Local Municipalities_DPW - 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.
Functional Area: Roadway Environmental Monitoring
Environmental sensors, surface and sub-surface, that collect weather and road surface information. Weather conditions measured include temperature, wind, humidity, precipitation, and visibility. Sensors measure road surface temperature, moisture, icing, salinity, etc.
| ID | Requirement | Status |
|---|---|---|
| 1 | The field element shall include surface and sub-surface environmental sensors that measure road surface temperature, moisture, icing, salinity, and other measures. | Existing |
| 2 | The field element shall include environmental sensors that measure weather conditions including temperature, wind, humidity, precipitation, and visibility. | 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.
| ID | Requirement | Status |
|---|---|---|
| 1 | The field element shall include sensors that provide data and status information to other field element devices, without center control. | Existing |
| 2 | The field element shall include sensors that receive configuration data from other field element devices, without center control. | Existing |
| 3 | The field element shall include devices that provide data and status information to other field element devices without center control. | Existing |
| 4 | The field element shall include devices that receive configuration data from other field element devices, without center control. | Existing |
Functional Area: Roadway Signal Controls
Field elements including traffic signal controllers for use at signalized intersections; also supports pedestrian crossings.
| ID | Requirement | Status |
|---|---|---|
| 1 | The field element shall control traffic signals under center control. | Existing |
| 2 | The field element shall respond to pedestrian crossing requests by accommodating the pedestrian crossing. | Existing |
Functional Area: Roadway Signal Priority
Field elements that provide the capability to receive transit vehicle signal priority requests and control traffic signals accordingly.
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.
| ID | Requirement | Status |
|---|---|---|
| 2 | Under traffic and maintenance center control, the field element shall include driver information systems (such as dynamic messages signs and highway advisory radios) that advise drivers of activity around the work zone through which they are currently passing. | Existing |
Functional Area: Standard Rail Crossing
Field elements 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). Includes traditional HRI warning systems augmented with other standard traffic management devices.
| ID | Requirement | Status |
|---|---|---|
| 1 | The field element shall collect and process, traffic sensor data in the vicinity of a highway-rail intersection (HRI). | Existing |
| 7 | The field element shall close the highway-rail intersection (HRI) when a train is approaching using gates, lights/signs, barriers, and traffic control signals. | Existing |
| 8 | The field element shall support the integrated control of adjacent traffic signals to clear an area in advance of an approaching train and to manage traffic around the intersection. | Existing |