The Vehicle Routing Problem with Simultaneous Pickup and Delivery and Parcel Lockers

Abstract

Customers’ expectations of timely and accurate delivery and pickup of online purchases pose a new challenge to last-mile delivery. When the goods sent to customers are not received, they must be returned to the warehouse. This situation provides a high additional cost. Parcel locker systems and convenience stores have been launched to solve this problem and serve as pickup and payment stations. This research investigates a new last-mile distribution problem in the augmented system with three service modes: home delivery and pickup, parcel locker delivery and pickup, and home or parcel locker delivery and pickup. Previously, the simultaneous delivery and pickup problem with time windows (SDPPTW) only considered delivery and pickup to customers. The new problem proposed in this research addresses additional locker pickup and delivery options. The proposed problem is called the vehicle routing problem with simultaneous pickup and delivery and parcel lockers (VRPSPDPL). This research formulated a new mathematical model and developed two simulated annealing (SA) algorithms to solve the problem. The goal is to minimize the total traveling cost. Since there are no existing benchmark instances for the problem, we generate new instances based on SDPPTW benchmark instances. The experimental results show that the proposed algorithms are effective and efficient in solving VRPSPDPL.