Aspects of Simulation of Automobile Seating Using LS-Dyna 3D

P. Williamson (P+Z) The simulation of automotive seating continues to reduce prototype turnaround times and the cost involved with unnecessary prototype testing. With the increasing complexity of seat design, driven mainly by OEM requirements and consumer wishes, modeling techniques and methods are also being challenged to improve the ability to make quick and accurate judgements on the kinematic behavior and stability of the seat structure. Complex systems such as rails, latches, retractors, seat foam, removable-seats-systems or belt pretensioners rely on complex loading and unloading functions and or robust contact formulations to ensure stability during the simulation. This paper will investigate a problem for which, during testing and simulation, notable interaction was seen between the seatbelt and the upper backrest of seat structure. In order to analyse this interaction a 2-D model of the shoulder belt complete with shell elements and a simple D-Ring model was constructed. This approach along with an alternative configuration will be touched upon. This paper also aims to show some of the options LS-Dyna uses to keep the simulation of the seat structure, including loading devices, stable for which extreme loading and large deformation will be prevalent. The elements and models used i.e. dummy, seat and restraint system will be outlined. A short description of the pre- and post- processors used has been included. Methods used and developed by P+Z Engineering used in seat positioning will also be shown.