Investigating Pedestrian Kinematics with the Polar-II Finite Element Model

This paper is from the SAE World Congress & Exhibition, held in April 2007 in Detroit, Michigan, USA. Part of the Pedestrian Safety session, this paper reports on a study of pedestrian kinematics with the Polar-II Finite Element Model. The authors describe how earlier studies on pedestrian-vehicle impact kinematics used post-mortem human surrogates (PMHS) and determined that vehicle shape may influence pedestrian kinematics and injury mechanisms. The authors describe finite element (FE) modeling as a more feasible approach, since numerous experiments can be conducted with a significantly lower cost. The authors report on their study which used an FE model of the Polar-II pedestrian dummy to evaluate the influence of shifting body contact points with respect to vehicle geometry on impact kinematics. Multiple simulations were performed by moving the pedestrian vertically with respect to the vehicle reference frame. Another component of the study was undertaken to evaluate the contribution of the mass distribution with respect to vehicle geometry. In this part, simulations were performed where the center of gravity of the dummy was shifted around the baseline location. The authors discuss the results of this study which suggest a nonlinear sensitivity of response to changes in the body contact points with respect to vehicle structures, as well as a linear variation of upper body trajectories when the dummy center of gravity height was adjusted.