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Barrier crash simulations with a torsobelted Part 572 dummy were conducted to determine the influence of knee bolster crush orientations of 0°–60° on lower extremity restraint. Responses from two sled velocity and mean deceleration severities were investigated: 6.6 m/s at 7.5 g and 13.5 m/s at 13.9 g. The dummy’s knees were prepositioned 10 cm from individual experimental bolsters, which crushed along a predetermined axis. Bolster orientation had only a minor effect on the level of peak dummy femur, and resultant knee bolster reaction load and on lower extremity kinematics of the torsobelted occupant; however, the local loading of the knee and level of tibial compression were significantly influenced.

Conceptually, a steering wheel mounted air cushion is inflated before the upper torso of the driver significantly interacts with the cushion. However, this might not be the case for some seating postures or vehicle crash environments which could cause the driver to significantly interact with an inflating cushion. These experiments utilized several environments to study the interaction between an inflating driver air cushion and mechanical surrogates. In these laboratory environments, the measured responses of mechanical surrogates increased with diminishing distance between the surrogate's sternum and the steering wheel mounted air cushion.

Previous pendulum impact tests have shown that knee joint injuries and tibial-fibular fractures may occur when loads are directed against the lower leg rather than directly against the femur in the knee. In order to further improve our understanding of lower extremity restraint mechanics, simulated frontal barrier crash experiments were conducted with unembalmed human cadavers and an anthropomorphic dummy restrained by a two-point shoulder belt. In the first test, an experimental bolster was specifically positioned so that the cadaver's lower leg would strike the bolster, thus inducing restraining loads entirely below the knee joint. The analysis of occupant kinematics showed that the flexed knee rode over and forward of the low-positioned bolster. Restraint induced considerable shearing load across the knee joint. Bolster measurements indicated a peak load of approximately 4.0 kN per leg which resulted in a contralateral central tear of the posterior cruciate ligaments.

This study identifies important parameters that influence the basic response mechanics of a compressible column steering assembly. Energy can be absorbed either by column compression and/or steering wheel deformation, depending on relative deformation force. Neither column compressive force nor steering wheel deformation force are uniquely defined but depend on several parameters. Steering wheel deformation force is dependent on occupant load distribution. The force necessary to compress the column differs from the column EA element compressive force due to inertial and geometric considerations. For our test conditions and the components we studied, off axis impact resulted in initial steering wheel deformation with the wheel and column sharing energy absorption. Axial impact resulted in almost negligible wheel deformation and the column was the energy absorbing component.

Post-crash conditions of a car's steering system, when properly measured and documented, provide an insight to the interaction between the driver and the steering system that occurs during a frontal car crash. Steering system conditions were investigated in two interrelated phases: 1. Deformation of the wheel rim, spokes, and hub, and 2. Compression resistance force of the steering column. Two devices were developed to document the “crash loading” response of these two segments of the car's steering system. One device was designed to measure the deformations of the steering wheel and the other the force required to further compress the steering column. An initial test series on 19 “crashed” cars “field tested” the devices, developed the test techniques and procedures needed for in-depth studies, and formulated necessary data handling methods and data collection forms.

The purpose of this study was to replace the axial deforming elements in the current EUROSID dummy with spring steel ribs and attached damping material to provide improved biofidelity in the lateral chest impact response. This report provides a description of the design, construction, and evaluation of the modified EUROSID chest for injury assessment in side impact crashes. Three spring steel ribs were designed to provide stiffness and deflections of 120 mm when attached to the block on the spine of the EUROSID dummy. Damping material was epoxied to the ribs and the system provided biofidelity in the lateral impact response for blunt impact loading at 4.3 m/s and 6.7 m/s. The new design provides significantly reduced inertia of the near side rib cage, elastic and viscous properties that are representative of the lateral human response and the ability to measure the deflection response of the rib cage for injury assessment with the Viscous response.