CLR Analytics


TransModeler Plugins

The plugin utilizes the API functions from TransModeler to perform the following functions:

  • Detector data aggregation
  • Ramp metering control based on the following logic:
    • SATMS (demand capacity logic), deployed in Caltrans District 7 (Los Angeles County) and 12 (Orange County)
    • SDRMS (volume control and occupancy control logic), deployed in Caltrans District 11 (San Diego), District 8 (Riverside and San Bernadino), District 3 (Sacramento)
    • ALINEA

Development of an ALINEA based coordinated ramp metering plugin in TransModeler (10/14/2011)

We are proud to announce the news that we are working with Cambridge Systematics, Caltrans District 11 and SANDAG to develop an ALINEA based coordinated ramp metering algorithm and its plugin in TransModeler. The algorithm to be implemented is based on a modified ALINEA algorithm originally proposed by Caltrans District 11, which also requires the algorithm to work with the existing SDRMS ramp metering system.

Based on our extensive knowledge of ramp metering control, we at CLR Analytics have further refined the algorithm based on multiple literatures about the ALINEA algorithm. The development is on-going and the ultimate goal is to allow the plugin to provide users with flexibility in setting up coordinated ramp metering control based on ALINEA adjustments. There will be discussion among Cambridge Systematics, Caltrans District 11, SANDAG, and USDOT before finalizing the design of the algorithm. Then, the algorithm will be implemented as a plugin under TransModeler. The plugin will be used to test how the improved algorithm can help decrese the traffic congestion for the I-15 corridor ICM project in San Diego.

As the consultant that reverse-engineered the SDRMS ramp metering algorithm used in San Diego, Sacramento, Riverside-San Bernardino areas, we have implemented the algorithm under TransModeler, a traffic simulator developed by Caliper Corp in Year 2009. 

ALINEA is a feedback ramp metering control logic proposed by Prof. Markos Papageorgiou in 1990s. 
Client: USDOT, SANDAG, Caltrans District 11
Prime Contractor: Cambridge Systematics
Project Time Period: Oct 2011 – Nov 2011