Finite Element Modeling and Simulation of Inflatable Tubular Structure Airbag

Abstract

Abstract The Inflatable Tubular Structure (ITS) airbag is a potentially life-saving device that has been implemented recently in some luxury passenger vehicles. When deployed, the ITS-airbag provides primarily protection of the front seat occupant’s head and face against upper side-interior car components. In the current research, a nonlinear Finite Element (FE) model for ITS-airbag system was proposed, developed, and tested in a side impact using dummy-head and neck FE model. The modeling technique of the unique behavior of the outer layer of the ITS-airbag is explained in details. Modeling such a complicated behavior of the ITS (axial shrinkage and radial expansion) was successfully performed by using a combination of diagonal truss elements combined with an isotropic fabric material. Nonlinear FE side-impact simulations for a Hybrid-III dummy-head and neck model impacting a vehicle’s side glassing, roof-rail, and B-pillar using the ITS airbag system were conducted using the explicit FE code LS-DYNA. The developed ITS model has reduced the Head Injury Criteria (HIC) and the peak-acceleration of the dummy-head significantly. The results indicated the ability of the developed finite element model to represent the real ITS airbag system and therefore provide a reliable nonlinear FE simulation results that could be used to test, improve, and validate the implementation of the ITS airbag systems in more vehicles.