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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.

A series of eight sled tests was conducted using Hybrid III dummies and cadavers in order to examine the influence of foot placement on the brake pedal in frontal collisions. The brake pedal in the sled runs was fixed in a fully depressed position and the occupants' muscles were not tensed. The cadaver limbs and the Hybrid III lower extremities with 45° ankle and soft joint-stop were extensively instrumented to determine response during the crash event. Brake pedal reaction forces were measured using a six-axis load cell and high speed film was used for kinematic analysis of the crashes. Four right foot positions were identified from previous simulation studies as those orientations most likely to induce injury. In each test, the left foot was positioned on a simulated footrest, acting as a control variable that produced repeatable results in all dummy tests. Each of the different right foot orientations resulted in different loads and motions of the right leg and foot.

Originally designed for measuring closed-loop contours such as those around a human thorax, the External Peripheral Instrument for Deformation Measurement (EPIDM), or chestband, was developed to improve the measurement of dummy and cadaver thoracic response during impact. In the closed-loop configuration, the chestband wraps around on itself forming a closed contour. This study investigates the use of the chestband for dynamic deformation measurements in an open-loop configuration. In the open-loop configuration, the chestband does not generally form a closed contour. This work includes enhanced procedures and algorithms for the calculation of chestband deformation contours including the determination of static and dynamic chestband contours under several boundary conditions.