Optimal flight path planning for UAVs in 3-D threat environment

Nowadays, the environments surrounding modern battlefield are becoming increasingly complicated, since the threats are not only from the ground but also from the sky. UAV with reconnaissance mission will take more risk when flying along an improper planned path, so path planning of UAV in complex 3-D environments is very significant and challenging. Aimed at the problem, this paper proposes a novel optimal path planning method for UAV based on the flight space partitioning, Dijkstra algorithm and potential field theory. Specifically, under the cases that the locations of threats are assumed to be known and the whole flight space is partitioned into a number of cells and each cell has a safest node. Then, a 3-D network is formed by connecting the nodes of adjacent cells and a shortest suboptimal path is marked on the network with Dijkstra algorithm. Finally, the optimal path is obtained with artificial potential field method. To verify the proposed algorithm, simulation results in two cases are shown.