Heuristic approaches for the Fleet Size and Mix Vehicle Routing Problem with Time Windows

The Fleet Size and Mix Vehicle Routing Problem with Time Windows(VRPTW) is the problem of determining, at the same time, the composition and the routing of a fleet of heterogeneous vehicles aimed to serve a given set of customers. The routing problem requires to design a set of minimum cost routes originating and terminating at a central depot and serving customers with known demands, within given time windows. This paper develops a constructive insertion heuristic and a metaheuristic algorithm for VRPTW. Extensive computational experiments on benchmark instances show that the proposed method is robust and efficient, and outperforms the previously published results