The Target Visibility Projector (TarVIP) model for evaluating the nighttime visibility distances of pavement markings is described. It is capable of analyzing the conventional as well as the ultraviolet activated pavement marking visibility under UV and/or conventional headlamp illumination. The model also calculates the observed luminance caused by backscattering in foggy conditions using a series of Mie scattering functions, and determines the nighttime pavement marking visibility distance for any level of fog density defined by the user. The TarVip model was used to conduct a preliminary visibility analysis. The selected pavement marking was the Sherwin-Williams fluorescent latex paint-glass bead sample, used on a long straight level road. An increase in UV power output from the headlamp increased the detection distances of the markings. UV activated pavement markings and supplemental UV headlamps also theoretically increased the detection distances of the markings in fog. The benefits were lowest under thick fog and negligible in very dense fog. The advantage of the TarVIP model is the ability to model UV headlamps of an intensity not yet available on the market. For the covering abstract see ITRD E123380.
Abstract