ODOT Variable Speed Limit Signs
Status
Existing
Description
Variable Speed Limit (VSL) signs are an ITS element related to Ohio's Active Traffic and Demand Management (ATDM) program that aims to increase travel time reliability on Ohio DOT roadways in major metro areas. VSL signs in the field communicate centrally with the Ohio DOT ATMS, and reduced speeds would be implemented either by TMC operators or can be automated based on the level of traffic detected by nearby Ohio DOT Vehicle Detection Devices.
Stakeholders
Physical Objects
Functional Objects
| Functional Object | Description | User Defined |
|---|
| Roadway Time Management | 'Roadway Time Management' provides foundational time keeping functionality that supports an accurate, synchronized time reference in ITS field equipment. It receives accurate time information from an external source and maintains a local time reference using an internal clock in between time synchronizations. | False |
|---|
| Roadway Variable Speed Limits | '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. | False |
|---|
Physical Standards
| SDO | Document # | Title | User Defined |
|---|
| ITE | ITE ITS Cabinet | ITS Standard Specification for Roadside Cabinets | False |
|---|
| NEMA | NEMA TS 8 | Cyber and Physical Security for Intelligent Transportation Systems (ITS) | False |
|---|
Interfaces To
(View Context Diagram)