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For years, reducing the number of traffic-related fatalities and injuries has been a major problem throughout the world. Today, it has gained much more momentum in view of rapidly increasing SUV, van, and light-truck populations relative to the number of passenger cars, and due to significant improvements in technologies that facilitate a better understanding of the interaction dynamics among widely differing size vehicles. Unless disparities in crashworthiness among vehicles of different masses, sizes, and structural characteristics in mixed crash environments are successfully taken into account, the challenge toward improved vehicle safety will continue. This two-part compendium provides the most comprehensive information available on the entire spectrum of vehicle crash compatibility. The first part presents oral comments captured from the 2003 SAE World Congress panel discussion on compatibility.

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.

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.

Locations of key body segments of Hybrid III dummies used in FMVSS 208 compliance tests and NCAP tests were measured and subjected to statistical analysis. Mean clearance dimensions and their standard deviations for selected body segments of driver and passenger occupants with respect to selected vehicle surfaces were determined for several classes of vehicles. These occupant locations were then investigated for correlation with impact responses measured in crash tests and by using a three dimensional human-dummy mathematical model in comparable settings. Based on these data, the importance of some of the clearance dimensions between the dummy and the vehicle surfaces was determined. The study also compares observed Hybrid III dummy positions within selected vehicles with real world occupant positions reported in published literature.

In 1983, the National Highway Traffic Safety Administration (NHTSA) initiated two air hag vehicle fleet programs. The objective was to demonstrate that both original equipment and retrofit air bag systems operate in vehicles as intended. As of July 1, 1987, the two fleets together have accumulated over 200 million miles. Data are presented for 112 crashes involving air bag deployment in these government sponsored fleet vehicles in service between 1984 and July 1, 1987. Of the 112 drivers involved in the crashes, 103 sustained either no injury or only minor (AIS 1)[1]1 injuries. Of the nine remaining cases, six were AIS 2 and three AIS 3. To date, the limited data indicate that the air bag deployed as expected in all frontal crashes severe enough to require occupant restraint beyond that provided by the vehicle interior. Additionally, in collisions in which the air bag did not deploy, the crashes were of such low severity that no actuation was expected and none took place.

This two part study investigates differences in thorax deflections between volunteers and dummies when they are dynamically loaded by diagonal shoulder belts and it shows how internal measurements at the Hybrid III dummy's sternum relate to external compressions at various points of the rib cage. Test results reveal that the thorax of the Hybrid III dummy, when loaded by a diagonal belt, is somewhat stiffer than that of volunteers for both tensed and relaxed conditions. The thorax of volunteers under dynamic belt loading deflects underneath the belt in an action similar to that of a flat rigid plate being pushed into the thorax with increasing deflection towards the lower part of the ribcage, while the dummy's deflected profile assumes a parabolic curvature.

This paper addresses the kinematics of occupants of light motor vehicles that are involved in frontal collisions. Injury to occupants of these vehicles constitute a majority of the harm incurred in all of the traffic accidents. Host injury is caused by the relatively high velocity collisions of occupants into vehicle interior components. A two dimensional (2-D) MVMA dynamic occupant simulation was used to facilitate the understanding of occupant kinematics in frontal collisions in general and to determine the spectra of occupant impact velocities into vehicle components for a range of crash speeds in particular. Real world accident data and laboratory crash tests were used to provide inputs and boundaries for the MVMA 2-D model. The accident data provided guidelines as to which occupant-to-vehicle impact modes produce the most harm and therefore should be addressed.

Parallel and coordinated accident studies were conducted in the United States and in the Federal Republic of Germany to determine the extent, the level, and the comparability of neck injuries in automotive accidents as reported in the National Crash Severity Study (NCSS), and the Association of German Automobile Insurers (HUK-Verband) files. To determine the comparability of the two data sets, three primary evaluation criteria were used: 1) the distribution of overall injuries by AIS level by various occupant parameters, 2) the risk of occupant AIS injury vs. delta V, and 3) the distribution of neck injuries by AIS for restrained vs unrestrained occupants. Frequencies and severities of neck injuries in car accidents were compared in parallel layouts between the two data sets in frontal, side and rear impact modes. In further breakdown the frontal impact file was separated into driver/passenger and male/female categories.

A solid state, low power, self-contained digital crash recorder was developed and installed in the Part 572 crash test dummy for capturing and storing the crash severity-time event. The crash recorder is capable of recording upon internal triggering command the dummy's response in 10 separate data channels. The recorder's performance was evaluated in laboratory and vehicle tests consisting of simulated and real rigid barrier collisions in the forward impact mode and moving barrier collisions in side impacts. The recorder was found to be suitable for capturing and storing high quality crash data compatible with currently used hardwire data acquisition techniques.

A three-part program was undertaken to establish an appropriate means of evaluating child restraints in automobile crashes. A standard seat was designed to provide a reproducible test base on which to evaluate child restraint systems in dynamic testing. Developmental and evaluation data are presented, including child restraint performance tests. Results showed the standard seat to be a durable, repeatable, and economical test platform which provides a realistic base for evaluation of child restraint systems. Commercially available three- and six-year-old child dummies were evaluated for their anthropometric measurements and dynamic response characteristics in pendulum impact tests and simulated crashes in representative automobile-child seat restraint environments. Simulated crashes included 20 and 30 mph frontal and 20 mph side impacts on automobile and specially designed bench seats. Two types of child seats, the G. M.

The sensitivity of response of crash victim simulation was investigated using a two-dimensional, mathematical eight-mass model. The model was exercised in the forward collision mode in a three-point restraint system using a trapezoidal forcing function. Mass and inertia parameters of the occupant simulation, its setup, and the restraint and environment systems were evaluated individually and as groups, in terms of their effects on the occupant's head and chest acceleration. The study also investigates and rates the effects of shape and time duration of the forcing function upon the response of the occupant.

The authors summarize information on effects of tires on tandem truck ride and vibration problems. An appraisal of research and a request to face the challenge of acquiring better engineering measurements of vehicle vibration are given.