Research on Formation Keeping of Multi-rotor UAVs Based on Improved Virtual Structure Method

Abstract

Multi-UAV cooperative formation flight (CFF) can greatly improve the damage resistance and mission completion efficiency of single UAV, so it has become a research hotspot in recent years. The entire process of multi-UAV formation flight can be decomposed into target tracking, formation keeping, obstacle avoidance and collision avoidance. The research of formation keeping mainly uses the leader-follower or virtual structure method. The former has the problem of single point of failure, and the formation error will be amplified step by step. The latter is difficult to select virtual leader, and is hard to adjust the formation adaptively with limited communication conditions. Based on the virtual structure and multicast method, this paper proposes a recursive fusion strategy which reduces the requirement of communication frequency between UAVs, increases the adaptability of formation to single point of failure, and improves the accuracy and adaptability of formation keeping to a certain extent. On this basis, the cascade PID model is used to design the formation controller. Finally, the effectiveness of the strategy is verified by using MATLAB.