Coordination of Ramp Metering and Variable Speed Limits

In Kamel et al. (2009), we have proposed a local ramp metering control algorithm to reduce the congestion and consequently the total time spent by the vehicles in the network. In this paper, we extend this control algorithm and propose a control approach for the coordination of ramp metering and variable speed limits. In order to evaluate the controller's efficiency and applicability, a comparison is made with the ramp metering only case and the results related to the Genetic-Fuzzy Control Application to Ramp Metering and Variable Speed Limit Control considered in Ghods et al. (2007). The macroscopic traffic model METANET and its extension for dynamic speed limits are used to present the simulation results. We conclude that the proposed coordination of ramp metering and speed limits approach improve the performance of the freeway traffic network.