One of the more recent technologies available for improving road delineation are solar powered LED illuminated pavement markers that activate in response to environmental conditions such as rain, ice, or fading light. Self-illuminated pavement markers offer certain advantages over conventional retroreflective markers, the most obvious being their visibility. Conventional retroreflective pavement markers function by returning light in the direction from which they are illuminated. To a driver, conventional retroreflective markers appear bright only when headlights are shining directly onto them. As such, there are limits to the extent to which effective delineation around a curve can be maintained using conventional retroreflective markers. Internally-illuminated markers are designed to provide drivers with consistent light output from a wide range of viewing angles, thus giving a clear indication of road curvature throughout a curve. This Note concerns an assessment of the performance of the self-activated pavement markers included laboratory tests which sought to determine the consistency of the markers' on-off thresholds in response to fading light, fog, and low temperatures. (a).
Samenvatting