Evaluation of the kinematics and injury potential to different sizes of pedestrians impacted by a utility vehicle with a frontal guard

Abstract

A review of accident data reveals that in most pedestrian accidents, the head and lower extremity injuries are the predominant areas of injury to the pedestrian. The vehicle front geometry profile and stiffness, as well as impact speed are important factors governing pedestrian kinematics. Accident data show that the fatality rate for pedestrian/utility vehicle impact is greater than that for pedestrian/passenger car impact. The addition of a front guard on light trucks and sports utility vehicles to mitigate damage during off-road activity, or to provide mounting points for extra lights, makes the pedestrian more vulnerable to the impact. In this study, a computational technique is utilised to quantify the influence of the added front guard on the impacted pedestrian. A computer-aided design model of a typical commercial frontal guard is developed, and the finite element analysis, along with impact test, is conducted to obtain the stiffness properties of the guard. Different sizes of pedestrian models in the MADYMO code are utilised, and the validated facet-surface model of a pickup truck is used to generate a vehicle front surface. The entire model is validated by comparing the pedestrian kinematics and injury parameters with the published data. This study demonstrates that for all sizes of pedestrians, the mid-body region is more vulnerable when a guard is added to the vehicle. The results from this study can be utilised in the designing of front guards, the frontal crash zone of utility vehicles and installation of these aftermarket guards in order to protect vulnerable road users.