Development of a school bus restraint system model and its application in the evaluation of designed protective strategies on child neck injury in front-end crash

Abstract

In a front-end crash of a school bus, the existing child restraint system does not provide effective protection to the neck, although it can well protect other regions of the body, including the head and chest. In this study, we developed multi-body seat models with compartmentalization (no belt), lap belt and lap/shoulder belt. We verified the models against sled tests considering dummy motion trajectory and neck injury metrics. Next, we proposed two strategies to improve school bus seats, namely, equipping an energy-absorbing block to the seatback and adding a revolute joint between the seatback and the seat frame. We evaluated the performance of each improved strategy in terms of neck protection based on the validated models. The results showed that both improvements effectively reduced neck injury. This study can provide useful guidance for the design of new school bus restraint systems.