Modeling of Folding of Passenger Side Airbag Mesh

Airbag as a safety device fitted in automobiles is fast gaining public acceptance. Improvements in design of automobile components, often achieved by computer modeling and simulations, are becoming standards for automobile testing and design. Due to airbags acceptability for four wheeled vehicles, the concept of airbag in motorcycles is now being tested by many. Currently passenger side airbags, which have a larger volume than the driver side airbag, are considered for airbags to be mounted on motorcycles. Modeling of folding of passenger side airbag is a complex and time consuming process. In this work, the modeling of folding of passenger side airbag of 160 l is considered. This airbag mesh is to be used for exploratory simulations of crashes of an Indian motorcycle mounted with an airbag. Commercial software tools used for modeling of airbag folds do not give a realistic inflation process due to large distortion of airbag mesh elements. In this work simulations for getting the mesh of a folded passenger side airbag are used. Unreformed mesh containing six layers of cloth is first generated in Finite Element software IDEAS. This mesh is then exported to PAMCRASH. The fold sequence is then modeled using simulations so as to duplicate the manual folding process. Folds are thus generated in the airbag mesh using simulations in PAMCRASH. For each simulation of folding, the mesh is held between rigid planes and these planes are given velocities corresponding to the folding process. This method of fold simulation is time consuming. But it gives folded airbag mesh of complex shapes. Inflation process of folded airbag mesh is in better agreement with unfolded airbag mesh inflation process.