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The 17. world congress in traffic medicine Abstract of: Title: Whiplash-Injuries - A theoretical model to study affections of the body in rear-end collisions and similar incidents. Author: Pettersen Kjell Olav. Naval Architect. Address of author: Vollen, N-5381 Glesvaer, Norway
The mechanism may involve all parts of the body, from the lower part of the spine to the head. By strains and deflections of the spine, damage to the medulla as well as central areas of the brain might occur. Dependent of how the person is seated and the properties of the structures, as the seat, the acceleration of the person may be considerable even in low velocity collisions. The purpose of this study was to design a theoretical model describing the effects of different factors occurring in rear-end collisions. The method is based on the principals of impact mechanics. In the calculations the deformation values of car models, seat structures, weights and velocities as well as weight and position of persons have been incorporated. The car models have mathematical defined zones in front and rear, giving exact force-displacement values. By varying these factors, the model gives the possibility to show relations between the events and the forces affecting the different parts of the body. It takes into consideration a variety of conditions that might occur during the different phases of a collision. It describes how loads affect the spine and head of the persons involved. Furthermore the load patterns and the movements of the body are dependent of the initial position. Calculations show that the affecting forces might be considerable even in low velocity collisions thus creating chains of loads running within and between body elements well described by the similarity of a whip. The acceleration of the body in a collision must be considered as an impact between the car and the body as the body is delayed. To make such an evaluation, a thorough examination of each case has to be done, not only of the structural strength of cars and how they were struck, but also the flexibility of seat structures and the way the person was seated. In conclusion it seems difficult without taken into account the variety of forces acting on the body to proclaim the lower limit of collision strength leading to possible damages. |
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Glesv? Teknikk og Media, ing. Kjell O. Pettersen,
5381 Glesv?. Tlf.: 56 31 78 48 E-post: post@glestek.no |