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The University of Virginia is investigating the use of a magnetohydrodynamic (MHD) angular rate sensor to measure head angular acceleration in impact testing. Output from the sensor, which measures angular velocity, must be differentiated to produce angular acceleration. As a precursor to their use in actual testing, a torsional pendulum was developed to analyze an MHD sensor's effectiveness in operating under impact conditions. Differentiated and digitally filtered sensor data provided a good match with the vibratory response of the pendulum for various magnitudes of angular acceleration. Subsequent head drop tests verified that MHD sensors are suitable for measuring head angular acceleration in impact testing.

This paper describes the development of an automated Door Test Facility for implementing the Door Component Test Methodology for side impact analysis. The automated targeting and loading of the door inner/trim panels with Side Impact Dummy (SID) ribcage, pelvis, and leg rams will greatly improve its test-to-test repeatability and expedite door/trim/armrest development/evaluation for verification with the dynamic side impact test of FMVSS 214 (Occupant Side Impact Protection). This test facility, which is capable of evaluating up to four (4) doors per day, provides a quick evaluation of door systems. The results generated from this test methodology provide accurate input data necessary for a MADYMO Side Impact Simulation Model. The test procedure and simulation results will be discussed.

This report describes an experimental validation of an ellipsoid-to-foam contact model. A series of static foam tests was conducted using Side Impact Dummy rib cage, pelvis, upper leg, and wooden ellipsoids as impactors to validate a theoretical foam contact model previously developed. Predicted results of contact forces, calculated using the uni-axial stress-strain relationship and contact areas, yield good correlation with the test data. These studies used CFC foams and were conducted prior to switching to water-blown foam material development. The ellipsoid-to-foam contact model is being integrated into a MADYMO side impact model. The MADYMO/foam simulation model can then be used to help evaluate design variable tradeoffs (e.g., door thickness vs. body side structures and foam padding requirement vs. interior package) thereby reducing the current dependency on testing, bolster development time, and cost.

This paper describes further developments of the MVMA-2D model including program modifications of the air bag and the energy absorbing steering assembly submodels. The air bag submodel and the steering assembly submodel in the MVMA-2D crash victim simulation are independently formulated. No coupling exists between these two submodels to permit simulation of the kinematics of an anthropomorphic dummy restrained by a driver air bag restraint system mounted on a collapsible steering column. The development effort of integrating both submodels to provide the MVMA-2D model with such a capability is presented. The integrated model has been successfully utilized in simulating dynamic responses, in frontal impact situations, of a dummy restrained by a driver air bag restraint system mounted on a collapsible steering column. Validations of the model were made by comparing simulation results with experimental test data.