At present the schedules of cars and locomotives are largely manually drawn up by experienced specialists, taking from several days to several weeks to complete. As the pace of transportation planning improvement has accelerated in recent years, there has been a growing demand for the introduction of a system with automatic scheduling to improve efficiency of scheduling cars and locomotives.
When scheduling cars and locomotives for a given train operation diagram, a schedule needs to include inspections in the specified car depot/time zone within the specified days. On top of this, it is also necessary to minimize the number of train set cars, the number of inspections, and the total distance covered by deadheading trains. So far, however, no automatic scheduling has been available that can be accepted for actual operation due to severe inspection restrictions. In this study, the Railway Technical Research Institute (RTRI) has developed two kinds of algorithm that can automatically schedule cars and locomotives using the techniques of probabilistic local search and constraint logic programming.
Results of verification using actual data for two line sections showed that both algorithms could draw up schedules comparable to those made by experienced specialists in a short period of time (Fig. 1). It was also shown that the time needed for calculation depends more on the variety of trains (complexity of line sections) than on the number of trains.
Plans are underway to improve both algorithms to provide swift solutions even for complex line sections and expand their practical use through comparison checks of their applicability.