LOWER LEG INJURY IN RELATION TO VEHICLE FRONT-END

An analytical model has been introduced to predict tibial acceleration, knee shear displacement, and knee lateral bending, given the bumper and spoiler characteristics as input. Results The parametric analysis has demonstrated that bumper stiffness, bumper profile height and spoiler stiffness do have an impact on knee lateral bending, knee shear displacement, and peak tibial acceleration. Increasing bumper stiffness can result in higher knee bending, knee shear displacement and peak tibial acceleration. Increasing bumper profile height produces lower knee bending and shear displacement. Increasing spoiler stiffness can determine higher knee shear displacement and peak tibial acceleration, but lower knee bending. Spoiler stiffness and position have a strong correlation: higher bumper stiffness needs to be coupled to a moved forward spoiler position. The mechanical responses of the spoiler and of the bumper can be assumed to be linear: the softening behaviour of the EPP foam balances the hardening behaviour of the fascia (due to contact area increase). The predictive model is well correlated to experimental findings (R2>0.74) Conclusions This simplified computer model can be used as a pre-screening design tool to demonstrate general vehicle front-end design trade-offs and provide approximate results without physical testing