Automatic Identification of Route Conflict Occurrences and Their Consequences

This paper describes how knowing the source of delays is crucial information to railway infrastructure managers and train operators but assigning a given delay to its causes is very difficult. Actual delays at stations are monitored online using train describer systems and timetable databases, but it is unknown whether for instance a delay has been caused by a slow running train or by a route conflict where a driver had to slow down due to a restricted signal. In particular, delays due to route conflicts are hard to recognize afterwards, although their identification is crucial to assess and optimize the quality of infrastructure capacity allocation. This paper presents the software tool TNV-Conflict that identifies automatically all signaled route conflicts including the critical sections and conflicting trains. The developed tool can be used offline using train describer logfiles containing chronological infrastructure and train description messages. The object-oriented approach already anticipates an online implementation based on real-time messages. The resulting information is used to analyze the number of route conflicts and their effect on capacity consumption and punctuality, to assign knock-on delays to conflicting trains in a non-discriminatory way, and to identify structural route conflicts corresponding to timetable flaws (e.g. infeasible minimum headways, late trains due to preceding bottlenecks, and early trains due to excessive running time supplements). TNV-Conflict provides essential information to improve capacity allocation and construct reliable train paths. An example application on a railway corridor in the Netherlands illustrates the potential of the tool.