Lower Extremity and Brake Pedal Interaction in Frontal Collisions: Computer Simulation

An Articulated Total Body frontal crash simulation was created with the dummy's right foot placed on the brake pedal. This study examined how interaction of the driver's foot with the brake pedal influenced the behavior of the lower extremities in frontal collisions. Braking parameters considered in the study included foot position on the pedal, whether or not the occupant's muscles were tensed and if the brake pedal was rigid or was allowed to depress. Two basic foot positions were identified as most likely to induce injury of the lower limb. One represented a foot that was pivoted about the heel from the gas pedal to the brake pedal. The other position replicated a foot that was lifted from the gas pedal to the brake pedal, resulting in an initial gap between the heel and floor. Both positions resulted in different loads and behavior of the foot, indicating that driver pre-impact position is a contributing factor to one's injury risk. In the tests with a braced occupant, there was less motion of the foot, but the loads in the tibia were higher than the relaxed occupant due to the changes in the foot position and timing of the foot and toepan interaction. In the cases where the pedal was allowed to depress, the tibia axial load and bending moment were 10% and 13% higher than with a fixed pedal, respectively. The foot rotations and foot contact forces were not significantly different in magnitude.