Iterated Local Search for a Vehicle Routing Problem with Synchronization Constraints

Abstract : This paper deals with vehicle routing problem (VRP) with synchronization constraints. This problem consists in determining a least-cost set of routes to serve customers who may require several synchronized visits. The main contribution of the paper is: 1) it presents a definition and a classification of different types of synchronization constraints considered in the VRP literature; 2) it describes a variant of vehicle routing problem with synchronization constraints which is formulated as a mixed integer programming model; 3) finally, it provides a constructive heuristics and an iterated local search metaheuristic to solve the considered problem. The performance of the proposed approaches is evaluated on small and medium sized instances.