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Recent models of General Motors (GM) and selected Ford vehicles may be equipped with an event data recorder (EDR) that records information in the airbag sensing and diagnostic module (GM-SDM) or restraint control module (Ford-RCM). These systems have become a resource to the accident reconstructionist in the analysis of collisions involving data recorder equipped vehicles, as typically the data can be downloaded via the Vetronix Crash Data Retrieval (CDR) System. The purpose of this paper is to investigate the use of the CDR System in pedestrian accidents. A series of impacts using a pedestrian dummy and SDM equipped vehicles were performed. After each test, the SDM was downloaded via the CDR system and the data evaluated. The dummy and vehicle kinematics were documented and the vehicle impact response was compared with the SDM recorded velocity change and impact speed.

In past years, considerable research has been devoted to occupant response in a variety of low-velocity, bumper-to-bumper impacts. In many crashes, however, the involvement of a braking vehicle or a higher ground clearance vehicle results in an override/underride type crash. The amount of vehicle damage can be significantly greater during such an impact because of the involvement of non-structural components above and below the bumper systems of the involved vehicles. Ten tests were conducted using five target vehicles, each occupied by an instrumented female driver. Each vehicle was tested in a bumper-to-bumper impact and then an override/underride configuration in increasing severity. An independent body shop estimator was employed to document the damage and prepare repair estimates for each test. In each test the vehicle and occupant accelerations were monitored.

A search of the automotive collision trauma literature reveals that over the last 35 years shows that there have been less than ten published Society of Automotive Engineers (SAE) articles describing the collision effects and resulting human occupant kinematics in low speed side impact collisions. The aim of this study was to quantify the occupant response for both male and female occupants for a battery of low-speed side impacts with various impact speeds and configurations. Eight volunteers were used in a series of twenty-five staged side impact collisions with impact speeds ranging from approximately 2 km/h to 10 km/h and impact configurations to the front, middle and rear side portions of the vehicle. A NHTSA FMVSS 301 moving barrier was used as the impacting vehicle. A stiff bumper was constructed to fit the front of the barrier and was attached at a normal passenger vehicle bumper height. Occupant and vehicle responses were monitored by accelerometers and high-speed video.

Pedestrian crash kinematics have been well documented for automobile versus pedestrian collisions. However, there is not significant amount of data concerning impact of pedestrians with a high profile vehicle. A series of pedestrian crash tests using full-sized vans was performed to add to the existing database of forward projection pedestrian collisions and to compare the crash test data to existing forward throw equations. The aim of this study was to examine the trajectory behavior of the pedestrian in a forward projection impact and the effect of different friction-value surfaces when applying a pedestrian model to the data. In performing the tests, the pedestrian dummy was stabilized using an 18.2 kg tensile strength monofilament wire hanging from a cantilever beam. The impacting vans were instrumented with a triaxial accelerometer triggered at impact with the dummy. Several testing surfaces were used, ranging from dry asphalt to a skidpad with > 1/16th inch depth of water.

Pedestrian collisions are primarily a disease of urban streets and intersections, where both pedestrian and automobile traffic are in high volume. City engineers and planners are plagued with the problem of mitigating the number of pedestrian/vehicle collisions while maintaining traffic flow. In an attempt to study the problem in depth, city engineers in Helsinki, Finland placed a camera in a bus station clock tower overlooking a busy downtown intersection in February of 1991. The camera was placed at the intersection to study pedestrian and vehicle behavior at the intersection and to quantify the speeds of the respective parties. Since its installation, the camera has witnessed fifteen pedestrian/vehicle accidents. Detailed measurements of the intersection were taken for analysis of the accidents. The intersection was also calibrated with the camera in place for use of the digitizing system.

Vehicle acceleration rates and driver perception/reaction times exist in the accident reconstruction literature. However, scant data are available characterizing drivers in “real-world” situations. This study analyzes the perception/reaction times of drivers and initial acceleration rates of vehicles at signal-controlled intersections in “real-world” situations. Collection and assessment of these data facilitate evaluation of human factors characteristics and safety-related issues at these intersections. The purpose of this paper is to employ a new methodology for obtaining and analyzing “real-world” driver data. These data were analyzed to determine perception/reaction time of drivers, from signal change to initial forward movement, and vehicle acceleration rates, from a stationary position.

Analysis and reconstruction of pedestrian accidents remains a difficult task for the accident analyst. Time-distance analyses rely on currently published pedestrian walking speed data. There is a lack of real-world data in the current literature that evaluates pedestrian perception/reaction to a signal change and acceleration to a steady-state walking velocity. This study was undertaken to evaluate the behavior and gait response of pedestrians at signal-controlled intersections. Real-world observations were made at eight intersections throughout the greater Los Angeles area with a concentration on adults and elderly adults. Of particular interest was the elapsed time between the illumination of a pedestrian walk sign and gait initiation. The rate of acceleration, steady state velocity and the number of steps required to reach a steady state velocity were also measured.