Abstract: Aiming at the problem that multi-UAV system is prone to collision when using finite-time ring formation algorithm to perform ring formation tasks, this paper proposes a multi-UAV finite-time ring formation control algorithm based on improved artificial potential field method. A set of auxiliary potential fields perpendicular to the direction of obstacle movement are introduced, which avoids the internal collision of multi-UAV in the process of rapid formation, and solves the problem that traditional artificial potential field method is easy to fall into local optimal solution. In order to verify the effectiveness of the proposed algorithm, computer simulation experiments are carried out under the same parameters such as the initial position of the UAV, the influence range of the potential field and the surrounding radius. The results show that the proposed algorithm can effectively avoid the collision of multiple UAVs in the ring formation process. In order to further verify the practicability of the algorithm, this paper uses three"X"rotor UAVs with axial distance of 450 mm to carry out physical experiments. The experimental results show that the proposed algorithm has good collision avoidance effect when completing the ring formation of multiple UAVs in limited time.

Key words: multiple UAVs, finite-time circular formation algorithm, improved artificial potential field method, circular formation control, collision avoidance control