A novel leader-following strategy applied to formations of quadrotors

This paper presents a strategy for formation control of autonomous vehicles using a leader-following approach. A trajectory planner prescribes the motion of a group of virtual vehicles, using a Lyapunov-based nonlinear controller that stabilizes the position of the leader in the reference frame of the virtual vehicles at a predefined distance vector. This strategy differs from the standard approach of defining the desired distance vector in an inertial frame and can be used to obtain rich formation trajectories with varying curvatures between vehicles. By imposing adequate constraints on the motion of the virtual vehicles, the planner naturally guarantees the generation of valid formation trajectories, without requiring the parametrization of the space curve described by the leader. The trajectories are generated online and provided to a trajectory tracking controller specifically designed for quadrotor vehicles. Results of experimental tests are presented demonstrating the performance of the proposed solution for formation control of autonomous vehicles.