ADVANCED BENEFIT ANALYSIS OF THE ITS-AIRBAG IN VEHICLES' SIDE- IMPCTS — FE SIMULATION AND SEVERITY ANALYSIS

Document Type : Original Article

Authors

1 Research Scientist, FHWA/NHTSA National Crash Analysis Center, GW Transportation Research Institute, The George Washington University, Ashburn, VA, USA.

2 Professor and Co-Director, GW Transportation Research Institute, The George Washington University, Ashburn, VA, USA.

Abstract

The Inflatable Tubular Structure (ITS) airbag is a potentially life-saving device that has been implemented recently in some luxury vehicles. Its main objective is to provide head protection for the front seat occupants against upper side-interior car components. In a previous research conducted by the authors, a nonlinear Finite Element (FE) model for the ITS-airbag system was successfully developed and tested. In the current research, the developed ITS model is combined with a full-scale FE vehicle model and 50th percentile side-impact dummy (SID) model. The combined model is then used to conduct two series of side-impact simulations. The first series included side impacts with narrow objects, i.e. rigid poles, while the second series included side impacts with a Moving Deformable Barrier (MDB) as a wide and deformable object. The effect of the relative position between the dummy and the rigid pole was considered by conducting variety of simulation scenarios for two different rigid pole positions and three different dummy positions. The three dummy positions were also considered in the side impacts with the MDB. For both impact series, the effect of the impact velocity was considered by conducting each impact scenario at three different velocities. The ITS model performance, in all
FE simulations, was fairly similar to the actual ITS performance. The simulation results indicated a significant reduction in the Head Injury Criteria (HIC) of the dummy head due to the ITS-airbag deployment. The life-threatening severity for occupants is usually measured by the Abbreviated Injury Scale (AIS) that ranges from 1 (minor) to 6 (fatal). The AIS indices are calculated for all side impact cases. The results demonstrated a significant reduction/elimination in side-impact fatalities and severe injuries due to the ITS-airbag performance. The FE simulation results are then used in conducting a comprehensive benefit analysis for the ITS- airbag systems in vehicles' side-impacts.

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