Benefits of a 3+2 Point Belt System and an Inboard Torso Side Support in Frontal, Far-Side and Rollover Crashes
Technical Paper
2003-06-0175
Sector:
Language:
English
Abstract
3-point-belted occupants are still being injured in numerous
crashes. In frontal collisions this is partly explained by the
range of hard tissue tolerance amongst car occupants. In side
collisions occupants on the far side of the intrusion are mainly
restrained by the lap part of the 3-point belt, with an associated
high risk of sustaining a severe head injury. During a rollover
crash the 3-point belt cannot fully prevent harmful head
impacts.
In this study an additional 2-point belt (single-handed optional
operation) is combined with an inboard torso side support. The idea
is simply to distribute the belt load on more anatomical structures
(bones) as well as constituting a noninjurious inboard and upward
restraint. The inboard side support prevents a direct loading by
the 2-point belt to the cervical spine in far-side collisions. It
also supports the torso when the 2-point belt is not buckled.
To prove if this design measure is advantageous, frontal, far
side and rollover tests were performed. Current standard crash test
dummies lack appropriate biofidelity when assessing sophisticated
enhancements of standard safety restraints. Therefore the Thor
dummy with a set of modifications from the BioSID was used in the
tests.
The results showed a considerable reduction of chest deflection
in the frontal crash tests, head horizontal motion in the far side
tests and head upward motion in the rollover tests. To conclude, an
additional 2-point belt, in conjunction with, a 3-point belt and
inboard torso side support offer a considerably increased
protection in various crash situations without any negative
consequences.