No abstract

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.

The Amsterdam Practical Trial (APT) is a multiyear program initiated by the Dutch Ministry of Transport and the Environment and is carried out in close cooperation by Rijkswaterstaat, the City of Amsterdam, the Province of North Holland, and the Amsterdam Metropolitan Region. The APT aims to integrate innovative roadside and in-car developments networkwide. After the proof of concept was finished in 2009, two parallel tracks started in the Amsterdam region: the roadside track (aiming at an innovative, automated working system with ramp metering and traffic lights) and the in-car track (aiming at individualized travel and traffic information in the car for commuter traffic and for large-event traffic). This paper aims specifically at the innovative APT roadside system. Development of this system began in 2012, with the system becoming operational in April 2014. After all technical and functional tests were completed, the system parameters were tuned and finalized the implementation phase. Starting April 14, 11 weeks were taken to collect the data for the ex post assessment. In doing so, the authors have used an alternating assessment design, implemented by switching the system on and off every week so that a fair comparison could be made. From the collected data, it could be concluded that while the system caused additional delays on the urban network and ramps, the throughput on the freeway arterial was improved. Detailed analysis of the data showed the system performed as expected and which improvements can be made to further increase its effectiveness. These optimizations are discussed, as are the expected effects of implementing them in the system. How they are operationalized in Phase 2 of this innovative project will also be discussed.