The Collision Countermeasure System (CCS) is an ITS application intended to reduce side-impact accident potential at rural, limited sight-distance intersections. It consists of activated warning signs and pavement loop detectors designed to enhance driver awareness of cross traffic. This field evaluation, comprising a four-phase observational effort (before, Acclimation, 4-month after, and 1-year after studies) assessed novelty and longer term CCS effects. Results reported herein are based on a 48-day, 109,000-vehicle data sample. In order to address CCS accident reduction potential, the study targeted 2,242 high-speed vehicles arriving at the intersection in close time proximity to cross traffic. This study also assessed the potential 'familiarization' effect, i.e., driver response to the device in its non-activated condition, and conducted a benefit/cost analysis. Vehicle behavioral measure of effectiveness (MOEs) were derived from CCS accident-avoidance objectives, i.e., specifically addressing intersection arrivals in close proximity to cross traffic. Applied MOEs were (1) drivers' CCS speed responses in the presence of cross traffic; (2) intersection approach speed reductions; and (3) projected times-to-collision (PTCs), i.e., the elapsed time to which an approaching vehicle would collide with a vehicle in its path in the absence of a timely avoidance response. Human factors (e.g., driver perception-reaction time) accident avoidance requirements determined the critical values that were used in the analysis.
Evaluation of the Prince William County Collision Countermeasure System
2001
30 pages
Report
Keine Angabe
Englisch