Operating Plan Production in a Suburban Train Network

For a train operating company, we were responsible for all long-term and short-term schedule planning relating to a network of suburban electric trains that covered five depots, two equipment types, four terminals, and a branching structure including alternate paths, single track segments, and flat junctions.  The outputs included working timetables, vehicle diagrams (set manipulations), train crew schedules (work programs), and public timetables.  Constraints included labour agreements, train servicing needs, set storage issues, and various infrastructure related constraints.  The crewing agreements required mid-route reliefs, physical needs breaks, and daily return to home terminal.  The short term operating plans covered engineering related circumstances where special arrangements were required, such as turning sets on the main line, arranging for shuttles where line is blocked in the middle, and additional single line working if one track is closed.  Built into this work is the need to ensure conflicts do not occur en-route where two trains are scheduled to use the same track segment or interlocking at the same time, which is both infeasible and has safety implications.  Another consideration is to ensure the plan is robust, such that small perturbations to either train departure times or minor irregularities in crewing does not result in network-wide delays or train cancellations.  Aside from producing feasible pairings where every train and every set is covered by a valid crew, we were also responsible for minimizing the resource requirements for cost control and flexibility reasons.  Additionally, at that time the company was testing a new operating plan database software, so we participated in the testing and documented any anomalies we found.