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This paper presents a parametric study that utilized the CVS/ATB multi-body simulation program to investigate the interaction of the hand and wrist with a door handgrip during side air bag loading. The goal was to quantify the relative severity of various hand and handgrip positions as a guide in the selection of a test matrix for laboratory testing. The air bag was represented as a multi-body system of ellipsoidal surfaces that were created to simulate a prototype seat-mounted thorax side air bag. All simulations were set in a similar static test environment as used in corresponding dummy and cadaver side air bag testing. The occupant mass and geometric properties were based on a 5th percentile female occupant in order to represent a high-risk segment of the adult population. The upper extremity model consisted of wrist and forearm rotations that were based on human volunteer data.

Axial loading of the foot/ankle complex is an important injury mechanism in vehicular trauma that is responsible for severe injuries such as calcaneal and tibia pilon fractures. Axial loading may be applied to the leg externally, by the toepan and/or pedals, as well as internally, by active muscle tension applied through the Achilles tendon during pre-impact bracing. In order to evaluate the effect of active muscle tension on the injury tolerance of the foot/ankle complex, blunt axial impact tests were performed on 44 isolated lower legs with and without experimentally simulated Achilles tension. The primary fracture mode was calcaneal fracture in both groups, but tibia pilon fractures occurred more frequently with the addition of Achilles tension. Acoustic emission demonstrated that fracture initiated at the time of peak local axial force.

Real-world crash investigations have suggested that lower limb injury risk is increased with the occurrence of toepan intrusion in a frontal collision. In order to more closely evaluate the effects of different modes of toepan intrusion, a rotational and translational intrusion device was built for the test sled at the University of Virginia. Sled tests were performed at a velocity of 56 km/h with a belted Hybrid III occupant and a simulated knee bolster and steering wheel air bag. Lower limb injury risk measures were obtained with Hybrid III and Thor Lx dummy lower extremities. Dummy response variables of interest included tibia axial and shear loads, tibia bending moments, ankle rotations and foot and tibia accelerations. The tests were conducted with no intrusion and with a translational intrusion with a peak deceleration of approximately 175 g's with 14 cm of translation.