Enhancing the Messages Displayed on Dynamic Message Signs

A human factors study was carried out to help enhance ways tocommunicate with highway motorists through dynamic message signs (DMS).Overhead mounted DMSs have been increasingly used by highway authorities inthe United States to present real-time traffic information and travel advice tomotorists. It is critical to post sign messages that can be quickly and clearlyunderstood by motorists, especially in high-volume traffic and construction/repairzones. Properly worded and formatted sign messages could spell the differencebetween comprehension and confusion. Message display factors investigated inthe study include display effects, color schemes, wording, and formats. Twoapproaches were employed in this study. First, a questionnaire survey wasdeveloped to collect motorists’ preferences regarding various message displayfactors. Second, a series of lab driving simulation experiments were set up toassess the effects of these factors and their interactions on motorists’comprehension of DMS messages. Study results suggested that static, one-framedmessages with more specific wording and no abbreviations were preferred.Amber or green or a green-amber combination were the most favored colors.Younger subjects took less response time to the DMS stimuli with higheraccuracy than older subjects. There were no significant gender differences