Time-Varying Formation Planning and Distributed Control for Multiple UAVs in Clutter Environment

In this article, we present a novel method to achieve optimization based obstacle avoidance and distributed regular polygon time-varying formation control for multiple unmanned aerial vehicle systems (UAVs) in clutter environment. Under a leader-following structure, directed communication graph is considered. The formation size is time-varying and the trajectory of the leader UAV is planned in real time. Different from most of the existing trajectory planning algorithms for single UAV, an optimization-based safe trajectory and formation size online planning algorithm are proposed. To deal with information loss caused by directed communication topology, distributed smooth adaptive filters are designed for each UAV to asymptotically estimate the safe trajectory and formation size. Besides, a geometric tracking controller is adopted to track the desired trajectory for each UAV. Experimental results are provided to demonstrate the effectiveness of the proposed method.