Finite element analysis of occupant head and neck injury mechanism during rollover crashes

A set of state-of-the-art Finite Element (FE) vehicle restraint system, crash dummy and whole body human models was integrated and validated against several quasi-static and dynamic rollover tests. HIII dummy responses during three selected trip-over scenarios were simulated using an FE vehicle model equipped with four different hypothetical roof stiffness values. Results indicated that both previous hypotheses on rollover injury mechanism, i.e. 'diving mechanism' and 'roof crush mechanism', are flawed. The results supported that 'diving' is the major injury mechanism in rollovers, but 'roof stiffness' (not 'roof crush') affects the head and neck injury risks for far-side occupants during 'diving' type of impacts. Traditional 'diving mechanism' neglected the fact that roof stiffness can change the vehicle and occupant kinematics in rollovers, and consequently affected the occupant injury risks. More rollover tests using both the dummy and the cadaver are needed to further validate the hypothesis proposed in this study.