In the United States, air bags are required in all passenger cars and light trucks. The National Highway Traffic Safety Administration (NHTSA) has estimated that almost 2,800 lives have been saved by the air bags. However, air bags designed to protect passengers have, in some situations, caused serious injuries, especially in moderate impacts. Last year, in order to reduce injuries caused by air bag inflation, NHTSA revised the requirements for FMVSS 208 unbelted testing to allow the sled test protocol as a temporary alternative to the frontal barrier vehicle crash test. It is believed that this decision will allow manufacturers to depower air bags by about 20-35 percent, decreasing aggressiveness of air bags during inflation. The NHTSA continues to use the New Car Assessment Program (NCAP) 35mph frontal barrier test as a "measure" of vehicle crashworthiness. The NCAP test report data are widely disseminated to the public as vehicle safety information. This paper evaluates the effects of air bag depowering on dummy measurements under both moderate frontal impact and severe 35mph frontal barrier impact using MADYMO simulations. These simulations suggest that the aggressiveness of the air bag deployment can be greatly reduced in moderate impacts, without compromising occupant protection performance in more severe impacts. (A)
Abstract