A disjunctive program formulation to generate regular public transit timetables adhering to prioritized planning requirements

Timetable regularity is an important measure for service quality in high frequency public transit systems, assuring an evenly distributed passenger load as well as improving product attractiveness and appreciation. However, to be feasible during daily operation a timetable may also have to adhere to other planning requirements, e.g. limitations to permitted departure times to better coordinate with other service providers like schools or long-distance transportation networks. In this paper a disjunctive program formulation is proposed to generate regular timetables adhering to planning requirements. The modeled requirements not only allow for the consideration of feasibility constraints from daily operations, but also for the consideration of simultaneous departures for transfer connect ions, an objective traditionally opposed to regularity. To show its applicability the approach is applied to two models of artificial transit networks as well as to a model of the bus network of Cologne, Germany. The results show that the proposed formulation can be used to generate timetables for network instances of realistic size in acceptable time using CPLEX. For networks consisting of multiple connected components it is shown that a divide and conquer approach can significantly reduce run times.