The lower leg responses in frontal offset crashes were investigated using mathematical models with a complex description of intrusion. The aim of this investigation was to study injury risks caused by various toepan intrusion parameters, such as magnitude, onset time and acceleration. Toepan rotation and the shape of the deformation were also investigated as a basis for defining principles for countermeasures.
Mathematical models of a production car including the toepan and occupant were developed. As input to the modelling, feet and lower leg kinetics were filmed during a vehicle crash test. Parameters that influence lower leg responses were evaluated using a statistical experimental design. The results of the parameter studies show that both toepan acceleration and toepan rotation around the z-axis should be reduced to reduce lower leg responses. These changes should, however, be preceded by an investigation of the interaction effects among the parameters before design changes are made.