Pedestrian injury severity in the event of a collision with a truck: are energy absorbing adaptive deformable fronts suitable?

It is well known that adaptive deformable fronts attached to trucks reduce pedestrian injury. However, the suitability of these frontal attachment devices from a holistic point of view, considering both primary and secondary impacts, is questioned in this paper. Using head-injury-criteria index, the effects of pedestrian gait and different closing speeds are considered for evaluation of numerous truck-pedestrian side and rear impact situations. Numerical simulations, considering coupled rigid and deformable-body dynamics, have been carried out in this paper to arrive at conclusions. For primary side impact scenario DEA frontal attachment provides a performance improvement specifically for 0% gait; however, the performance improvement is non-uniform for other gait cycles. For primary rear impact scenarios, it is observed that DEA is not a useful alternative at all. For secondary collision scenarios (involving both side and rear impacts) DEA is not at all an effective means for performance improvement.