Accident statistics show that injuries to the lower extremities
are quite frequent in accidents. In most cases these injuries are
not life-threatening, but the related treatment & convalescence
costs are quite high. In this study different factors influencing
lower extremity injuries were investigated. To define the relevant
parameters, a baseline crash test under Euro NCAP conditions with
instrumented hybrid III legs was performed. Using these test
results, a simulation model and a sled test model were set up in
parallel and validated with respect to the baseline crash test. The
main areas for improvement to the lower extremities were defined
and from these, six different protection concepts were
investigated: 1.) Foot airbag, 2.) Foam padding (toeboard), 3.)
Active unlocking of brake pedal, 4.) Reduction of translational
toeboard intrusion, 5.) Reduction of rotational toeboard intrusion,
and 6.) Pop- up kneebolster.
In order to investigate different combinations of these six
protection concepts, a Design of Experiments (DoE) matrix was
created and 108 simulation runs were performed. Based on the
simulation results, six different combinations of these protection
concepts were tested on the sled. Finally, the performance of the
best protection system combination was verified in a full-scale
crash test.