- More Accurate Queue Length Measurement
- Increased Ramp Metering Effectiveness
- Higher Freeway Throughput, Reduced Travel Time and Reduced Crashes
- SRF Consulting Group, Inc.
- Sensys Networks Inc. (Brown Traffic Products, Inc.)
- Wavetronix LLC (Traffic Control Corporation)
Ramp Queue Detection
Several freeway on-ramps throughout the Metro area have unique geometries, such as a wide roadway section at the top of the ramp, that make it difficult for standard loop counting systems to accurately count all vehicles. Over the course of a peak period, these counting errors can add up, resulting in inaccurate queue length estimates. Because of this, Mn/DOT makes conservative estimates so that vehicles do not have to wait in the queue for over four minutes. This adversely affects mainline capacity during peak hours. The Ramp Queue Detection Project has developed and tested innovative detection systems to overcome this problem.