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This paper describes the National Highway Traffic Safety Administration's (NHTSA) efforts to determine how different outrigger designs can affect J-Turn and Road Edge Recovery test maneuver outcome. Data were collected during tests performed with three different outrigger designs (made from aluminum, carbon fiber, and titanium) having different physical properties (geometry and weight). Four sport utility vehicles were tested: a 2001 Chevrolet Blazer, 2001 Toyota 4Runner, 2001 Ford Escape, and a 1999 Mercedes ML320. The 4Runner and ML320 were each equipped with electronic stability control, however the systems were disabled for the tests performed in this study. A detailed description of the testing performed and the results obtained are discussed. From the results, a comparison of how the three outrigger designs affected the test results is provided.

In August of 2000, the National Highway Traffic Safety Administration (NHTSA) completed an Automated Collision Notification (ACN) Field Operational Test (FOT) in Erie County, New York, that combined crash sensing, position location, and wireless communications technology in a system with the goal of saving lives and reducing disabilities from injuries by providing faster and more informed emergency medical responses to serious injury crashes. The ACN FOT Team designed and built an ACN system prior to the start of the test period in July 1997. ACN in-vehicle systems were than installed in 850 vehicles. The crash notification messages were delivered to emergency response and dispatch equipment installed at the Erie County Sheriff's Office, which served as the Public Safety Answering Point (PSAP) for this FOT.

This paper describes the results of a study conducted to evaluate the performance and accuracy of a medium size sedan finite element model for off-set car-to-car impacts. This model was originally developed for front impact and does not include side structure compliance. Two tests conducted by the National Highway Traffic Safety Administration are used for evaluation of the simulations. The overall results indicate that the simulations appear to be consistent with the crash test data. Problems associated with the use of node constraints, lack of side structure model fidelity, and the different integration time marching are identified and solutions for the problems are proposed.

The injury reducing effectiveness of child safety seats in frontal crashes was evaluated, based on 36 frontal or oblique sled tests run with two or more GM three-year-old dummies in the simulated passenger compartment of a car. Unrestrained, correctly restrained and incorrectly restrained dummies were tested at the range of speeds where most nonminor injuries occur (15-35 mph). Accident data from NHTSA files were used to calibrate a relationship between the front-seat unrestrained dummies' HIC and unrestrained children's risk of serious head injuries; also between torso g's and the risk of serious torso injuries. These relationships were used to predict injury risk for the restrained children as a function of crash speed and to compare it to the risk for unrestrained children. The sled test analysis predicted that the 1984 mix of correctly and incorrectly used safety seats reduced serious injury risk by 40 percent relative to the unrestrained child, in frontal crashes.

A proposed modification to the Hybrid III 50th percentile male dummy upper femur appears to reduce the chest response problems resulting from femur-pelvis interaction in test exposures more severe than Standard No. 208 testing. When compared to overall repeatability of tests, the modification did not change other dummy response measurements appreciably. The femur-pelvis interaction problem, referred to as “hip lock”, was thought to occur in certain vehicles when the femurs of a passenger side dummy impacting only an air bag bottomed out against the pelvis structure. If metal-to-metal contact occurred, excessive load could be transferred to the chest, leading to elevated chest responses. The most pertinent signs of hip lock occurring appear to be a large, sharply pointed z chest acceleration, and a distinct positive component of the lumbar spine z force following the main negative component.

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.

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.

A comprehensive review of casualty-reducing effectiveness estimates of child safety seats in actual use, obtained by statistical analyses of highway accident data. Recent analyses of large samples of New York and Maryland accidents show statistically significant injury reductions for child safety seats; so does a new analysis of the National Highway Traffic Safety Administration's accident files. Results from Washington State, Tennessee, New Jersey, and Idaho are also reviewed, as are Nationwide restraint usage and fatality trends. The findings are critically examined for possible data biases. It is concluded that child safety seats definitely reduce deaths and injuries in highway crashes, but that their effectiveness cannot be accurately estimated at this time because of inconsistencies and possible biases in the various studies.

The fatality and injury reducing effectiveness of Tap belts for back seat occupants is estimated by applying the double pair comparison method to 1975-86 Fatal Accident Reporting System and 1982-85 Pennsylvania accident data. Lap belts significantly reduce the risk of fatalities by 17-26 percent, serious injuries by 37 percent, moderate to serious injuries by 33 percent and injuries of any severity by 11 percent, relative to the unrestrained back seat occupant. Lap belts are primarily effective in nonfrontal crashes because the unrestrained back seat occupant is already well protected in frontals. Lap belted occupants have lower head injury risk but higher torso injury risk than unrestrained back seat occupants. This paper presents the views of the author and not necessarily those of the National Highway Traffic Safety Administration (NHTSA).

This paper describes a Field Operational Test (FOT) of an Automated Collision Notification (ACN) System, a new way to provide definitive pre- hospital medical care to people injured in motor vehicle crashes. This FOT is part of the National Highway Traffic Safety Administration's (NHTSA's) research being conducted under the U.S. Department of Transportation's Intelligent Transportation Systems (ITS) program. Management of the program is by the Office of Vehicle Safety Research in NHTSA. The ACN FOT is a demonstration of the application of advanced technology for the improvement of pre-hospital emergency care for motor-vehicle crash victims. The test, involving approximately 850 volunteers' vehicles, was conducted in rural Western New York State. A partnership of local public agencies and private corporations, led by Veridian, Inc., performed the test.

