In the past few years, many cases of serious injury to out of position occupants caused by airbag deployment have been reported in the United States. FMVSS208, which requires equipping automobiles with airbags, was revised to reduce the risk of deployment injury by airbags. The new regulation defines some new test procedures and several performance requirements regarding the out of position tests. The uniform gas pressure analysis has been a general analysis method for airbag deployment with computer simulations up to this point. However the membrane force of the airbag is a major parameter for the interference between the airbag and an out of position occupant, and the gas used for airbag deployment has the characteristics of a compressible fluid which is difficult to model. Therefore the general Euler-Lagrange coupling method will be necessary for the computer simulation of out of position occupant interference. This paper describes the results of the airbag- out of position interference by using computer simulation with the general Euler-Lagrange coupling method in regards to occupant position, bag and inflator characteristics. The results of the simulation are correlated to laboratory out of position testing.
Abstract