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Many newer commercial vehicles have an event data recorder (EDR) that can record pre-event and post-event speeds. The EDR is incorporated into the engines electronic control module (ECM). In this study, the accuracy of the ECM-reported speed was tested during acceleration, gear shifting and braking at speeds between 16 and 88 km/h (10 to 55mph). The ECM-reported speed was compared to the speed measured by a calibrated optical 5th wheel. The results showed that the accuracy of the ECM-reported speed matched closely during acceleration, cycled to periods of under-reporting the speed during hard braking due to the ABS brake function, briefly under-reporting the speed after letting off the throttle for braking or gear shift and briefly over-reporting the speed near the end of a gear shift phase. This study also looked at calibration factors of the ECM and their effect on the ECM-reported speed.

The U.S. National Highway Transportation and Safety Agency's (NHTSA) early estimates of Motor Traffic Fatalities in 2009 in the United States [1] show continuing progress on improving traffic safety on the U.S. roadways. The number of total fatalities and the fatality rate per 100 Million Vehicle Miles (MVM), both show continuing declines. In the 10 year period from 1999 through 2009, the total fatalities have dropped from 41,611 to 33,963 and the fatality rate has dropped from 1.5 fatalities per 100MVM to 1.16 fatalities per 100MVM, a compound annual drop of 2.01% and 2.54% respectively. The large number of traffic fatalities, and the slowing down of the fatality rate decline, compared to the decade before, continues to remain a cause of concern for regulators.

This is an overview of air bag injuries, a review of the literature and descriptions of air bag related injuries to the various body areas. Some unusual injuries are also included. The cases presented are from the author's files and one from the Special Studies Division of NHTSA.

Worldwide, 1.2 million people die in road crashes yearly; 43,000 in Europe alone. This implies a cost to European society of approximately 160 billion euros, and takes up 10% of all healthcare resources. To reduce these rates, safety technologies have been developed which help to minimize the severity of injuries to vehicle occupants. However, studies have shown that most deaths due to road accidents occur in the time between the accident and the arrival of medical care. Therefore, a fast and efficient rescue operation would significantly increase the injured person's probability of survival. The aim of this project was to define the On-Board Unit (OBU) hardware and software installed in all modern vehicles which could request medical and technical support after a road accident. This device, based on the information from the vehicle sensors, automatically decides whether the car has suffered a road accident or not, the severity of the accident and the kind of accident (impact area).

The effect of vehicle acceleration history on dummy loading in the frontal impact NCAP event is explored with help of a one-dimensional mathematical model. Both numerical and analytical approaches are used to identify the ideal vehicle pulse. The numerical solution reveals limitations of square wave pulse. The analytical approach results in explicit formulation of the ideal pulse. Response of the mathematical model used in this paper is statistically correlated to a number of randomly selected NCAP frontal tests. Both the baseline model and the resulting optimized pulse are also confirmed using a validated three-dimensional Madymo model. Based on the analytical results, a simple measure of quality of the vehicle acceleration history is formulated.

A new chain saw powered by rotary engine has been developed with a view to prevent the current injuries due to vibration from chain saws. This paper covers the construction of the rotary engine and performances of the new chain saw including vibration measurements. Vibration acceleration of the new chain saw shows so low level compared with reciprocating engine saws that it would be quite promising for prevention of the vibration injuries.

During most pedestrian-vehicle crashes the car front impacts the pedestrian and the whole body wraps around the front shape of the car. This influences the head impact on the vehicle. Meanwhile the windscreen is a major impact point and tested in NCAP conditions. The severity of injuries is influenced by car impact speed; type of vehicle; stiffness and shape of the vehicle; nature of the front (such as the bumper height, bonnet height and length, windscreen frame); age and body height of the pedestrian; and standing position of the pedestrian relative to the vehicle front. The so called Wrap Around Distance WAD is one of the important measurements for the assessment of protection of pedestrians and of bicyclists as well because the kinematic of bicyclists is similar to that of pedestrians. For this study accidents of GIDAS were used to identify the importance of WAD for the resulting head injury severity of pedestrians and bicyclists.

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situations including the worst cases such as rollover, spin-out and so on. Although the known NHTSA J-turn and Fish-hook steering maneuvers are applied for the vehicle performance assessment, they are not enough to predict other possible worst case scenarios. Therefore, it is crucial to search for the various worst cases including the existing severe steering maneuvers. This paper includes the procedure to search for other useful worst case based upon the existing worst case scenarios in terms of rollover and its application in simulation basis. The human steering angle is selected as a design variable and optimized to maximize the index function to be expressed in terms of vehicle roll angle. The obtained scenarios were enough to generate the worse cases than NHTSA ones.

The results of biomechanical testing of the WorldSID prototype dummy are presented in this paper. The WorldSID dummy is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. The first prototype of this dummy has been evaluated by the WorldSID Task Group against previously established corridors for its critical body regions. The response corridors are defined in the International Organization of Standardization (ISO) Technical Report 9790. The prototype is the first version of the WorldSID dummy to be built and tested. This dummy has been subjected to a rigorous program of testing to evaluate, first and foremost its biofidelity, but also its repeatability. Following this initial evaluation, any required modifications will be incorporated into a pre-production version of the WorldSID dummy so that it rates “good” to “excellent” on the ISO dummy biofidelity scale – a rating exceeding that of all current side impact dummies.

