TxDOT District Traffic Management Center - Traffic Management Functionality

Subsystem Description

FWTAraffic Management Subsystem (TMS) monitors and controls traffic and the road network. It represents centers that manage a broad range of transportation facilities including freeway systems, rural and suburban highway systems, and urban and suburban traffic control systems. This subsystem communicates with the Roadway Subsystem to monitor and manage traffic flow and monitor the condition of the roadway, surrounding environmental conditions, and field equipment status. This subsystem coordinates with the Maintenance and Construction Management Subsystem to maintain the road network and coordinate and adapt to maintenance activities, closures, and detours. Incidents are detected, verified, and incident information is provided to allied agencies, drivers (through Roadway Subsystem highway advisory radio and dynamic message signs), and information service providers. This subsystem also manages traffic and transportation resources to support allied agencies in responding to, and recovering from, incidents ranging from minor traffic incidents through major disasters. When required, special traffic management strategies are implemented to support evacuation and reentry. FWTAraffic Management Subsystem supports HOV lane management and coordination, road pricing, and other demand management policies that can alleviate congestion and influence mode selection. It also manages reversible lane facilities and barrier and safeguard systems that control access to transportation infrastructure. The subsystem communicates with other Traffic Management Subsystems to coordinate traffic information and control strategies in neighboring jurisdictions. It also coordinates with rail operations to support safer and more efficient highway traffic management at highway-rail intersections. Finally, the Traffic Management Subsystem provides the capabilities to exercise control over those devices utilized for automated highway system (AHS) traffic and vehicle control.

Functional Area: Collect Traffic Surveillance

Management of traffic sensors and surveillance (CCTV) equipment, collection of current traffic conditions, and distribution of the collected information to other centers and operators.

ID Requirement Status
1 The center shall monitor, analyze, and store traffic sensor data (speed, volume, occupancy) collected from field elements under remote control of the center. Existing
2 The center shall monitor, analyze, and distribute traffic images from CCTV systems under remote control of the center. Existing
3 The center shall monitor, analyze, and store multimodal crossing and high occupancy vehicle (HOV) lane sensor data under remote control of the center. Long-term
4 The center shall distribute road network conditions data (raw or processed) based on collected and analyzed traffic sensor and surveillance data to other centers. Existing
5 The center shall respond to control data from center personnel regarding sensor and surveillance data collection, analysis, storage, and distribution. Existing
6 The center shall maintain a database of surveillance equipment and sensors and associated data (including the roadway on which they are located, the type of data collected, and the ownership of each ) Existing
7 The center shall support an interface with a map update provider, or other appropriate data sources, through which updates of digitized map data can be obtained and used as a background for traffic data. Existing

Functional Area: TMC Automated Vehicle Operations

Remotely controls Automated Highway Systems (AHS) in the field by providing AHS use and lane-changing parameters; could also be used for automated vehicle control through work zones.

ID Requirement Status
1 The center shall remotely control automated vehicle system field elements, by providing lane changing parameters, parameters for determination of vehicle suitability for particular automated lanes, and other control information required for automated highway operation. Long-term
2 The center shall maintain a log of all automated vehicle check-in and check-out transactions received from the field elements regardless of whether they are successful or not. Long-term

Functional Area: TMC Dynamic Lane Management and Shoulder Use

Remotely monitors and controls dynamically managed travel lanes, including temporary use of shoulders. It monitors conditions and determines and manages lane configuration changes. Includes intersection reconfiguration, special designated lanes, temporary shoulder use, and lane use restrictions.

ID Requirement Status
1 The center shall remotely monitor and control dynamically managed travel lanes. Long-term
2 The center shall monitor traffic conditions and demand measured per lane. Long-term
7 Based on the collected data and operator input, the center shall determine suggested and required lane control configuration changes. Long-term
8 The center shall support temporary use of shoulders as travel lanes. Long-term
9 The center shall designate lanes for use by special vehicles only, such as buses, high occupancy vehicles (HOVs), or vehicles attending a special event. Long-term
10 The center shall identify lane use restrictions, prohibiting specific types of vehicles (e.g., commercial vehicles) from specific lanes. Long-term
11 The center shall activate lane management field equipment that is used to dynamically manage specific lanes and shoulders. Long-term
12 The center shall reconfigure intersections and interchanges for compatibility with the current lane configuration. Long-term

Functional Area: TMC Environmental Monitoring

Management of environmental sensors and assimilation of collected data with other current and forecast road conditions and surface weather information from weather service providers and roadway maintenance operations.

