The purpose of this study is to investigate the contribution of a seat suspension in absorbing a part of the impact energy. Standard test conditions were considered for frontal direction of crash impacts.

A first research project has lead to the development of an active seat suspension according to ride comfort motivations, let to isolate the occupant from vertical vibrations. This study has been performed to demonstrate the capability of an active isolation device to optimize seat car vibratory isolation (Périsse, 1997). In this paper, a passive damper seat suspension is studied.

A multibody approach was chosen to model the seat and the occupant because of its reliability to resolve crash computational problems with hightly nonlinear mechanical elements. A particular attention was paid to the influence of seat belt positions, the stiffness and damping characteristics of the suspension.

The simulation results demonstrate the seat suspension capability to answer to crash injuries criteria and, in some cases, its usefullness to reduce the head acceleration levels. Finally, it was shown that a seat suspension can be considered as a crash absorbing device.