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Praktijkproef Amsterdam (Field Operational Test Integrated Network Management Amsterdam) is a project focused on the design and implementation of an innovative system for the coordinated deployment of traffic management measures in the regional network around the city of Amsterdam, Netherlands. On the basis of the generic functional architecture described in previous publications, monitoring and control functions were specified, implemented, tested, and tuned, both in a model environment and in practice. The focus here is on the controller design, which adapts and generalizes the master–slave structure used in the well-known HERO algorithm. It is shown how the principles are applied to use the urban arterials as storage locations for freeway metered traffic as well as to solve problems occurring on the urban arterials themselves—for example, in the case of spillback or gridlock. The key control principles are explained and the resulting feedback controller is analyzed to show how to choose its parameters to ensure stability and minimize the time needed to achieve the target value. To this end, a new methodology is proposed to analyze the dynamics of the controller in relation to the control parameters for different controller designs. Finally, the implementation of the system is discussed, and preliminary tuning and evaluation results from the field tests are provided.

When applying dynamic route guidance to improve the network performance, it is important to balance the interests of the road authorities and the road users. In this paper we will illustrate how bounded rationality and indifference bands can be taken into account in dynamic route guidance to improve the network performance while respecting the interests of road users. The paper elaborates on empirical findings reported in literature to propose a suitable interpretation and utilization of the indifference bands in a control approach. By means of a service level-oriented route guidance control approach we evaluated the potential gain in network performance of different absolute indifference bands. Results from a simulation test case show a reduction in total travel time of 5% compared to user equilibrium, in case of an indifference band of 4 minutes for a trip of approximately 22 minutes. The improvement in network performance increases with an increasing indifferent band, up to 14% in case of an indifference band of 10 minutes.

In this paper, a coordinated ramp-metering approach is proposed; the approach is based on the synchronization of the time it takes for an on-ramp to run out of space. The time that congestion and the associated capacity drop can be prevented at a freeway bottleneck by means of ramp metering depends on the available ramp space for temporarily storing the vehicles. For a single on-ramp, the available space and thus the metering time at the bottleneck are often limited. By means of coordination, upstream storage space can be used to prevent a breakdown for a longer period of time. To accomplish that aim, upstream ramps need to reduce their inflow into the mainstream with respect to their own metering task. The extent to which upstream inflow reductions are effectively used to extend the metering time at the bottleneck is determined by the order and timing at which the coordinated ramps run out of space. The proposed approach aims at always saturating the more upstream-located ramps before more downstream-located ones; that is, the ramps run out of space in the downstream direction to make sure that all realized assistance is used by the ramp that is metering at the bottleneck. By means of a simulation test case, the functioning of the algorithm is demonstrated and compared with a no-control scenario, local ramp metering, and an alternative coordination algorithm that aims at filling the ramps equally. Both coordination approaches strongly improve the network performance with respect to local ramp metering, but the proposed coordination approach is able to postpone the breakdown for a longer period of time.

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