New multi-UAV formation keeping method based on improved artificial potential field

Formation keeping is important for multiple Unmanned Aerial Vehicles (multi-UAV) to fully play their roles in cooperative combats and improve their mission success rate. However, in practical applications, it is difficult to achieve formation keeping precisely and obstacle avoidance autonomously at the same time. This paper proposes a joint control method based on robust H∞ controller and improved Artificial Potential Field (APF) method. Firstly, we build a formation flight model based on the “Leader-Follower” structure and design a robust H∞ controller with three channels X, Y and Z to eliminate dynamic uncertainties, so as to realize high-precision formation keeping. Secondly, to fulfill obstacle avoidance efficiently in complex situations where UAVs fly at high speed with high inertia, this paper comes up with the improved APF method with deformation factor considered. The judgment criterion is proposed and applied to ensure flight safety. In the end, the simulation results show that the designed controller is effective with the formation keeping a high accuracy and in the meantime, it enables UAVs to avoid obstacles autonomously and recover the formation rapidly when coming close to obstacles. Therefore, the method proposed here boasts good engineering application prospect.