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Adrian's visibility model is a useful tool for assessing the visibility of an object at night. However, it was developed under laboratory conditions. Thus, it is necessary to determine the visibility levels which are required for detection under nighttime driving conditions. Experimental data from Olson et al were applied to the Adrian visibility model to determine visibility levels at target detection for alerted drivers. The data has been modified to account for experimental delay in the recorded detection points and a correction has been applied to assess driver expectation. Driver age, headlight beam pattern, and target reflectivity were all found to have a significant effect on visibility level at target detection. For alerted drivers, 50th-percentile threshold visibility levels between 1 and 23 were calculated. For unalerted drivers, 50th-percentile threshold visibility levels between 13 and 210 were calculated.

Collision data stored in the airbag sensing and diagnostic module (SDM) of 1996 and newer GM vehicles have become available to accident investigators through the Vetronix Crash Data Retrieval system. In this study, two experiments were performed to investigate the accuracy and sensitivity of the speed change reported by the SDM in low-speed crashes. First, two SDM-equipped vehicles were subjected to 260 staged frontal collisions with speed changes below 11 km/h. Second, the SDMs were removed from the vehicles and exposed to a wide variety of collision pulses on a linear motion sled. In all of the vehicle tests, the speed change reported by the SDM underestimated the actual speed change of the vehicle. Sled testing revealed that the shape, duration and peak acceleration of the collision pulse affected the accuracy of the SDM-reported speed change. Data from the sled tests were then used to evaluate how the SDM-reported speed change was calculated.

The purpose of this paper was to compare the damage to pickup truck bumpers produced by vehicle-to-barrier and vehicle-to-vehicle collisions of a similar severity, in order to determine whether vehicle-to-barrier tests can serve as surrogates for vehicle-to-vehicle tests in accident reconstruction. Impact tests were conducted on the front and rear bumpers of five pickup trucks. Each truck was subjected to an impact with a fixed barrier and with a passenger vehicle. All impacts resulted in pickup truck speed changes of about 8 km/h. Damage produced in the barrier and vehicle-to-vehicle collisions was similar if both collisions resulted in bumper mount damage on the pickup truck. If there was no bumper mount damage, then the bumper beam deformation depended on the shape of the impactor.

During vehicle collision testing an accurate measure of the pre- and post-impact vehicle dynamics is necessary for analytical purposes. Sensors typically used for measuring vehicle speed change in low-speed collisions include 5th wheels, high-speed video, bumper-mounted load cells, and accelerometers. The method used is often based on equipment availability, the involved vehicles, and the type of tests being performed. The purpose of this paper was to quantify the relative accuracy of these four methods in aligned low-speed rear-end collisions. Data from 73 such collisions (clustered in two groups at target vehicle speed changes of 4 and 8 km/h) showed that all four instruments yielded statistically similar results for a target vehicle speed change of about 4 km/h, and that data derived from the 5th wheel and high-speed video were different than data from the other two sensors at the 8 km/h level.

Accurate assessment of the severity of a low speed impact between two vehicles can sometimes only be accomplished through staged collisions with the actual or exemplar vehicles. However, the cost of obtaining, colliding, then repairing the vehicles often precludes this option. For this paper, two prototype moving barriers were constructed to test three different bumper assemblies separate from their vehicles. Candidate bumper assemblies were mounted to the moving barriers for low speed impact testing with a stationary barrier and three other vehicles. Forty three test series of 701 total impacts were done to compare bumper performance in moving barrier tests with their in-situ counterpart. Vehicle-to-fixed barrier, vehicle-to-vehicle, moving barrier-to-fixed barrier and moving barrier-to-vehicle tests were done using four different vehicles. The actual vehicle and moving barrier results were statistically compared.