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The objective of this study was to analyze the position of the shoulder belt and adjustable upper anchorage (AUA) relative to the occupant in recent (2011-2012) NHTSA NCAP frontal crash tests. Since 2011, certain changes have been made in the NCAP test procedure. These changes include different Hybrid III occupant sizes as well as variations in the methods for calculating injury risk. One of the most significant changes has to do with thoracic injury risk calculation which was previously associated with chest acceleration and is now based on chest deflection as the measurable parameter. Using the NHTSA NCAP database, as well as other crash test data sources, a comparison was made between the designated upper anchorage position prior to a crash test and the actual position of the belt webbing with respect to the chest deflection measurement potentiometer sub-assembly of the Hybrid III.

Based on a long recognized need, the National Highway Traffic Safety Administration (NHTSA) has begun to reexamine the potential for international harmonization of side impact requirements. To this end, NHTSA, as directed by the U.S. Congress, has recently submitted a report to the Congress on the agency plans for achieving harmonization of the U.S. and European side impact regulations. The first phase of this plan involves crash testing vehicles compliant to FMVSS 214 to the European Union side impact directive 96/27/EC. This paper presents the results to date of this research. The level of safety performance of the vehicles based on the injury measures of the European and U.S. side impact regulations is assessed.

An upgrade of EUROSID-1, the side impact dummy used in the European Union Side Impact Directive 96/EC/27, was recently developed by TNO to address dummy response issues raised by industrial and governmental bodies, in particular, the flat-top anomaly in the rib deflections. NHTSA is evaluating the ES-2 dummy, the upgraded EUROSID-1, to assess its performance in the FMVSS 214 test configuration. This paper presents results from NHTSA's testing of the ES-2 including high mass pendulum impactor tests using three proposed rib designs, biofidelity sled tests comparing the ES-2 and U.S. SID, and full-scale side impact tests.

Several thoracic and head protection side impact air bag systems (SAB) are emerging in the U.S. market and are projected to become prevalent in the fleet. These systems appear to offer superior protection in side crashes. However, concerns have been raised as to their potential for causing injury to out-of-position (OOP) occupants. This paper describes the National Highway Traffic Safety Administration (NHTSA) program for evaluation of the SAB systems for OOP occupants and provides a status report on the current research. The industry's Side Airbag Out-of- Position Injury Technical Working Group (TWG) recommended procedures for 3-year-old and 6-year-old occupants are evaluated. Additional test procedures are described to augment the TWG procedures for these occupants and 12-month- old infants.

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.

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.

This study tracks vehicle design changes and frontal crash test performance in NHTSA's NCAP and IIHS consumer information tests since the mid-90s for the Honda Accord and Toyota Camry. The objective was to provide insights into how passenger cars have changed in response to frontal consumer information tests. The history of major design changes for each model was researched and documented. The occupant injury measures from both NHTSA and IIHS were computed and the ratings compiled for several generations of both vehicles. Changes in vehicle crash pulse and occupant injury measures from both NCAP and IIHS tests, and from Canadian low speed rigid barrier tests, when available, were used to assess driver frontal protection for various vehicle generations. Loading of the rigid barrier in NCAP tests was used to evaluate front end stiffness changes over the years.

An overview NASS study of US frontal crashes was performed to investigate crash involvement, driver injury distributions and rates in airbag equipped vehicles by vehicle class and structural engagement. Frontal crash bins were based on taxonomy of structural engagement, i.e., Full Engagement, Offset, Between Rails and Corner impact crashes. A new classification of Corner impacts included frontal small overlap impacts with side damage as coded by NASS CDS. Belted drivers of two age groups, between 16 and 50 and over 50 years old, were considered. Vehicles were grouped into light and heavy passenger cars and lights trucks, and vans. A method to identify and address overly influential NASS weights was developed based on considerations of weighting factor statistics. The new taxonomy, with an expanded definition of corner impacts, allowed a more comprehensive classification of frontal crash modes.

Evaluation of safety benefits is an essential task during design and development of pedestrian protection systems. Comparative evaluation of different safety concepts is facilitated by a common metric taking into account the expected human benefits. Translation of physical characteristics of a collision, such as impact speed, into human benefits requires reliable and preferably evidence-based injury models. To this end, the dependence of injury severity of body regions on explanatory factors is quantified here using the US Pedestrian Crash Data Study (PCDS) for pedestrians in frontal vehicle collisions. The explanatory and causal factors include vehicle component characteristics, physiological and biomechanical variables, and crash parameters. Severe to serious injuries most often involve the head, thorax and lower extremities.