Human-UAV Collaborative Search with Concurrent Flights and Re-Tasking

This thesis discusses a system that allows an operator to use two unmanned aerial vehicles (UAVs) to search an area. Prior work accomplished this in separate survey and search missions, and this work combines those two missions into one. The user conducts a search by selecting an area to survey, and the first drone flies above it, providing up to date information about the area. Points of interest (POI) are then marked by the user and investigated by the second drone. This system assumes a static and known obstacle map, and segmenting the environment during the missions leaves potential for future work. Both drones are equipped with cameras that stream video for the user to observe. A custom graphical user interface (GUI) was created to allow for the drones to be controlled. In addition to marking a search area and POI, the user can pause the drone and delete or add new POI to change the mission mid-flight. Both drones are commanded remotely by a ground station (GCS), leaving only low-level control to the onboard computers. This ground station uses a nearest neighbor solution to the travelling salesman problem and a wavefront path planner to create a path for the low altitude drone. The software architecture is based on the Robot Operating System (ROS), and the GCS uses the MAVLink messaging protocol to communicate with the drones. In addition to the system design, this paper discusses UAV human interaction and how it is applied to this system.