Car Crash Theory and Tests of Airbag Bumper Systems

A frontal barrier crash at 48.5 km/h and a moving rigid barrier crash at 48.5 km/h into the side of a stationary car have been carried out at the Insurance Institute for Highway Safety's Vehicle Research Center, with the car having frontal then side preinflated airbag bumpers. This is a preliminary simulation of an airbag bumper system with the needed airbag inflation triggered by radar sensing of the approaching threat. The frontal airbag bumper had a high pressure airbag at 221 kPa and 23 cm thick imbedded on the outboard side of a low pressure airbag at 20 kPa whose inboard side was against the original car bumper, with a thickness of an additional 61 cm at the center line, for a combined thickness of this prototype airbag bumper of 84 cm. The low pressure airbag ruptured as expected in the frontal crash, with the airbag bumper absorbing about 19 percent of the energy of the crash due to excessive penetration into frontal structures. In the side crash, the high pressure airbag at 76 kPa and 20 cm thick was used alone, also with excessive penetration into yielding side structures. The implications for needed airbag bumper design and vehicle airbag bumper support structures, and inter-vehicle compatibility, are noted.