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The goal of this paper is to estimate near-side injury risk in vehicles with the best side impact performance in the U.S. New Car Assessment Program (NCAP). The longer-term goal is to predict the incidence of crashes and injury outcomes in the U.S. in a future fleet of the 2025-time frame after current active and passive safety countermeasures are fully implemented. Our assumption was that, by 2025, all new vehicles will have side impact passive safety performance equivalent to current U.S. NCAP five star ratings. The analysis was based on real-world crashes extracted from case years 2010-2015 in the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS) in which front-row occupants of late-model vehicles (Model Year 2011+) were exposed to a near-side crash.

To date, efforts to improve occupant protection in side impact crashes have concentrated on reducing the injuries to occupants seated on the struck side of the vehicle arising from contact with the intruding side structure and/or external objects. Crash investigations indicate that occupants on the struck side of a vehicle may also be injured by contact with an adjacent occupant in the same seating row. Anecdotal information suggests that the injury consequences of occupant-to-occupant impacts can be severe, and sometimes life threatening. Occupant-to-occupant impacts leave little evidence in the vehicle, and hence these impacts can be difficult for crash investigators to detect and may be underreported. The objective of this study was to evaluate the risk of impact injury from occupant-to-occupant impacts in side impact vehicle crashes. The study examined 9608 crashes extracted from NASS/CDS 1993-2006 to investigate the risk of occupant-to-occupant impacts.

Pediatric Anthropomorphic Test Devices (ATDs) are valuable tools for assessing the injury mitigation capability of automotive safety systems. The neck pendulum test is widely used in biofidelity assessment and calibration of the ATD neck, and neck moment vs. angle response requirements are the metrics typically derived from the test. Herein, we describe the basis and methods for modifying the neck pendulum such that it more closely reflects base of the neck accelerations observed by a restrained three-year old ATD in a frontal crash. As a measure of base of the neck acceleration, the x-direction chest acceleration from thirty-one restrained Hybrid III three-year-old ATDs in vehicle frontal crash tests were analyzed. The standard neck pendulum yielded a mean peak acceleration that is 1.2x the peak of vehicle base of the neck accelerations, 1.6x the average, and 0.24x the duration.

This paper uses the National Automotive Sampling System/Crashworthiness Data System (NASS/CDS) to estimate the population of front seat occupants exposed to far-side crashes and those with MAIS 3+ and fatal injuries. Countermeasures applicable to far-side planar crashes may also have benefits in some far-side rollovers. The near-side and far-side rollover populations with MAIS 3+ injuries and fatalities are also calculated and reported. Both restrained and unrestrained occupants are considered. Populations are subdivided according to ejection status – not ejected, full ejection, partial ejection and unknown ejection. Estimates are provided for the annual number of MAIS 3+ injuries and fatalities that occur each year in each category for the following belt use scenarios: (1) belt use as reported in NASS and (2) 100% belt use. In scenario 1, the exposure and casualties for the unbelted population are also shown. About 34% of the MAIS 3+F injuries in side crashes are in far-side crashes.

In a side impact, the occupants on both the struck, or near side, of the vehicle and the occupants on the opposite, or far side, of the vehicle are at risk of injury. Since model year 1997, all passenger cars in the U.S. have been required to comply with FMVSS No. 214, a safety standard that mandates a minimum level of side crash protection for near side occupants. No such federal safety standard exists for far side occupants. The mechanism of far side injury is believed to be quite different than the injury mechanism for near side injury. Far side impact protection may require the development of different countermeasures than those which are effective for near side impact protection. This paper evaluates the risk of side crash injury for far side occupants as a basis for developing far side impact injury countermeasures. Based on the analysis of NASS/CDS 1993–2002, this study examines the injury outcome of over 4500 car, light truck, and van occupants subjected to far side impact.

The primary description of crash severity in most accident databases is vehicle delta-V. Delta-V has been traditionally estimated through accident reconstruction techniques using computer codes, e.g. Crash3 and WinSmash. Unfortunately, delta-V is notoriously difficult to estimate in many types of collisions including sideswipes, collisions with narrow objects, angled side impacts, and rollovers. Indeed, approximately 40% of all delta-V estimates for inspected vehicles in the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS) 2001 are reported as unknown. The Event Data Recorders (EDRs), now being installed as standard equipment by several automakers, have the potential to provide an independent measurement of crash severity which avoids many of the difficulties of accident reconstruction techniques. This paper evaluates the feasibility of replacing delta-V estimates from accident reconstruction with the delta-V recorded by EDRs.

Several research studies have concluded that light trucks and vans (LTVs) are incompatible with cars in traffic collisions. These studies have noted that crash incompatibility is most severe in side crashes. These early research efforts however were conducted before complete introduction of crash injury countermeasures such as dynamic side impact protection. Based upon U.S. traffic accident statistics, this paper investigates the side crash compatibility of late model cars, light trucks and vans equipped with countermeasures designed specifically to provide side crash protection. The paper explores both LTV-to-car crash compatibility and crash incompatibility in car-to-car collisions.

Light trucks and vans (LTVs) currently account for over one-third of registered U.S. passenger vehicles. Yet, collisions between cars and LTVs account for over one half of all fatalities in light vehicle-to-vehicle crashes. Nearly 60% of all fatalities in light vehicle side impacts occur when the striking vehicle is an LTV. This paper will examine this apparent incompatibility between cars and LTVs in traffic crashes. An analysis of U.S. crash statistics will be presented to explore the aggressivity of LTVs in impacts with cars and identify those design imbalances between the cars and LTVs, e.g., mass, stiffness, and geometry, which lead to these severe crash incompatibilities.

A new numerical model of the side impact dummy (SID) was developed based on the DYNA3D finite element code. The model includes all of the material and structural details of SID that influence its performance in crash testing and can be run on an engineering work station in a reasonable time. This paper describes the development of the finite element model and compares model predictions of acceleration and displacements with measurements made in SID calibration experiments. Preliminary parameter studies with the model show the influence of material properties and design on the measurements made with the SID instrument.

The National Highway Traffic Safety Administration (NHTSA) has developed a lumped mass computer model which simulates the interaction of a struck car door and an adjacent two dimensional seated dummy in side impacts. This model was used to investigate the effect of various vehicle design parameters on occupant responses and to define various methods to improve vehicle safety performance. This paper discusses the effectiveness of door padding and side structural stiffness to minimize potential for occupant thoracic injuries in 90° side impacts. Occupant response data were obtained with the aid of the computer model for a Moving Deformable Barrier striking a car at lateral velocities of 25, 30 and 35 mph. To determine the optimal padding and structure needed to minimize potential occupant injury, the Thoracic Trauma Index (TTI) was mapped in terms of different levels of struck car side stiffness and padding characteristics.

Since the 1984 publication of the results of NHTSA's initial research on thoracic side impact protection, substantial progress has been made. Specifically, the NASS data have been reviewed relative to side impacts, an updated injury criterion has been developed, the MVMA has conducted a very significant crash test project, and the NHTSA has conducted additional full system production vehicle tests. The review of the NASS data and a comparison with the previously used NCSS data indicate the thoracic injury remains the highest ranking injury in non-rollover, non-ejection side impacts. The updated injury criterion, TTI-86, is applied to the side impact dummies in the modified vehicle tests which have been conducted by NHTSA and MVMA. The TTI-86 is also applied to twenty production vehicle tests which have been conducted by NHTSA. The improved performance of the modified vehicles is compared to the average performance of the twenty production vehicles.