Programmable Highway Lighting Design for a Controlled Traffic Environment

The analysis of vehicular traffic characteristics on public roads and streets indicates that in most situations the traffic volume and speed vary regularly within a 24-hour cycle. This variation establishes specific traffic flow patterns, accentuating the morning and evening peaks, as well as a slack period in the early morning hours. Based on accident distribution data within a 24-hour cycle, it appears that the degree of difficulty in performing the driving task can be related to the traffic speed and volume. It is suggested that in order to maximize the lighting impact on traffic safety, roadway illumination should be provided with suitable controls, enabling the operators to vary the lighting levels according to the traffic speed and volume.