Roadway Variable Speed Limits (Equipment Packages*)

This equipment package includes the field equipment, physical overhead lane signs and associated control electronics that are used to manage and control variable speed limits systems. This equipment monitors traffic and environmental conditions along the roadway. The system can be centrally monitored and controlled by a traffic management center or it can be autonomous, calculating and setting suitable speed limits, usually by lane. This equipment located over and along the roadway displays the speed limits and additional information such as basic safety rules and current traffic information to drivers.

Included In:

Functionality:

    Functional Requirements*:
    1. The field element shall monitor traffic and environmental conditions along the roadway.
    2. The field element shall autonomously calculate and set variable speed limits based on current conditions by lane.
    3. The field element shall receive commands from the controlling center that establish speed limits by lane.
    4. The field element shall display the current speed limits per lane to drivers.
    5. The field element shall display additional information such as basic safety rules and current traffic information to drivers.
    6. The field element shall collect operational status of the variable speed limit field equipment and report the operational status to the controlling center.
    7. The field element shall monitor and report faults to the controlling center.

    Pspecs:

Inputs/Outputs (Included Architecture Flows)

Source Architecture Flow Destination
Roadway variable speed limit status this architecture flow either has been or will be addressed by ITS Standards Traffic Management
Roadway Environment environmental conditions Roadway
Traffic Management variable speed limit control this architecture flow either has been or will be addressed by ITS Standards Roadway

    - This icon indicates that the associated architecture flow either has been or will be addressed by ITS Standards. Select the architecture flow for more information on relevant standards activities.