The potential benefits offered by high-intensity discharge (HID) sources for vehicle headlamps have raised new issues in the design of headlamp beam patterns. The primary purpose of the present study is to address some of those issues by quantifying the effects of one major aspect of headlamp beam patterns--foreground light--on visual performance. We measured the seeing distance to a dark-clad pedestrian at night on a two-lane road as a function of observer age, foreground luminance, and pavement condition (dry/wet). Observers sat in the driver's seat of a stationary vehicle positioned on the road while a pedestrian walked either toward or away from the vehicle. The observer indicated when the pedestrian just became visible or invisible, depending on the direction of movement. Two major limitations apply to the interpretation of the effects observed in this study. First, the effects of glare from opposing headlamps were not measured. Second, only the effects of pavement wetness itself were measured, not the effects of active precipitation.
Effects of Foreground Illumination, Wet Pavement, and Driver Age on Pedestrian Detection Distance
1995
32 pages
Report
Keine Angabe
Englisch
Transportation Safety , Road Transportation , Headlamp design , Pedestrian visibility , Driver perception , Visual perception , Night visibility , Pedestrian safety , Visibility , Driver performance , Driver age , Wet road conditions , Illumination , Headlamp tests , High intensity lighting , Foreground light
Adaptive learning of multi-subspace for foreground detection under illumination changes
British Library Online Contents | 2011
|