Railway timetable optimization considering robustness and overtakings

This paper focuses on optimizing the robustness of a timetable with multiple train lines of different frequencies, where overtakings are also taken into account. An optimization model is considered of a cyclic railway timetable problem where dwell times and running times are variable and overtaking is allowed for relevant stations and each line. Based on the Periodic Event Scheduling Problem, train journey time, robustness and the number of dwell time stretches (which decides whether a train can have overtakings) are proposed as objectives, with corresponding constraints included in the model. This approach is studied in a small network with six stations and proved to be efficient. Six model variants from a different combination of objectives and constraints are compared on robustness, for which a number of robustness indicators are defined.