Niels van Oort

RandstadRail is a new light rail system between the cities of The Hague, Rotterdam and Zoetermeer in The Netherlands. During peak hours, the frequency on some trajectories is about 24 vehicles an hour. Dealing with these high frequencies and offering travelers a high-quality product, in terms of waiting times and the probability
of getting a seat, the operator designed a three-step controlling philosophy. The first step is to prevent deviations from occurring: the infrastructure is exclusively right of way as much as possible and at intersections RandstadRail gets priority over the other traffic. RandstadRail stops at every stop and never leaves before the
scheduled time. The second step in the philosophy is dealing with deviations by planning additional time in the schedule at stops, trajectories and terminals. Small deviations can be solved in this way. The final step to get vehicles back on schedule is performed by the traffic control centre: they have a total overview of all vehicles
and they can respond to disturbances like slowing down vehicles nearby a delayed vehicle. Experiencing major disturbances rerouting and shortening of lines is possible. RandstadRail has been in operation since 2007. The actual data of the performance is used to analyze the actual effects of the control philosophy. It is shown that due to the applied measures the variability of the driving times is reduced, whereas punctuality has increased. This leads to a higher level of service, creating shorter travel times and a better distribution of passengers across the vehicles.

Read the full paper:Paper TRR 2009 Van Oort

Unreliability of public transport is a well-known problem. During the design stages of public transport, little attention is paid to operational reliability, although many design choices have a great impact on schedule adherence. During the network design, reliability should be taken into account as a design parameter. This paper
deals with line length. A new design dilemma is introduced: length of line vs. reliability. Long lines offer many direct connections, thereby saving transfers. However, the variability is often negatively related to the length of a line, leading to less schedule adherence and additional waiting time for passengers. This paper suggests taking into account both the positive and negative effects of extending or connecting line . A tool is developed to calculate the additional waiting time due to variability and transfers based on actual journey and passenger data. A case study in The Hague shows that in the case of long lines with large variability, splitting the line could result in less additional travel time because of improved reliability. This benefit compensates for the additional transfer time, provided that the transfer point is well chosen. This research shows the effect of when the transfer point is chosen at stop with many and fewer passing travelers. The latter could lead to a decrease of about 30% in additional waiting time. Splitting a long line into two lines with an overlap in the central part could even result
in more time savings. In that case, fewer travelers have to transfer.

Read the full paper:Paper TRR 2009 Van Oort