Simultaneous cooperation of Refrigerated Ground Vehicle (RGV) and Unmanned Aerial Vehicle (UAV) for rapid delivery with perishable food

Abstract

With the growth of e-commerce, various types of last-mile delivery services have emerged to meet customer needs. Among the most notable of these are “rapid delivery” and “perishable food delivery” services. Owing to their advantages, the use of unmanned aerial vehicles (UAVs), which are both fast and inexpensive, has received considerable interest for rapid delivery. However, because of the inherent limitations of UAVs, they are used in conjunction with other ground vehicles. In contrast, maintaining freshness during delivery of perishable food is crucial for customer satisfaction and hygiene. Consequently, the cooperative operation of refrigerated ground vehicles (RGVs) with UAVs is necessary for rapid and fresh delivery services. RGVs can focus on the delivery of perishable foods and large-sized general products in such an operation, whereas UAVs can focus on small-sized general goods. In this study, the cooperative operation of RGVs and UAVs was investigated for the rapid delivery of perishable food. Mixed integer linear programming (MILP) was developed to derive optimal delivery schedules for RGVs and UAVs with the objective of minimizing the maximum service completion time of delivery vehicles. Additionally, an RGV-UAV route generating algorithm (R-U RGA) was presented to efficiently derive optimal, near-optimal, or qualified vehicle schedules when the MILP fails to derive optimal schedules in a reasonable time. The validity of the proposed MILP model was verified through a case study. The usefulness of the R-U RGA was confirmed through numerical experiments conducted on instances of various sizes. Additionally, numerical tests were performed to compare the benefits of the RGV-only delivery system and the proposed cooperative delivery system. These tests conducted in terms of economic, environmental, and service factors; they quantitatively elucidate the tradeoffs between the two systems.