Modelling the effects of an inflatable tubular structure (ITS) on occupant kinematics and injury risk in the rollover of a sports utility vehicle (SUV)

The aims of this study are to investigate the responses of a Hybrid III dummy and a human body model in rollover crashes of an SUV, and to assess the effect of an inflatable tubular structure (ITS) on the unrestrained occupant kinematics in rollover events. A SAEJ2114 rollover test of a 1994 Ford Explorer with an inflatable tubular structure (ITS) is simulated for two front row occupants, and validated in MADYMO. By removing the ITS, the simulation of the Hybrid III dummy occupants without ITS is obtained. By replacing the dummy models with human body models, with and without ITS, two other simulations are also modelled. The kinematics and injury risks of the two occupant models are compared and evaluated. Significant differences exist in the motions, and injury levels of the dummies and human body models with and without ITS. ITS can offer significant protection to the head by cushioning the impact of the head on the roof or side windows, and can mitigate against occupant ejection. The flexibility of the spine and the neck of the human body models significantly affects the kinematics and the severity of the injuries of the occupants modelled, and so would also affect the relevance of the design of countermeasures developed from dummy tests to real-world rollover crashes of human beings.