Finite-time formation tracking control with collision avoidance for quadrotor UAVs

In this paper, the distributed finite-time formation tracking control problem with collision avoidance is investigated for multiple quadrotor Unmanned Aerial Vehicles (UAV) subject to external disturbances. Firstly, two finite-time observers are designed to estimate the external disturbance force and torque without upper bound, respectively. Then, utilizing the precisely observed information deriving from the observers, a novel sliding mode surface-like variable based distributed position formation tracking control strategy and a fast terminal sliding mode based attitude tracking control strategy are proposed, respectively. It achieves that the multiple quadrotor UAVs can track the desired trajectory in a specific formation configuration within the safe distance and avoid dynamic obstacles. Meanwhile, the rapid attitude synchronization and tracking is also achieved. The entire multiple UAVs distributed formation tracking closed-loop control system are proved to be globally fast finite-time stable by using Lyapunov-like analysis. Finally, the effective and fine performance of the proposed schemes are demonstrated by a numerical simulation example with a group of quadrotor UAVs.