IRIS
Intelligent Roadway Information System
Ramp Meters
Select View ➔ Ramp Meters
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A ramp meter is a traffic signal at an on-ramp which controls the rate of vehicles entering a freeway. Typically, one vehicle is permitted to enter for each green indication displayed on the signal.
The following operations can be performed on a ramp meter:
- Activating and deactivating meter
- Adjusting meter release rate
- Querying meter status
- Querying green counts
- Synchronizing clock
- Configuring time-of-day operation
Metering Strategies
Each ramp meter can be assigned a metering strategy, or algorithm. There are currently two metering strategies available — simple and density adaptive.
Simple metering runs the ramp meter at a fixed release rate. This rate is the target rate for the period (AM or PM).