Traffic management needs a good estimation of the current situation on the road network. The project investigates if data fusion of data from loop detectors and travel time measurements gives a better estimation. Research is done on the method of data fusion, on the possible improvements and on the possibilities of replacing loop detectors with travel time cameras.
In The Netherlands lanes are reduced in with if they are used as a peak-hour lane or during road works. The research in this project focusses on the traffic flow during normal circumstances, but with reductions in lane width. First, the differences between situation without and with reduction in lane width are investigated on aspects as driving behaviour, flow, speed, density and capacity. From these differences, the relation between traffic flow and the width of lanes will be estimated. Secondly, the results of the first part are used to evaluate the microsimulation model FOSIM, to which recently a module for… Read More »The relation between traffic flow and lane width
Ramp metering is an important traffic management measure the improve traffic conditions on the motorway. Ramp metering controls the flow of vehicles entering the motorway by means of a traffic light. The number of vehicles allowed to enter the motorway, or the metering rate, is determined by the ramp metering algorithm. In The Netherlands all ramp meters are equipped with the RWS ramp metering algorithm, which is a demand-capacity algorithm. This type of metering algorithm calculates the metering rate by subtracting the motorway traffic demand from the motorway capacity. For this purpose a value for the capacity is assumed by the control… Read More »Real-time capacity estimation for adaptive ramp metering
Congestion can have several causes. Whenever these causes are unpredictable, we talk of an incident. Breakdowns, accidents, loss of cargo and calamities are all examples of incidents. In the Netherlands, more then 20% of all delay hours are caused by incidents. In 1993 the initiative was taken to improve the process to deal with incidents, it was called Incident Management (IM). IM is the policy that wants to clear the road as soon as possible after the incident has occurred, especially paying attention to the traffic flow on the road, the safety on the incident-location and the safety of the rest… Read More »Traffic flow and safety during incidents
The most basic form of in-car navigation has proven to be a good application to guide travellers to their destination. These devices know the position of the traveller and lead them to their destinations. By adding traffic information to these static systems they become dynamic. Therefore it is much more complex to determine the effects on traffic. It is yet unknown what will be the consequences when more and more people start using these dynamic systems. As these dynamic systems can never tell the users exactly which traffic state they will encounter, it may have negative influence on the advices… Read More »Impact of in-car traffic information
The main idea of the project is to allocate time slots (or slices) to traffic using on-ramps of the A15 motorway to optimise dynamic network capacity and to minimise the total travel time, both on the motorway and ramps. Based on the traffic on the congested links, the problem origins can be identified in the specific time slots. Then for each problem origin, with given time slots, the adjustment in time slots can be carried out, so that these over-capacity traffic volume can be moved to the other time-slots with left-over capacity. This is actually moving over-capacity flows to those… Read More »Allocating departure time slots to optimise capacity
This graduation project studies a new control algorithm for ramp metering. Ramp metering has been introduced on the Amsterdam A10 motorway ringroad almost 20 years ago. In the near future, the remaining main on-ramps along the A10 will be equipped with ramp metering systems as well. Besides that, a new algorithm (HERO) for coordinated control of the whole ramp metering system will be implemented. However, the effects and consequences of this implementation are not clear to the Dutch motorway operator Rijkswaterstaat. Hence, the main objective of the project is to do an ex-ante study, using a simulation model, assessing the new control algorithm by comparing coordinated ramp metering with individual… Read More »Coordination of ramp metering control in a motorway network
At the end of the year 2008, the National Data Warehouse (NDW, in Dutch: Nationale Databank Wegverkeersgegevens) will become operational in the Netherlands. Its aim is to gather traffic data and to make it accessible for all stake-holding parties (road authorities, service providers, research institutes, etc.). As a consequence of this development, the process of traffic information provision changes quite drastically: more (regional) information becomes available, because of the increasing number of monitoring points, and also the quality of the data increases. This study aims to investigate the influence of the NDW coming into operation on the provision and use… Read More »Impact of National Data Ware-house on traffic information
Due to delays in the construction of new roads, measures to improve the performance of existing roads are an important aspect of transport policy in the Netherlands. Dynamic Traffic Management (DTM) measures have been implemented in the Netherlands since the 1990’s, leading to the development of a methodology for evaluating the impact of local DTM measures on traffic conditions. However, the benefits of DTM can be further increased by implementing DTM measures in a network wide, coördinated manner. Some experience with network wide DTM is allready being gained in the Netherlands and a major pilot project around Amsterdam is planned… Read More »Evaluation of network wide traffic management
Recently, a new concept called macroscopic fundamental diagram (MFD) was proposed, relating trip completion rate and the number of vehicles in a network. Some characteristics in a conservative link fundamental diagram can be observed in a MFD as well. The modeling emphasis is then shifted from microscopic prediction to macroscopic monitoring. The road operators can control the traffic situation more effectively and efficiently by applying MFD. The previous studies have investigated several factors in determining the shape of MFD. In addition, they have concluded that a large network has to be divided so that a more accurate MFD can be… Read More »Effects of DTM on the MFD for large networks