Roadway Variable Speed Limits Functional Area

Description

'Roadway Variable Speed Limits' 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 application displays the speed limits and additional information such as basic safety rules and current traffic information to drivers.

Included In

TxDOT – Dallas District Roadway Devices
TxDOT – Fort Worth District Roadway Devices

Functional Requirements

IDRequirement
01The field element shall monitor traffic and environmental conditions along the roadway.
02The field element shall autonomously calculate and set variable speed limits based on current conditions by lane.
03The field element shall receive commands from the controlling center that establish speed limits by lane.
04The field element shall display the current speed limits per lane to drivers.
05The field element shall display additional information such as basic safety rules and current traffic information to drivers.
06The field element shall collect operational status of the variable speed limit field equipment and report the operational status to the controlling center.
07The field element shall monitor and report faults to the controlling center.
08As part of speed harmonization, the field element shall display suggested speed per lane to drivers.
09As part of speed harmonization, the field element shall send suggested speed per lane to the RSE for transmittal to connected vehicles