Effectiveness of Wearable Protection Equipment for Seated Pedestrians

This study used finite element models to investigate the efficacy of seated pedestrian protection equipment in vehicle impacts. The selected safety equipment, a lap belt, an airbag vest, and a bicycle helmet, were chosen to mitigate the underlying biomechanical causes of seated pedestrian injuries reported in the literature. The impact conditions were based on the three most dangerous impact scenarios from a previous seated pedestrian impact study. Serious injury (AIS 3+) risks were compared with and without protective equipment. A 50th percentile male occupant model and two generic vehicle models, the family car (FCR) and sports utility vehicle (SUV), were used to simulate vehicle collisions. Three impact conditions were run with every combination of protective equipment (n = 24). The helmet reduced head and brain injury risks from the vehicle-head and ground-head contacts. The airbag reduced the head injury risk in the FCR vehicle-head contact but increased the brain injury risks in the SUV impacts from increased whiplash. The lap belt increased head injury risks for both the FCR and the SUV impacts because it created a stronger FCR vehicle-head contact and SUV ground-head contact. When the belt and airbag were used together the head injury risks dramatically decreased because the pedestrian body impacted the ground arm or leg first and slowly rolled onto the ground which resulted in softer ground-head contacts and in two instances, no ground-head contact. Only the helmet proved effective in all impact conditions. Future testing must be completed before recommending the belt or airbag for seated pedestrians.