Selective vehicle routing formulation for the order picking problem

A new view on the order picking problem is presented in which pick tours are determined using a selective vehicle routing formulation. Only corner nodes of warehouse aisles with a current demand larger than zero are considered in the network. For each of these aisles, at least one corner node should be visited while the coverage of all requested warehouse locations should be ensured. The mathematical formulation can easily be extended to include also order batching decisions