Development of a Headlight System Performance Evaluation Tool

摘要

The report summarizes four investigations carried out to assist in thedevelopment and evaluation of a headlighting visibility model developed by NHTSA. In the first study the adaptation level of drivers was measured under various conditions. It was found that the levels calculated by the model are generally too low. In the second study data were developed on discomfort glare in order to obtain a more accurate estimate for use in the model. In the third and fourth studies, comparisons were made between the visibility of pedestrian and delineation targets as measured in the field and predicted by the model. These results suggest that the model is reasonably accurate for pedestrian targets with drivers aged 35, but significantly in error for older drivers (65+). There was also a significant discrepancy in the case of delineation targets. However, the data from the delineation studies were themselves quite inconsistent, so recommendations for corrections cannot be made with any degree of confidence.