Deutsche Bahn Schedules Train Rotations Using Hypergraph Optimization

Deutsche Bahn (DB) operates a large fleet of rolling stock (locomotives, wagons, and train sets) that must be combined into trains to perform rotations. This composition is special characteristic railway operations distinguishes rotation planning from the vehicle scheduling problems prevalent in other industries. DB models compositions using hyperarcs. The resulting hypergraph are addressed novel coarse-to-fine method implements hierarchical column generation over three levels detail. algorithm mathematical core DB’s employment optimization (FEO) system for planning. FEO’s impact within departments has been revolutionary. used it support company’s procurements its newest high-speed passenger intermodal cargo locomotive crossborder operations. FEO key successful tendering regional transport construction site management daily appreciate high-quality results, ability reoptimize (quickly), ease use. Both employees customers benefit increased regularity attributes annual savings 74 million euro, an reduction 34,000 tons CO 2 emissions, elimination 600 coupling implementation FEO.