Development of new railway timetabling rules for increased robustness

Due to high demand and capacity consumption, railway timetables are often sensitive to disturbances. To maintain punctual operations, it is important that timetables are robust, and methods are needed that make them robust without consuming too much capacity. In this paper, we demonstrate how a policy change in the form of new timetable planning rules can be used to achieve more robust timetables. We present the use of the rules in a real-world case from 2019, when our rules were applied for the Swedish Southern mainline. In this paper, we describe how a new policy for scheduling trains can be applied, and we discuss implications observed when going from research to practice. We also describe how the proposed rules affect train paths and runtimes. The outcome of the rules is measured in a comprehensive evaluation of the traffic performance based on empirical operational data. The results from this study show that practical knowledge is necessary when developing a policy, as well as when developing a timetabling model. Insights, given to us by experienced timetable planners, can be used to enhance optimisation models and make the models more applicable in the real world. The main contribution of this paper is to show that it is possible to increase timetable robustness with a minor policy change based on previously presented research results. Even with relatively small timetable modifications, we can learn from the operational data that the new rules had the intended effect and that overall punctuality can be increased.