Coordinated UAVs for Effective Payload Delivery

Recently, drones emerged as a promising approach for transporting payloads to remote and difficult access areas. In this paper, an experimental payload delivery system that leverages the use of two unmanned aerial vehicles (UAVs) is implemented. A local and web remote monitoring and control system is developed through the design of a ground control station (GCS) for a pre-planned autonomous trajectory flight. Then, two autonomously guided and coordinated UAVs are built and used to transport a payload to a remote area where the target way points are selected on the GCS interface by the user and the mission is monitored in real time. A custom communication protocol is implemented to use one UAV as a relay between the GCS and the second UAV. Cable material payload delivery for bridge construction is selected as a case study in real-world experiments conducted at the Virginia Tech's Drone Park. The experimental results thoroughly evaluate the performance of the implemented UAV delivery system. In particular, the experiments related to the flight missions were successful after several tests and adjustments. In addition, the experiments are used to assess the telemetry and commands latency among UAVs and GCS using the age of information metric in order to identify the optimal UAVs distances and positions during the mission flight patterns.