Quadrotor Aggressive Deployment, Using a Quaternion-Based Spherical Chattering-Free Sliding-Mode Controller

This paper introduces a nonconventional approach for autonomous multirotor UAV deployment, in which a quadrotor is aggressively launched through the air with its motors turned off. A continuous quaternion attitude trajectory is proposed to safely recover the vehicle into a hover mode. Then, an operator could take the command or continue a desired mission in the autonomous mode. The controller is a chattering-free sliding mode algorithm based on the geometrical properties of quaternions and axis-angle rotations. Lyapunov theory is used to analyze the system stability. The proposed methodology is validated in real-world indoor and outdoor experiments.