Time Varying Formation Control of Unmanned Aerial Vehicle Multi-Agent Systems with Unknown Leader Input

Time-varying motion consensus and formation control of leader-follower unmanned aerial vehicle multi-agent system (UAV-MAS) is studied, in this paper. It is assumed that the number of agents changes during the motion. According to the variations in number of agents, the desired formation would also change in the form of various regular polygons in such a way that, whose sides, which are the relative distances of the neighboring followers from each other, are kept constant. A two-loop controller is provided, in which, the internal loop uses the feedback linearization control law to linearize the dynamics of the agents. In the outer loop, an integral state feedback controller is employed as a new consensus formation controller based on the relative position and velocity vectors of neighboring agents. The followers do not know the path of the leader and only maintain the formation and track the leader by maintaining their relative distance with their neighbors. Controller coefficients are determined offline by solving the algebraic Riccati equation and based on the graph theory. Therefore, no online tuning is needed.  Closed loop stability of system under the proposed control law would be investigated via the Lyapunov stability theorem and various simulations are performed to illustrate the capability of the proposed controller.