ASPECTS OF SEAT BELT MATERIAL SIMULATION

The so-called D-ring dynamic overturning is an instability phenomenon occurring occasionally during car crashes. It can have a negative effect to the restraint function of the seat belt system and lead to increased seat belt forces to the occupant. In order to avoid this phenomenon the influence of different parameters has to be investigated. Therefore a simulation model has been created, using the Finite Element Code LS-DYNA 3D. Major questions to be clarified in this context are: • Define initial geometry for the belt running through the D-ring. • Choice of appropriate material model. • Influence of physical parameters, i.e. D-ring geometry, friction properties, belt material, belt forces, crash pulse, etc. The definition of the initial geometry and a feasibility study have been presented at the 2000 CAD-FEM conference [2]. The modelling method, results for a given baseline geometry, variations in different material models and the pre-simulation of a new concept of the D-ring, the so called “roller D-ring” are presented in the current paper.