A VNS Approach for Batch Sequencing and Route Planning in Manual Picking System with Time Windows

摘要

In this paper an order picking and route planning problem is studied. The main objective is to minimize the number of pickers involved in collecting the order pool and the total distance covered by the pickers. Since the problem under study is NP-hard, a variable neighborhood search (VNS) is proposed as a heuristic solution approach. Neighborhood is changed according to VNS scheme employing four tailored structures. Finally, computational tests demonstrate that the proposed VNS algorithm can find good quality solutions for all practical problems examined. The objective values, regarding both the number of pickers employed and the total distance covered by them, are better than the results of genetic algorithm and close to the ones obtained by CPLEX Solver, if it was able to provide a feasible solution.