City of Toledo ITS Field Devices - ITS Roadway Equipment Functionality

Subsystem Description

'ITS Roadway Equipment' represents the ITS equipment that is distributed on and along the roadway that monitors and controls traffic and monitors and manages the roadway. This physical object 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 ramp metering systems. Lane management systems and barrier systems that control access to transportation infrastructure such as roadways, bridges and tunnels are also included. This object also provides environmental monitoring including sensors that measure road conditions, surface weather, and vehicle emissions. Work zone systems including work zone surveillance, traffic control, driver warning, and work crew safety systems are also included.

Functional Object: Roadway Advanced Rail Crossing

'Roadway Advanced Rail Crossing' manages highway traffic at highway–rail intersections (HRIs) where operational requirements demand advanced features (e.g., where rail operational speeds are greater than 80 miles per hour). The active warning systems supported by this application include positive barrier systems which preclude entrance into the intersection when the barriers are activated. This application is activated on notification by wayside interface equipment which detects, or communicates with the approaching train. In this application, additional information about the arriving train is also provided by the wayside interface equipment so that the train's direction of travel, its estimated time of arrival, and the estimated duration of closure may be derived. This enhanced information may be conveyed to the driver prior to, or in context with, warning system activation. This application also includes detection capabilities which enable it to detect an entrapped or otherwise immobilized vehicle on the grade crossing and provide an immediate notification to the wayside interface equipment and traffic management.

Functional Object: Roadway Basic Surveillance

'Roadway Basic Surveillance' monitors traffic conditions using fixed equipment such as loop detectors and CCTV cameras.

Functional Object: Roadway Data Collection

'Roadway Data Collection' collects traffic, road, and environmental conditions information for use in transportation planning, research, and other off–line applications where data quality and completeness take precedence over real–time performance. It includes the sensors, supporting roadside infrastructure, and communications equipment that collects and transfers information to a center for archival.

Functional Object: Roadway Field Device Support

'Roadway Field Device Support' monitors the operational status of field devices and detects and reports fault conditions. Consolidated operational status (device status, configuration, and fault information) are reported for resolution and repair. A local interface is provided to field personnel for local monitoring and diagnostics, supporting field maintenance, upgrade, repair, and replacement of field devices.

Functional Object: Roadway Field Management Station Operation

'Roadway Field Management Station Operation' supports direct communications between field management stations and the local field equipment under their control.

Functional Object: Roadway Mixed Use Crossing Safety

'Roadway Mixed Use Crossing Safety' is an advanced infrastructure application that detects pedestrians, cyclists, and other non–motorized users and provides active safety warnings to drivers when cross walks or other intersecting mixed use paths are occupied.

Functional Object: Roadway Multimodal Crossing Control

'Roadway Multimodal Crossing Control' monitors multimodal crossings and monitors and controls traffic control equipment in the vicinity of the crossing. Equipment controlled includes warning lights, gates, dynamic message signs, and other systems associated with multimodal crossings. It manages draw bridges and miscellaneous other crossings between highway traffic and other modes. Railroad grade crossings are covered by other functional objects.

Functional Object: Roadway Passive Monitoring

'Roadway Passive Monitoring' monitors passing vehicles for a signature that can be used to recognize the same vehicle at different points in the network and measure travel times. Depending on the implementation and the penetration rate of the technology that is monitored, other point traffic measures may also be inferred by monitoring the number of vehicles within range over time. Today this approach is implemented most commonly using a Bluetooth receiver that passively monitors Bluetooth devices on–board passing vehicles and license plate readers that record the vehicle license plate number, but any widely deployed vehicle communications technology or feature that can be passively monitored to uniquely identify a vehicle could be used.

Functional Object: Roadway Signal Control

'Roadway Signal Control' includes the field elements that monitor and control signalized intersections. It includes the traffic signal controllers, detectors, conflict monitors, signal heads, and other ancillary equipment that supports traffic signal control. It also includes field masters, and equipment that supports communications with a central monitoring and/or control system, as applicable. The communications link supports upload and download of signal timings and other parameters and reporting of current intersection status. It represents the field equipment used in all levels of traffic signal control from basic actuated systems that operate on fixed timing plans through adaptive systems. It also supports all signalized intersection configurations, including those that accommodate pedestrians. In advanced, future implementations, environmental data may be monitored and used to support dilemma zone processing and other aspects of signal control that are sensitive to local environmental conditions.

Functional Object: Roadway Signal Monitoring and Enforcement

'Roadway Signal Monitoring and Enforcement' includes the field elements that monitor vehicles entering a signalized intersection. Information is collected for vehicles illegally entering the intersection, and the signal violation is reported to the enforcement center. Control and monitoring of the signal monitoring and enforcement equipment is provided with an interface to the Traffic Management Center.

Functional Object: Roadway Standard Rail Crossing

'Roadway Standard Rail Crossing' manages highway traffic at highway–rail intersections (HRIs) where operational requirements do not dictate advanced features (e.g., where rail operational speeds are less than 80 miles per hour). Either passive (e.g., the crossbuck sign) or active warning systems (e.g., flashing lights and gates) are supported depending on the specific requirements for each intersection. These traditional HRI warning systems may also be augmented with other standard traffic management devices. The warning systems are activated on notification of an approaching train by interfaced wayside equipment. The equipment at the HRI may also be interconnected with adjacent signalized intersections so that local control can be adapted to highway–rail intersection activities. Health monitoring of the HRI equipment and interfaces is performed; detected abnormalities are reported through interfaces to the wayside interface equipment and the Traffic Management Center.

Functional Object: 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.

Functional Object: Roadway Traffic Information Dissemination

'Roadway Traffic Information Dissemination' includes field elements that provide information to drivers, including dynamic message signs and highway advisory radios.

Functional Object: Roadway Work Zone Traffic Control

'Roadway Work Zone Traffic Control' controls traffic in areas of the roadway where maintenance and construction activities are underway, monitoring and controlling traffic using field equipment such as CCTV cameras, dynamic messages signs, and gates/barriers. Work zone speeds and delays are provided to the motorist prior to the work zones.

Functional Object: Roadway Wrong Way Vehicle Detection

'Roadway Wrong Way Vehicle Detection' provides wrong way vehicle detection using traffic detectors and surveillance equipment. It provides potential wrong way vehicle notifications as well as supporting detector data and images to the center for processing and presentation to traffic operations personnel.