PTC Traffic Operations Center (PTC Ops Center) - Roadway Functionality

Subsystem Description

The Roadway Subsystem (RS) includes the equipment distributed on and along the roadway that monitors and controls traffic and monitors and manages the roadway itself. Equipment includes traffic detectors, environmental sensors, traffic signals, highway advisory radios, dynamic message signs, CCTV cameras and video image processing systems, grade crossing warning systems, and freeway ramp metering systems. HOV lane management, reversible lane management functions, and barrier systems that control access to transportation infrastructure such as roadways, bridges and tunnels are also supported. This subsystem also provides the capability for environmental monitoring including sensors that measure road conditions, surface weather, and vehicle emissions. In adverse conditions, automated systems can be used to apply anti-icing materials, disperse fog, etc. Work zone systems including work zone surveillance, traffic control, driver warning, and work crew safety systems are also included. To enhance security, safeguard systems such as blast shields, exhaust systems and other automated and remotely controlled systems to protect transportation infrastructure is also provided. In advanced implementations, this subsystem supports automated vehicle safety systems by safely controlling access to and egress from an Automated Highway System through monitoring of, and communications with, AHS vehicles. Intersection collision avoidance functions are provided by determining the probability of a collision in the intersection and sending appropriate warnings and/or control actions to the approaching vehicles.

Functional Area: Roadway Basic Surveillance

Field elements that monitor traffic conditions using loop detectors and CCTV cameras.

IDRequirementStatus
1The field element shall collect, process, digitize, and send traffic sensor data (speed, volume, and occupancy) to the center for further analysis and storage, under center control.Future
2The field element shall collect, process, and send traffic images to the center for further analysis and distribution.Existing
4The field element shall return sensor and CCTV system operational status to the controlling center.Existing

Functional Area: Roadway Data Collection

Field elements to collect traffic, road, and environmental conditions information for use in transportation planning, research, and other off-line applications. Includes the sensors, supporting roadside infrastructure, and communications equipment.

IDRequirementStatus
1The field element shall collect traffic, road, and environmental conditions information.Existing
2The field element shall include the sensors and supporting roadside devices that sense, collect, and send traffic, road, and environmental conditions information to a center for archival.Existing

Functional Area: Roadway Equipment Coordination

Field elements that control and send data to other field elements (such as environmental sensors that send data to a DMS or coordination between traffic controllers on adjacent intersections), without center control.

Functional Area: Roadway Incident Detection

Field elements that monitor traffic conditions to identify incidents. It includes traffic detectors that collect traffic flow information and identify unusual traffic conditions and advanced CCTV cameras with built-in incident detection algorithms.

IDRequirementStatus
1The field element shall collect, process, and send traffic images to the center for further analysis and distribution.Existing
2The field element shall remotely process video data and provide an indication of potential incidents to the traffic management center.Existing
3The field element's video devices shall be remotely controlled by a traffic management center.Existing
4The field element shall provide operational status and fault data for the incident detection devices to the traffic management center.Existing

Functional Area: Roadway Probe Data Communications

Field elements that collect probe data from vehicles using short range communications.

IDRequirementStatus
1The field element shall communicate with passing vehicles for traffic data link time calculations and send collected data to the controlling center; identification will be removed to ensure anonymity.Future
2The field element shall communicate with on-board equipment on passing vehicles to collect current vehicle position, speed, and heading and a record of previous events (e.g., starts and stops, link travel times) that can be used to determine current traffic conditions.Future

Functional Area: Roadway Work Zone Traffic Control

Field elements in maintenance and construction areas including CCTV cameras, driver information systems (such as DMS), and gates/barriers that monitor and control traffic and provide information directly to drivers in affected areas.

IDRequirementStatus
1The field element shall collect, process, and send work zone images to the center for further analysis and distribution, under center control.Future