A discrete event simulation for the crew assignment process in North American freight railroads

This paper introduces a discrete event simulation for crew assignments and crew movements as a result of train traffic, labor rules, government regulations and optional crew schedules. The software is part of a schedule development system, FRCOS (Freight Rail Crew Optimization System), that was co-developed by Canadian National (CN) Rail and Circadian Technologies, Inc. The simulation allows verification of the impact of changes to trainflow, labor rules or government regulations on the overall operational efficiency of how crews are called to work. The system helps to evaluate changes to current crew assignments and can test new crew assignment scenarios such as crew schedules. Potential problems can be detected before the actual implementation, saving unnecessary costs. The software is also used to assess the impact of traffic changes on existing crew schedules in order to implement reactive corrections to these schedules.