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Technical Paper

Whiplash: Tests of the Influential Variables

The effect of seat back rotation, head restraint position, and collision speed on crash dummy head acceleration, extension and flexion was determined by tests using an acceleration sled and vehicle collisions. The sled tests were run with a rigid seat and an adjustable back at 10, 20, and 30 mph. Vehicle collisions were conducted with production seats with and without head restraint devices at 10, 15, 20, 25, 30, 40, and 50 mph impact speeds. Fifty percentile adult male Sierra dummies were used. The head was able to move freely when accelerated backward. In both sled and vehicle collisions, head restraint devices reduced the measured severity criteria on the crash dummies employed in the tests.
Technical Paper

White Farm Equipments 4-150 Field Boss

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.
Technical Paper

Whole-Body Human Surrogate Response to Three-Point Harness Restraint

The general objective of the whole-Body Response (WBR) research program was to generate data on the kinematics and response of human surrogates in a realistic automobile impact environment. The program used a test configuration consisting of an idealized hard seat representation of a car seat with a three-point harness restraint system. Three different severity levels of crash test conditions were used. The human surrogates tested in this program were fifteen male cadavers*, a Hybrid II (Part 572) Anthropomorphic Test Device and a Hybrid III ATD recently developed by General Motors. In addition, mathematical simulations of the response and kinematics of a 50th percentile male occupant were performed at the three levels of crash severity, using the MVMA Two-Dimensional Crash Victim Simulator.
Technical Paper

Whole-Body Response to Pure Lateral Impact

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.
Technical Paper

Whole-body Kinematic and Dynamic Response of Restrained PMHS in Frontal Sled Tests

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.
Technical Paper

Whole-body Response for Pedestrian Impact with a Generic Sedan Buck

To serve as tools for assessing injury risk, the biofidelity of whole-body pedestrian impact dummies should be validated against reference data from full-scale pedestrian impact tests. To facilitate such evaluations, a simplified generic vehicle-buck has been recently developed that is designed to have characteristics representative of a generic small sedan. Three 40 km/h pedestrian-impact tests have been performed, wherein Post Mortem Human Surrogates (PMHS) were struck laterally in a mid-gait stance by the buck. Corridors for select trajectory measures derived from these tests have been published previously. The goal of this study is to act as a companion dataset to that study, describing the head velocities, body region accelerations (head, spine, pelvis, lower extremities), angular velocities, and buck interaction forces, and injuries observed during those tests.
Technical Paper

Why People Die in Motor Vehicle Crashes: Linking Detailed Causes of Death with FARS Data

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.
Technical Paper

Why the Issue Is Loss Reduction Rather than Only Crash Prevention

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.
Technical Paper

Why your best life insurance is a passive restraint

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.
Technical Paper

Wind-Tunnel Investigation of Commercial Transport Aircraft Aerodynamics at Extreme Flight Conditions

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.
Technical Paper

Windshield Injury Potential as a Function of Windshield Installation Method

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.
Technical Paper

WorldSID 5th Percentile Prototype Dummy Development

The WorldSID 5th percentile dummy, representing an average female, was developed in less than three years after the WorldSID 50th percentile dummy production release. This 5th percentile dummy was developed in the Integrated Project Aprosys (Advanced Protection Systems) under the European Commission Framework Program 6. This paper discusses the rationale for the WorldSID 5th percentile dummy design and development, and biofidelity evaluation results of head drop test, neck pendulum test and pendulum impact tests of the shoulder, thorax, abdomen and pelvis according to ISO TR9790 (ISO 1997) and Irwin (2002). The dummy was designed to host four units of 32 channel in-dummy Data Acquisition System with total 128 channel capacity. The head is constructed with PVC skin and plastic skull to simulate human head structure. The neck consists of a rubber design with metal discs, which can be tuned with rubber buffers.
Technical Paper

WorldSID Dummy Head-Neck Biofidelity Response

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).
Technical Paper

WorldSID Prototype Dummy Biomechanical Responses

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.
Technical Paper

Worst Case Scenarios Generation and Its Application on Driving

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.
Technical Paper

Wrap Around Distance WAD of Pedestrian and Bicyclists and Relevance as Influence Parameter for Head 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.
Technical Paper

X-Ray Curing of Carbon Fiber Composites for Structural Automotive Components

Having demonstrated the feasibility of using X-rays derived from high current industrial electron beam accelerators (EB) to cure the matrices of carbon fiber composites and then scaled this up to cure large sized, non-structural automobile components, performance car hoods, the New York State Vehicle Composites Program had a chassis designed, a cured epoxy mold made and then the chassis matrix cured using X-rays with a formulated radiation responsive matrix material. A feasibility study had shown how X-rays could cure through materials embedded within the composite layers, such as metal inserts that could be used for mechanical fastening without fracturing the composite. In producing X-ray cured hoods, the power consumption for X-ray curing was found to be more than 20% lower than that needed for autoclave curing the same sized hoods using conventional thermosetting pre-pregs. More significant was the time-to-cure.
Technical Paper

X-Ray Study of the Human Neck Motion Due to Head Inertia Loading

This study presents results from x-ray analysis of live human head/neck motion in sled test simulations of low-speed frontal, lateral, and rear-end vehicle impacts. The test subjects were 26 male and female adults, aged 22 to 61 years. Head/neck motion and the kinematic responses of each test subject were measured and analyzed by cineradiograph, high-speed film, accelerometers, and electromyography of the neck muscles. The methodology used may provide insight into the mechanism of neck injuries caused by the head inertia loading. The actual kinematic responses of the head/neck were found to be more complex than previously thought. The experimental results suggest that the most significant factor of the head/neck response is the initial curvature of the cervical and thoracic spine. Looking specifically at the early motion of the head and neck in rear-end impacts, the cervical forward curvature (lordosis) and the thoracic rearward curvature (kyphosis) were found to straighten.
Technical Paper

Yanmar Diesel's Rotary Engine Chain Saw

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.
Technical Paper

Yet Another Look At Crash Pulse Analysis

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.