Correlation of airbag fabric material mechanical failure characteristic for out of position applications

The current paper will discuss airbag fabric mechanical failure characterisation in order to improve simulations of airbag behaviour for out-of position (OoP) occupant scenarios. This failure mechanism is necessary to represent the controlled failure of airbag internal tethers when drivers of different mass and stature are slumped over the steering wheel, thereby contacting the airbag module at the start of the airbag deployment. The high deployment forces associated with these scenarios are caused by the increasing gas pressure inside the airbag [1]. The methodology discussed involves the execution of physical static and dynamic tensile tests of an airbag fabric sample in warp, weft and bias directions. The airbag fabric permeability is derived and airbag module cover, tear seam rupture tests are performed. Mathematical simulations of airbag fabric with nonlinear fabric material characterisations are correlated to the test results. The physical airbag fabric failure is compared to various computer simulation techniques. The correlated airbag fabric models are used in simulations with 5^th percentile female, 50^th and 95^th percentile male anthropomorphic test devices (ATD's) to demonstrate the pressure build up in the airbag chambers and provide additional knowledge of this phenomenon [2]. If a driver occupant exerts an extreme breaking intervention existing of horizontal deceleration, a 50^th percentile ATD could end up in a sort of an OoP scenario with a posture close to the driver airbag module at the moment of airbag ignition. The presented study prepares this combination of active and passive safety (integrated safety) exploring the advanced driver airbag model behaviour by varying the occupant types (size) during initial OoP deployment.