Abstract

Many remote stretches of highway are subject to multi-vehicle accidents resulting from sudden reductions in visibility caused by wind-blown snow or dust. Current approaches for alerting motorists use overhead signs that are manually activated by highway department personnel, based on eyewitness reports from drivers delivered in person or transmitted over CB radio. While this method has resulted in some reduction in the accident rate, it is unreliable and subject to reporting delays. A better technique would be to remotely detect changes in visibility onsite just before they become hazardous and activate warning signs automatically. Relatively inexpensive lidar systems can provide the required measurements.

© 1995 Optical Society of America