The Vehicle Routing Problem

The Vehicle Routing Problem Synopsis

Theoretical research and practical applications in the ?eld of vehicle routing started in 1959 with the truck dispatching problem posed by Dantzig and Ramser [1]: ?nd the ". . . optimum routing of a ?eet of gasoline delivery trucks between a bulk terminal and a large number of service stations supplied by the terminal. " Using a method based on a linear programming formulation, their hand calculations produced a near-optimal solution with four routes to aproblemwithtwelve service stations. The authorsproclaimed:"Nopractical applications of the method have been made as yet. " In the nearly 50 years since the Dantzig and Ramser paper appeared, work in the ?eld has exploded dramatically. Today, a Google Scholar search of the words vehicle routing problem (VRP) yields more than 21,700 entries. The June 2006 issue of OR/MS Today provided a survey of 17 vendors of commercial routing software whose packages are currently capable of solving average-size problems with 1,000 stops, 50 routes, and two-hour hard-time windows in two to ten minutes [2]. In practice, vehicle routing may be the single biggest success story in operations research. For example, each day 103,500 drivers at UPS follow computer-generated routes. The drivers visit 7. 9 million customers and handle an average of 15. 6 million packages [3].