UAV Coverage Using Hexagonal Tessellation

Unmanned aerial vehicles (UAVs) are increasingly being used for coverage applications. Some common examples include inspecting agricultural fields for certain plant diseases, tracking wildfire, photogrammetry, flying over an area to find avalanche victims, and several other search and rescue operations. Although fixed-wing UAVs can survey large areas more quickly and have a better battery lifetime compared to multirotor systems, they fail to provide a close up inspection of a certain area by hovering over it. Quadrotors provide excellent inspection capabilities; however, they have notoriously short battery lifetimes. In this paper, we propose a coverage algorithm through hexagonal tiling of a target region. We present a coverage path using the average distance, d, that can be travelled by a drone on a single charge, and the radius, r, of the viewing cone of a typical downward facing camera mounted on it as parameters. We compare our method with classical zigzag coverage pattern. Our results show that for large enough regions, the Hamiltonian circuit that passes through the centers of the tiling hexagons produces a shorter path.