ID Requirement Status
1 The center shall remotely control environmental sensors that measure road surface temperature, moisture, icing, salinity, and other measures. Existing
2 The center shall remotely control environmental sensors that measure weather conditions including temperature, wind, humidity, precipitation, and visibility. Existing
3 The center shall assimilate current and forecast road conditions and surface weather information using a combination of weather service provider information (such as the National Weather Service and value-added sector specific meteorological services), data from roadway maintenance operations, and environmental data collected from sensors deployed on and about the roadway. Existing
4 The center shall provide weather and road condition information to weather service providers and center personnel. Existing
5 The center shall respond to control data from center personnel regarding environmental sensor control and weather data collection and processing. Existing

Functional Area: TMC HOV Lane Management

Remotely controls HOV lane sensors, HOV lane usage signals, and ramp meters to manage use of HOV or HOT lanes; also detect HOV violators and notifies enforcement agencies.

ID Requirement Status
1 The center shall remotely control sensors to detect high-occupancy vehicle (HOV) lane usage. Existing
2 The center shall remotely control driver information systems to notify users of lane status for lanes that become HOV or High Occupancy Toll (HOT) lanes during certain times of the day on freeways. Existing
3 The center shall remotely control freeway control devices, such as ramp signals and mainline metering and other systems associated with freeway operations that control use of HOV lanes. Existing
4 The center shall collect traffic flow measures and information regarding vehicle occupancy (i.e., lane usage) in HOV lanes. Long-term
6 The center shall collect operational status for the freeway control devices associated with HOV lane control. Existing

Functional Area: TMC Incident Detection

Remotely monitors traffic sensor and surveillance systems to detect and verify incidents. Also monitors external advisory and incident reporting systems, intermodal freight depots, and border crossings for additional incident information. Identified incidents are reported to operations personnel and other centers.

ID Requirement Status
1 The center shall receive inputs from the Alerting and Advisory System concerning the possibility or occurrence of severe weather, terrorist activity, or other major emergency, including information provided by the Emergency Alert System. Existing
2 The center shall collect and store traffic flow and image data from the field equipment to detect and verify incidents. Existing
7 The center shall provide video and traffic sensor control commands to the field equipment to detect and verify incidents. Existing

Functional Area: TMC Incident Dispatch Coordination/Communication

Formulates an incident response that takes into account the incident potential, incident impacts, and/or resources required for incident management. Facilitates the dispatch of emergency response and service vehicles and coordinates the response with cooperating agencies.

ID Requirement Status
4 The center shall exchange incident information with emergency management centers, maintenance and construction centers, transit centers, information service providers, and the media including description, location, traffic impact, status, expected duration, and response information. Existing
5 The center shall share resources with allied agency centers to implement special traffic control measures, assist in clean up, verify an incident, etc. This may also involve coordination with maintenance centers. Existing

Functional Area: TMC Probe Information Collection

Collects, assimilates, and disseminates vehicle probe data collected from roadside beacons and centers controlling transit vehicles, emergency vehicles, toll collection points, and route-guided vehicles.

ID Requirement Status
1 The center shall collect traffic probe data from vehicles via roadside field equipment. Medium-term
5 The center shall assimilate current and forecast traffic conditions based on collected probe data and distribute to other centers for dissemination to travelers. Medium-term

Functional Area: TMC Regional Traffic Management

Coordination between traffic management centers in order to share traffic information between centers as well as control of traffic management field equipment. This may be used during incidents and special events and during day-to-day operations.

ID Requirement Status
1 The center shall exchange traffic information with other traffic management centers including incident information, congestion data, traffic data, signal timing plans, and real-time signal control information. Existing
2 The center shall exchange traffic control information with other traffic management centers to support remote monitoring and control of traffic management devices (e.g. signs, sensors, signals, cameras, etc.). Existing

Functional Area: TMC Signal Control

Remotely controls traffic signal controllers to implement traffic management strategies at signalized intersections based on traffic conditions, incidents, emergency vehicle preemptions, pedestrian crossings, etc.

