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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.

Experimental testing was performed to provide input data for a new, multi-body computer model of the Hybrid III lower extremity, with the 30 degree dorsiflexion ankle. The leg was disassembled into its components to mass, geometric, and inertial properties for each segment. Stiffness and damping coefficients were measured for the hip, leg, foot, and ankle. Joint rotational and translational properties were measured for the knee and ankle. To characterize interactions of the foot with the footwell, flexion and compression tests of the foot were conducted. The lower extremity was segmented at the joint and load cell locations, to permit rigid body dynamics codes to compute the forces at these locations for comparison to test data and for calculation of injury criteria.

Traumatic aortic rupture is a significant cause of fatalities in frontal automobile crashes. However, such ruptures are difficult to reproduce experimentally in cadaveric surrogates, and it is difficult to observe dynamic aortic response in situ. So, the aortic injury mechanism or mechanisms remains in dispute. This study is a staged investigation of the physical parameters and mechanisms of human aortic rupture. The investigation includes both experimental study of local and global viscoelastic properties and failure properties of aortas using aortic tissue samples, excised aortas in vitro, and whole human aortas in situ in cadaver thoraxes. This study is the first phase in a staged programme to develop a finite element computer model of aorta injury to examine the mechanisms of aorta injury in automobile crashes.