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In the current highway vehicle accident environment a large percentage of fatalities and injuries occur in frontal offset crashes. Computational modeling is being used in support of crashworthiness studies at the National Highway Traffic Safety Administration (NHTSA) to develop an understanding of structural response in offset crash events. This paper presents a lumped-parameter approach to modeling offset impacts. Applications for offset models are discussed, including providing inputs to occupant simulations and as the basis of multipurpose frontal impact models. The role of discretization errors, nonuniaxial motions, and test data dependence and sensitivity in limiting model accuracy is discussed. Extensions to the modeling methodology that will better support offset events are identified.

The National Highway Traffic Safety Administration has initiated research to develop performance specifications for dummy-based accelerometers in the crash test environment, and to provide criteria for defining and establishing equivalent performance among accelerometers from different manufacturers. These research efforts are within the general guidelines on transducer equivalency outlined in the current revision of the Society of Automotive Engineers recommended practice, Instrumentation for Impact Test, SAE 211/2 March 1995. Representative data from vehicle crash and component level tests have been analyzed to determine the acceleration levels and frequency content in a realistic dynamic environment for dummy-based accelerometers.

Finite element (FE) modeling is becoming an integral approach to the study of crashworthiness of vehicle structures and occupant interaction with the structure. Crashworthiness assessment of a vehicle using numerical techniques necessitates the development of not only an accurate and representative vehicle model, but also a robust occupant model. This paper describes the development of mathematical models to perform the complete side impact simulation. The fully developed model can be used to evaluate occupant compartment intrusion and to assess occupant protection countermeasures in various side impact scenarios. A baseline finite element model of the side impact dummy (SID) used in the United States safety regulation, FMVSS 214, Side Impact Protection [7], was refined and calibrated using dynamic material and sub-system test data. Lower extremity geometry was reverse engineered and suitable material models and joints were incorporated in the revised model.