Control of traffic with anticipative ramp metering

When there are different routes from origin to destination in a network, the traffic divides itself over these routes. The resulting assignment is often determined by the travel times on the different routes. When control measures are implemented the travel times for some routes change, which can lead to a change in the assignment. This change in assignment can effect the performance of the whole network, but is often not automatically included in the traffic control frameworks. In this paper we develop a control method that takes these re-routing effects into account. A modelbased predictive control approach is used to determine optimal settings for traffic control measures. This control method stays optimal even when the route choice of the drivers changes. The method predicts the evolution of the traffic flows and the resulting traffic assignment, and uses this prediction to obtain the optimal control settings. To predict the traffic assignment a model is developed that, due to a low computational complexity, can be used in the controller. As an example we apply the control method on ramp metering control for a freeway network. With a case study on a small network we show the effects of the method for ramp metering, and compare it with ALINEA, an existing ramp metering control method. Van den Berg, Bellemans, De Schutter, De Moor, Hellendoorn 3