Night driving : three simulated car headlight parameters as static distance cues to oncoming vehicles

Abstract

Many motor vehicle accidents involve a driver's misperceiving the distance to another vehicle. As headlight configurations are not standardized, drivers are confronted with headlights differing in size, separation distance, and brightness. These three headlight variables were investigated in independent laboratory studies, with regards to their effect on the estimation of distance of a simulated vehicle. In each experiment, ten adult subjects estimated the distance to a simulated vehicle's headlights. "Headlights" were varied in terms of brightness, size, and separation distance between the lights. Lack of consistency in discrimination between levels of variation in size of lights, brightness, and distance between lights prevents any strong suggestions about standardization of headlights in the three variables under study. On the other hand, further research on direct distance estimation from psychological scaling of physical stiumuli is justified by the results obtained in these three experiments.