An ILS-based algorithm to solve a large-scale real heterogeneous fleet VRP with multi-trips and docking constraints

Distribution planning is crucial for most companies since goods are rarely produced and consumed at the same place. Distribution costs, in addition, can be an important component of the final cost of the products. In this paper, we study a VRP variant inspired on a real case of a large distribution company. In particular, we consider a VRP with a heterogeneous fleet of vehicles that are allowed to perform multiple trips. The problem also includes docking constraints in which some vehicles are unable to serve some particular customers, and a realistic objective function with vehicles’ fixed and distance-based cost and a cost per customer visited. We design a trajectory search heuristic called GILS-VND that combines Iterated Local Search ∗ orresponding author Email addresses: [email protected] (V.N. Coelho), [email protected] (A. Grasas), [email protected] (H. Ramalhinho), [email protected] (I.M. Coelho), [email protected] (M.J.F. Souza), [email protected] (R.C. Cruz) Preprint submitted to European Journal of Operational Research September 28, 2015