## 1 Introduction
### Related Surveys  
In recent years, numerous efforts have been made to address the existing drone-based logistics systems, as summarized in Table 1. Most existing reviews have emphasized the different aspects of drone-based delivery systems to provide a holistic review. Next, we discuss and summarize the reviews that cover the current research progress on drone routing problem for designing drone-based logistics systems. In [4], the authors investigated the major issues faced while designing and modeling the drone-based delivery systems and their potential solutions. In addition, they provided the current scenario of parcel delivery using drones with respect to the existing literature. However, this study presents a general overview of the existing literature and does not discuss the major design issues in sufficient detail. In [21], the authors discussed the existing techniques for drone-based delivery from an energy management perspective. The authors discussed several ways to provide energy to the drone during the delivery mission such as battery swapping, utilization of laser beam based charging, and tethered UAVs. In [22], the authors emphasized the operational planning aspect of the drone-based delivery systems. They presented a comprehensive review with a unique classification of the existing logistics systems. This classification was made in terms of various operational factors such as supporting vehicles, number of depots, and touchpoints. Although their presented classification is unique, their study focuses only on the operational aspects and ignores other major aspects of drone-based delivery such as energy management techniques, routing techniques, and security issues in drone-based delivery systems. In contrast with the abovementioned works, in [23], the authors presented a unique perspective by emphasizing the public mindset towards adopting the drone-based delivery service. The authors addressed the user mindset on drone-based logistics and their intention on adopting such services. They concluded that people's mindset varies with their residing area. In [24], the authors focused on hybrid delivery techniques that included trucks and drones. The authors provided background knowledge of the recent progress on the drone-based delivery systems, followed by a novel classification of truck-and-drone-based delivery systems. The comparison of different studies is also given in terms of design objectives, solution techniques, role of the vehicles, and overall system configuration. In particular, the authors discuss three different configurations of hybrid truck- and drone-based delivery systems: single truck--single drone, single truck--multiple drones, and multiple truck--multiple drones. In [25], the authors surveyed drone scheduling techniques for various purposes such as parcel delivery, recharging considerations, and monitoring, which are equally important for designing drone-based logistics systems. They summarized the existing studies in terms of various crucial parameters such as objectives, number of drones and vehicles, solution of the problems, and innovative ideas. They focused only on the drone scheduling aspect and ignored other dominant concerns in drone-based logistics. In [26], the authors investigated why customers are reluctant to adopt drone-based food delivery systems. Specifically, the authors designed a unique framework to explain several barriers such as value, risk, experience, and tradition in customers' unwillingness to adopt drone-based food delivery. This survey is particularly important because it reveals the perception of customers. This can significantly improve the drone-based food delivery service. To understand the customers' mentality towards adopting drone-based logistics systems in a pandemic situation such as COVID-19 [27], the authors in [28] particularly focused on the determining factors that encourage or discourage the adoption of such services.