Edge assembly-based memetic algorithm for the capacitated vehicle routing problem

Vehicle routing problems are at the heart of most decision support systems for real-life distribution problems. In vehicle routing problem a set of routes must be determined at lowest total cost for a number of resources (i.e. fleet of vehicles) located at one or several points (e.g. depots, warehouses) to efficiently service a number of demand or supply points. In this paper a new memetic algorithm is suggested for the standard capacitated vehicle routing problem. The proposed algorithm combines the edge assembly (EAX) crossover with two well-known local searches and allows for infeasible solutions with respect to capacity constraint during the search. To address the constraint violation, an efficient modification algorithm is also suggested. Experimental tests on 32 standard benchmarks demonstrate that the suggested method is robust and competitive, finding the best-known solution to 28 problems and new best-known solution to 12 well-studied instances in a reasonable computing time.