Accident studies indicate that serious neck injuries are generally infrequent in side crashes. However, given the rapid changes in side impact protection technology, such as side airbags and curtain systems, the nature of head-neck interactions is likely to change. Consequently, the newest generation of anthropomorphic test devices for side impact should provide realistic prediction of the head-neck kinematics and include meaningful measurements related to risk of head and neck injury. The WorldSID dummy has been assessed against a set of five test conditions that have been used to define biofidelity impact response targets. Three of the five test conditions are recommended by ISO TR9790 (ISO 1997), the NBDL 7.2 G, 6.9 m/s lateral sled impact reported by Ewing et al. (1977) and Wismans et al. (1986), the Patrick and Chou lateral, 6.7 G 5.8 m/s (1976) and Tarriere lateral 12.2 g, 6,1 m/s sled impact (ISO 1997).

A series of carefully controlled simulated barrier crashes at speeds from 20 to 30 mph are used to compare the relative safety of rubber gasket, butyl tape and polysulfide adhesive methods of installing windshields. Only subtle differences were found in the severity index and the laceration index. There is an indication that the rubber gasket installation has a higher resistance to interlayer tears and the lacerations from impacts to polysulfide installations are slightly more severe. Head attitude at impact was found to have a significant effect on interlayer tears and resultant lacerations.

A series of low-speed static and dynamic wind tunnel tests of a commercial transport configuration over an extended angle of attack/sideslip envelope was conducted at NASA Langley Research Center. The test results are intended for use in the development of an aerodynamic simulation database for determining aircraft flight characteristics at extreme and loss-of-control conditions. This database will be used for the development of loss-of-control prevention or mitigation systems, pilot training for recovery from such conditions, and accident investigations. An overview of the wind-tunnel tests is presented and the results of the tests are evaluated with respect to traditional simulation database development techniques for modeling extreme conditions to identify regions where simulation fidelity should be addressed.

It is becoming apparent that some safety devices are performing their desired function rather well while others are not. The one quality that all the better designs have is they require no action on the part of the occupant to perform their safety function in the event of a crash, that is, they are passive. Presently, the most viable passive restraint is the air bag. It inherently offers convenience and reliability characteristics which will appeal to the general public. Active restraints, such as the adjustable head restraint, ignition-interlock and lap/shoulder belt have consistently shown by their usage figures that they are unacceptable to the public.

There is no reason why highway loss reduction countermeasure priorities must parallel the rank of causes. Traditional emphasis only on crash prevention ignores major opportunities for reducing losses to damaged people and property. A standard method is needed for rating vehicles' occupant protection considering limits set by physics and body force tolerances. The use of structural damage for crash energy absorption, particularly at 5 to 20 m.p.h., is archaic in comparison with aircraft strut design. It is predicted that the present, structural-damage approach to low speed energy absorption will soon become publicly unacceptable.

NHTSA's Fatal Crash Reporting System (FARS) collects information on all US fatal public roadway motor vehicle crashes.1 However, FARS contains only the information “K”(killed) as injury information for the individuals sustaining fatal injuries. This paper discusses how a 100 fold improvement in injury detail can be obtained with ICD-9 mortality information by linking FARS with the Vital Statistics Multiple Cause of Death (MCOD) database.2 This link, developed by NHTSA, is accomplished on an individual by individual basis. The FARS database contains about 40,000 individuals killed per year, and nearly 25 years of data available. A multi-year linked FARS-MCOD database can contain detailed cause of death for more than 1,000,000 motor vehicle fatalities. The linked FARS-MCOD allows the reasons why people die in MVC to be studied down to specific vehicle make/model combinations.

The literature contains a wide range of response data describing the biomechanics of isolated body regions. Current data for the validation of frontal anthropomorphic test devices and human body computational models lack, however, a detailed description of the whole-body response to loading with contemporary restraints in automobile crashes.

The objective of the current study was to provide a comprehensive characterization of human biomechanical response to whole-body, lateral impact. Three approximately 50th-percentile adult male PMHS were subjected to right-side pure lateral impacts at 4.3 ± 0.1 m/s using a rigid wall mounted to a rail-mounted sled. Each subject was positioned on a rigid seat and held stationary by a system of tethers until immediately prior to being impacted by the moving wall with 100 mm pelvic offset. Displacement data were obtained using an optoelectronic stereophotogrammetric system that was used to track the 3D motions of the impacting wall sled; seat sled, and reflective targets secured to the head, spine, extremities, ribcage, and shoulder complex of each subject. Kinematic data were also recorded using 3-axis accelerometer cubes secured to the head, pelvis, and spine at the levels of T1, T6, T11, and L3. Chest deformation in the transverse plane was recorded using a single chestband.

A new, articulated, 4-wheel drive agricultural tractor has been developed which combines the advantages of 2-wheel drive tractors with the advantages of full-time, 4-wheel drive tractors with equal-size wheels. To accomplish this, the tractor incorporates a unique drivetrain and frame arrangement. An unusual cab-mounting arrangement is also used that reduces the chance of serious injury in the event of a rollover.

The number of whiplash accidents is an appreciable portion in the total automobile accidents. The purpose of this study is to measure the impact in very low-speed vehicle collisions and to clarify the mechanism of whiplash in low accelerations. In low-speed collisions, the change of total momentum of both vehicles before and after a collision cannot be considered to be nil but equals to the impulse of tire friction and rolling resistance. Consequently, the acceleration of struck vehicle depends on whether the emergency brake is applied or the engine stalls during a collision. The neck of a dummy was modified for the whiplash studies and the improved neck is found to well duplicate human passengers by comparing dummy's head motions with already reported human and cadaver experiments. It was found by the study that a head-rest and an elastic bumper stay are very effective to prevent whiplash for low speed rear-end collisions of few km/h.

This publication looks at whiplash from a variety of perspectives. A compendium of technical presentations, Whiplash Injuries is broken into four parts: General Aspects Physiopathology Evaluation and Treatment Published by Springer-Verlag. Distributed by SAE.