The objectives of this study were to develop and apply procedures for defining pedestrian safety zones for the older (age 65+) adult and to develop, implement and evaluate a countermeasure program in the defined zones. Zone definition procedures were applied to two cities: Phoenix and Chicago. Extensive countermeasure programs were implemented in both cities. A complete crash-based evaluation was conducted only for the city of Phoenix where data showed significant reductions in zone crashes to 65+ pedestrians over a period in which the city's population and overall pedestrian crashes increased. It was concluded that the zone process resulted in an effective and efficient means of deploying pedestrian countermeasures for the older adult.

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.

NHTSA conducted seventy-six side impact FMVSS No. 214 compliance tests from 1994 through 1997. The compliance tests are nearly right angle side impacts with low longitudinal components of change of velocity (Δv). Frontal air bag deployments were found to have occurred for 34% of the driver bags and 32% of the front passenger bags in these compliance-tested passenger cars. In 1997, NHTSA began testing passenger cars 'in side impact in the New Car Assessment Program (NCAP). The NCAP crash tests are conducted at a higher speed than the compliance tests. The cars in the NCAP side impact tests also had low longitudinal components of Δv. Approximately 40% of the twenty-six passenger cars tested in the 1997 Side Impact NCAP had their frontal air bags deploy. Real world crash data were examined to determine if frontal air bags are deploying in right angle side impacts on the roads of the US.

This paper describes the assessment of driver interfaces of a type of electronics-based collision avoidance systems that has been recently developed to assist drivers of vehicles in avoiding certain types of collisions. The electronics-based crash avoidance systems studied were those which detect the presence of objects located on the left and/or right sides of the vehicle, called Side Collision Avoidance Systems, or SCAS. As many SCAS as could be obtained, including several pre-production prototypes, were acquired and tested. The testing focused on measuring sensor performance and assessing the qualities of the driver interfaces. This paper presents only the results of the driver interface assessments. The sensor performance data are presented in the NHTSA report “Development of Performance Specifications for Collision Avoidance Systems for Lane Changing, Merging, and Backing - Task 3 - Test of Existing Hardware Systems” [1].

Assessment of potential forearm fracture due to deployment of driver air bags is examined through a series of static air bag deployments with a specially instrumented Hybrid III dummy. The objective of the study was to determine the feasibility of measuring accelerations and bending moments on the Hybrid III dummy forearm as a potential injury index for arm fracture. Study of the National Accident Sampling System data has shown that in isolated circumstances, deployment of an air bag while the driver is making a turn can lead to fractures of the lower arm. To examine this phenomenon, the Hybrid III dummy was instrumented with accelerometers and strain gages to allow measurement of the accelerations and moments on the right arm. The arm was oriented over the steering wheel towards the eleven o'clock position during deployment of the air bag. Accelerations were measured on the arm at the wrist, elbow, and shoulder. Moments in two axes were measured at two locations below the elbow.

This study evaluated the response of restrained post-mortem human subjects (PMHS) in 40 km/h frontal sled tests. Eight male PMHS were restrained on a rigid planar seat by a custom 3-point shoulder and lap belt. A video motion tracking system measured three-dimensional trajectories of multiple skeletal sites on the torso allowing quantification of ribcage deformation. Anterior and superior displacement of the lower ribcage may have contributed to sternal fractures occurring early in the event, at displacement levels below those typically considered injurious, suggesting that fracture risk is not fully described by traditional definitions of chest deformation. The methodology presented here produced novel kinematic data that will be useful in developing biofidelic human models.

The absence of data on the load deflection and energy absorption characteristics of vehicle interiors has been a factor which limits the accuracy of crash victim simulations. A recent test program conducted for the National Highway Traffic Safety Administration has developed data on the interactions of dashboards and knee panels with chests and knees. This paper summarizes the test results for several vehicles and shows how these results are used in simulating vehicle crash tests. Comparisons between crash tests and computer reconstruction using the 3-Dimensional Crash Victim Simulator (CVS-3D) for a late model car are included. The simulation shows good agreement with test and illustrates the application of available static and dynamic test data to improve occupant simulations.

In the United States, air bags will be required in all passenger cars and light trucks under Federal Motor Vehicle Safety Standard (FMVSS) No. 208, Occupant Crash Protection. Even after full implementation of driver and passenger air bags as required by FMVSS No. 208, frontal impacts will still account for up to 8,000 fatalities and 120,000 moderate to critical injuries (i.e., injuries of AIS ≥ 2) [1]. The National Highway Traffic Safety Administration (NHTSA) has an ongoing research program to address these fatalities and injuries and provide a basis for the possible future upgrade of FMVSS No. 208. This effort includes developing supplementary test procedures for the evaluation of occupant injury in higher severity crashes, developing improved injury criteria including criteria for assessing injuries to additional body regions, and evaluating the injuries associated with occupant size [2, 3 and 4].

Currently, consumers must contend with many comfort and convenience problems whenever they use a manually operated (“active”) safety belt. Such problems are prevalent not only in older models but in new cars as well. Beginning with 1982 models, most auto manufacturers plan to install automatic safety belts to meet new Federal requirements for passive occupant protection. To reduce the likelihood of consumer rejection and non-use of automatic as well as manual belt systems, research has been conducted to develop performance specifications for improved comfort and convenience. This paper discusses specifications and criteria to improve the safety belts by reducing comfort and convenience variables for both manual and automatic systems.