Graphical Changeable Message Signs: Strategies, Impacts, and Best Practices

The Virginia Department of Transportation (VDOT) is exploring the potential of graphical changeable message signs (CMS) to improve driver comprehension and response to roadway information. While traditional CMS rely on text-only messages, advances in display technology now allow the inclusion of graphic symbols and photographic elements. However, limited research exists on how Virginia drivers interpret these graphical formats and whether they offer measurable benefits over standard text-based messages. This study will evaluate the effectiveness of graphical CMS designs in supporting driver comprehension and safe decision-making through a combination of carefully designed surveys and driving simulator experiments. An early focus of the project will be the evaluation of CMS messages developed for the Targeted Over-Height Vehicle Warning CMS system at the Hampton Roads Bridge-Tunnel (HRBT), which includes the novel feature of displaying photo of the detected over-height vehicles. This effort supports VDOT’s Request to Experiment submitted to the Federal Highway Administration (FHWA). The study will use interstate incident management as its primary case study. Results will provide VDOT with actionable guidance on the design and deployment of graphical CMS, support potential updates to statewide messaging policies, and inform future pilot projects or experimentation initiatives.

    Language

    • English

    Project

    • Status: Active
    • Funding: $374,962.00
    • Contract Numbers:

      127691

    • Sponsor Organizations:

      Virginia Transportation Research Council

      530 Edgemont Road
      Charlottesville, VA  United States  22903
    • Managing Organizations:

      Virginia Transportation Research Council

      530 Edgemont Road
      Charlottesville, VA  United States  22903
    • Project Managers:

      Lan, Chien-Lun

    • Performing Organizations:

      Virginia Transportation Research Council

      530 Edgemont Road
      Charlottesville, VA  United States  22903

      George Mason University

      School of Engineering
      CEIE Dept., MSN-6C1
      Faifax, VA  United States  22030
    • Principal Investigators:

      Lan, Chien-Lun

      Lee, Yi-Ching

    • Start Date: 20250604
    • Expected Completion Date: 20270731
    • Actual Completion Date: 0

    Subject/Index Terms

    Filing Info

    • Accession Number: 01957625
    • Record Type: Research project
    • Source Agency: Virginia Department of Transportation
    • Contract Numbers: 127691
    • Files: RIP, STATEDOT
    • Created Date: Jun 10 2025 9:49AM