A Grasp Interactive Approach to the Vehicle Routing Problem with Backhauls

Abstract

Interactive methods for vehicle routing axe appealing because they integrate the insight and experience of the user and the power and precision of heuristics in an interactive environment. Although best known results for benchmark problems are attributed to tabu search, interactive methods give results within about 3% of these solutions, whilst retaining the advantage of user control. A new interactive construction method using GRASP will be presented. The method allows vehicles to make all their deliveries, and then make pick-ups before returning to the depot. A Windows implementation allows the user to control the solution process by selecting initial outline routes of one or more deliveries followed by pick-ups. The user can also try to improve the solution, especially if it is infeasible, using interactive tools. Results will be shown for benchmark problems.