variation in occupant physique. Changing the backrest angle modifies the seat geometry and thereby the nature of its interaction with the occupant. Low-velocity rear-impact tests on a BioRID II anthropomorphic test dummy (ATD) have shown that changes in backrest angle have a significant proportionate effect on dummy kinematics. A close correlation was found between changes in backrest angle and the responses of neck injury predictors such as lower neck loading and lower neck shear but not for the neck injury criterion NICmax. Torso ramping was evident, however, with negligible effect in low-velocity impacts. The backrest angle ranged from 20° to 30° whereas the BioRID II spine was adapted to a range from 20° to 26.5°. Nevertheless, in general, instrumentation outputs correlated well, indicating that this ATD could be used for evaluating seats over a 20–30° range rather than solely at 25° as required by current approval test specifications.


2000 ◽  
Vol 32 (2) ◽  
pp. 243-250 ◽  
Author(s):  
Yoichi Watanabe ◽  
Hideaki Ichikawa ◽  
Osamu Kayama ◽  
Koshiro Ono ◽  
Koji Kaneoka ◽  
...  
Keyword(s):  

Spine ◽  
2004 ◽  
Vol 29 (21) ◽  
pp. 2404-2409 ◽  
Author(s):  
Annette Kettler ◽  
Kai Fruth ◽  
Erich Hartwig ◽  
Lutz Claes ◽  
Hans-Joachim Wilke
Keyword(s):  

Author(s):  
Anna Carlsson ◽  
Johan Davidsson ◽  
Astrid Linder ◽  
Mats Y. Svensson

The objective of this study was to present the design of a prototype rear impact crash test dummy, representing a 50th percentile female, and compare its performance to volunteer response data. The intention was to develop a first crude prototype as a first step toward a future biofidelic 50th percentile female rear impact dummy. The current rear impact crash test dummy, BioRID II, represents a 50th percentile male, which may limit the assessment and development of whiplash protection systems with regard to female occupants. Introduction of this new dummy size will facilitate evaluation of seat and head restraint (HR) responses in both the average sized female and male in rear impacts. A 50th percentile female rear impact prototype dummy, the BioRID P50F, was developed from modified body segments originating from the BioRID II. The mass and rough dimensions of the BioRID P50F is representative of a 50th percentile female. The prototype dummy was evaluated against low severity rear impact sled tests comprising six female volunteers closely resembling a 50th percentile female with regard to stature and mass. The head/neck response of the BioRID P50F prototype resembled the female volunteer response corridors. The stiffness of the thoracic and lumbar spinal joints remained the same as the average sized male BioRID II, and therefore likely stiffer than joints of an average female. Consequently, the peak rearward angular displacement of the head and T1, and the rearward displacement of the T1, were lesser for the BioRID P50F in comparison to the female volunteers. The biofidelity of the BioRID P50F prototype thus has some limitations. Based on a seat response comparison between the BioRID P50F and the BioRID II, it can be concluded that the male BioRID II is an insufficient representation of the average female in the assessment of the dynamic seat response and effectiveness of whiplash protection systems.


Author(s):  
Jae-Won Lee ◽  
Ji-Hae Kim ◽  
Tae-Won Kim

The most frequent type of traffic accident is a low-speed rear-end collision, which can damage parts of the vehicle, including the bumper, and cause neck injury to the occupants. Even in minor damage accidents, such as scratches on bumper covers, 26.3% of occupants received treatment for bodily injuries whose main symptom was neck injuries through auto insurance. This study was conducted to evaluate the potential for neck injuries in low-speed accidents. Fifty-nine low-speed rear-end impact tests were conducted, and the motion of the struck vehicle and the neck injury criterion (NIC) of the occupant according to the test conditions were predicted using multiple linear regression derived via supervised machine learning. It was confirmed that the NIC can be predicted using vehicle motion values that can be obtained through an event data recorder. The coefficients of determination of the regression equations were 0.67–0.83. Lastly, we investigated whether neck injuries can be predicted through bumper cover damage that can be checked immediately after a vehicle accident. In the case of the vehicle damage type 1/2/3 category applied to auto insurance by the Korean government, an occupant would have a very low possibility of neck injury or symptoms. No symptoms or injuries were reported in the volunteer tests conducted for this study.


2005 ◽  
Vol 38 (8) ◽  
pp. 1694-1701 ◽  
Author(s):  
Manohar M. Panjabi ◽  
Shigeki Ito ◽  
Paul C. Ivancic ◽  
Wolfgang Rubin
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document