FINITE ELEMENT ANALYSIS OF LOWER LIMB INJURIES IN A PEDESTRIAN-VEHICLE COLLISION

Abstract

Half of road deaths are vulnerable road users, highlighting pedestrians. Vehicle manufacturers are essential in pedestrian protection, since vehicle design influences the crash severity. Approval tests, which evaluate the safety offered by a specific vehicle model, are destructive and involve considerable costs. This can be solved by virtual tests, as a reliable alternative to real tests, especially in repetitive trials such as the simulation of a pedestrian-vehicle collision. This research simulates different pedestrian crash scenarios by the finite element method, analysing the influence of several factors (impact speed, pedestrian position, material and height of vehicle) on injury severity in lower limbs. This area is the main cause of disability, generating high social costs, which motivates this study. Results could help to design safer vehicles and take effective measures in road safety. The analysed injury criteria, used in regulations, are: tibia acceleration, dislocation and bending angle of knee. Results show that injury severity increases exponentially with speed, as well as that in frontal crash ligaments can be seriously affected even at low speeds. Whereas in side impact, tibia has higher probability of injury. In addition, it is found that aluminium considerably improve pedestrian protection. As for height of vehicle frontal area, the smaller it is, the more affected the ligaments are. However, at higher height, greater protection is offered to tibia.