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A simulation model of the Hybrid III lower extremities with the 30 degree dorsiflexion ankle was developed using the CVS/ATB program. The femur and tibia were modeled as a sequence of rigid beams with a hinge and slider at the knee. Special, locked joints were placed in the femur and tibia at the same locations as the load cells in the actual dummy. Constraint forces and moments at these joints can be compared directly to load cell data. The complex geometry of the foot was divided into five segments representing the heel, toe, forefoot, midfoot, and ankle regions. Two foot models were constructed: one barefoot and one with a Lehigh safety shoe. Good agreement was obtained for most parameters when single-leg pendulum tests, and full-body sled tests, were simulated using the new model.

The air bag has proven effective in reducing fatalities in frontal crashes with estimated decreases ranging from 11% to 30% depending on the size of the vehicle [IIHS-1995, Kahane-1996]. At the same time, some air bag designs have caused fatalities when front-seat passengers have been in close proximity to the deploying air bag [Kleinberger-1997]. The objective of this study was to develop an accurate and repeatable out-of-position test fixture to study the deployment of air bags into out-of-position occupants. Tests were performed with a 5th percentile female Hybrid III dummy and studied air bag loading on the thorax using draft ISO-2 out-of-position (OOP) occupant positioning. Two different interpretations of the ISO-2 positioning were used in this study. The first, termed Nominal ISO-2, placed the chin on the steering wheel with the spine parallel to the steering wheel.

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.

Three-dimensional simulation models of a driver's right upper extremity interacting with a deploying airbag have been set up and run with the Articulated Total Body program. The goal of this study is to examine the significance of various occupant and airbag parameters during deployment, such as grip strength, upper extremity position, shoulder compliance, flap position, flap aggressivity, and deployment speed. Given a range of 250 N to 650 N, the grip strength did not affect the resultant loads. Also, the contact force and torque at the e.g. of the forearm are not sensitive to shoulder joint compliance. The flap aggressivity and the position of the airbag module relative to the upper extremity are most important in affecting the interaction. This study is used to justify cadaveric experiments involving disarticulated upper extremities.

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.

This paper presents dummy and cadaver experiments designed to investigate the injury potential of an out-of-position small female head and neck from a deploying side air bag. Three seat mounted, thoracic type, side air bags were used that varied in inflator aggressivity. The ATB/CVS multi body program was used to identify the worst case loading position for the small female head and neck. Once the initial position was identified, a total of three Hybrid III 5th percentile dummy and three small female cadaver tests (51 ± 9 years, 64 ± 8 kg, 159 ± 10 cm) were performed. Instrumentation for the dummy included upper and lower neck load cells, while both the dummy and the cadavers had accelerometers and angular rate sensors fixed to the head and T1 vertebrae in order to provide head and neck kinematic data. Head center of gravity accelerations for the dummy ranged from 71 g's to 154 g's, and were greater than cadaver values, which ranged from 68 g's to 103 g's.