Intelligent Transportation System Field Demonstration

Abstract

Contending with recurrent congestion on commuting corridors has long been a challenging and pressing issue for responsible highway agencies. However, effective strategies to mitigate the congestion level and the accompanying safety issues on those highway segments remain to be developed. In response to such needs, this study presents an innovative system that integrates variable speed control and travel time information for alleviating day-to-day recurrent congestion on a highway corridor. The system presented in this study includes a set of algorithms for setting variable speeds for different highway segments based on traffic conditions detected from roadway sensors and a well-calibrated license-plate-recognition system for displaying the estimated travel time. Field experiments of the proposed system on MD-100 for 8 weeks showed that with proper speed control in real time, the congested highway segment can achieve a higher throughput, a stable traffic condition, and a shorter travel time.

Safety-Oriented Speed Guidance of Urban Expressway under Model Predictive Control

“…Bertini evaluated the VSL strategy used at Autobahn 5 in Germany using the empirical data, the result showed that the effectiveness of VSL strategy in reducing congestion at bottlenecks was significant [14]. On the other hand, some VSL experiment had been carried out which concluded that VSL experiment had a significant effect in reducing speed variation and the number of shockwaves [15][16][17][18][19]. Representative researches of Hegyi have shown that the traffic shock wave can be better smoothed by VSL under MPC [20].…”