ID Requirement Status
1 The center shall remotely control traffic signal controllers. Existing
3 The center shall collect traffic signal controller operational status and compare against the control information sent by the center. Existing
4 The center shall collect traffic signal controller fault data from the field. Existing
5 The center shall manage (define, store and modify) control plans to coordinate signalized intersections, to be engaged at the direction of center personnel or according to a daily schedule. Existing
6 The center shall implement control plans to coordinate signalized intersections based on data from sensors. Existing
7 The center shall manage boundaries of the control sections used within the signal system. Existing
8 The center shall maintain traffic signal coordination including synchronizing clocks throughout the system. Existing

Functional Area: TMC Traffic Information Dissemination

Controls dissemination of traffic-related data to other centers, the media, and travelers via the driver information systems (DMS, HAR) that it operates.

ID Requirement Status
1 The center shall remotely control dynamic messages signs for dissemination of traffic and other information to drivers. Existing
3 The center shall collect operational status for the driver information systems equipment (DMS, HAR, etc.). Existing
4 The center shall collect fault data for the driver information systems equipment (DMS, HAR, etc.) for repair. Existing
5 The center shall retrieve locally stored traffic information, including current and forecasted traffic information, road and weather conditions, traffic incident information, information on diversions and alternate routes, closures, and special traffic restrictions (lane/shoulder use, weight restrictions, width restrictions, HOV requirements), and the definition of the road network itself. Existing
6 The center shall distribute traffic data to maintenance and construction centers, transit centers, emergency management centers, and traveler information providers. Existing
8 The center shall provide the capability for center personnel to control the nature of the data that is available to non-traffic operations centers and the media. Existing

Functional Area: TMC Traffic Metering

Remotely controls ramp meters, interchange connector meters, and mainline meters, covering all types of metering as well as management of bypass lanes.

ID Requirement Status
1 The center shall remotely control systems to manage use of the freeways, including ramp, interchange, and mainline metering. Long-term
4 The center shall implement control strategies, under control of center personnel, on some or all of the freeway network devices (e.g. ramp meters, interchange meters, and mainline meters), based on data from sensors monitoring traffic conditions upstream, downstream, and queue data on the approaches to the meters. Long-term

Functional Area: TMC Transportation Operations Data Collection

Collects real-time information on the state of the regional transportation system for operational use by the center. It establishes communications with a regional repository, requests or subscribes to information relevant to the center, and distributes the received information for use.

ID Requirement Status
1 The center shall collect real-time information on the state of the regional transportation system including current traffic and road conditions, weather conditions, special event and incident information. Medium-term
2 The center shall support the capability for the system operator to monitor and control the information collection service. Medium-term

Functional Area: TMC Variable Speed Limits

Remotely monitors and controls variable speed limits systems, including equipment that monitors current traffic and environmental conditions, determines the current speed limits by lane, and displays the speed limits and additional information to drivers.

ID Requirement Status
1 The center shall monitor data on traffic and environmental conditions collected from sensors along the roadway. Long-term
2 Based on the measured data, the center shall calculate and set suitable speed limits by lane. Long-term
3 The center shall control field equipment that posts the current speed limits and displays additional information such as basic safety rules and current traffic information to drivers. Long-term
4 The center shall monitor the operational status of the variable speed limit equipment, including fault reports. Long-term
5 The center shall provide center personnel current system status and respond to control data from center personnel regarding variable speed limits and Long-term

Functional Area: TMC Work Zone Traffic Management

Coordination with maintenance systems using work zone images and traveler information systems (such as DMS), and distribution of work plans so that work zones are established that have minimum traffic impact.

ID Requirement Status
1 The center shall receive work zone images from a maintenance center. Medium-term
2 The center shall analyze work zone images for indications of a possible incident. Medium-term
3 The center shall remotely control driver information systems (such as dynamic messages signs, highway advisory radios) to advise drivers of activity around a work zone. Medium-term
4 The center shall collect operational status for the driver information systems equipment in work zones. Medium-term
5 The center shall collect fault data for the driver information systems equipment in work zones for repair. Medium-term
6 The center shall receive proposed maintenance and construction work plans, analyze the activity as a possible incident, and provide work plan feedback to the sending center. Medium-term

Functional Area: Traffic Data Collection

Collection and storage of traffic management data. For use by operations personnel or data archives in the region.

ID Requirement Status
1 The center shall collect traffic management data such as operational data, event logs, etc. Medium-term
2 The center shall assign quality control metrics and meta-data to be stored along with the data. Meta-data may include attributes that describe the source and quality of the data and the conditions surrounding the collection of the data. Medium-term
3 The center shall receive and respond to requests from ITS Archives for either a catalog of the traffic data or for the data itself. Medium-term
4 The center shall be able to produce sample products of the data available. Medium-term