Structural crash analysis with ADAMS: a comparison between multibody and FEM approaches

The work deals with modelling of mechanical structures subjected to impact loading by multi-body approach. Main goal is to demonstrate the capability of this type of approach to describe the large plastic collapse of structural members when they are involved in the crash event in case of vehicle impact. In order to match this scope new basic elements to be added in the multi-body code library have been developed able to describe the axial and the bending plastic behaviour of collapsing members. The paper describes the specific features of these new elements and proposes some applications to the analysis of crash case for typical automotive structures. The obtained solutions are also compared with solutions obtained by finite element analysis using the DYNA3D code. It can be concluded that the multi-body approach allows to obtain solutions in shorter calculation time and with reasonable approximation, resulting therefore a powerful approach for the analysis especially in the first structural layout design.