Dynamic Feedback Linearization of a UAV Suspended Load System

We present the dynamic state feedback linearization of an unmanned aerial vehicle (UAV) slung load system (SLS) that solves an output tracking problem for payload position and UAV yaw. The suspended payload is modelled as a single pendulum attached to the center of mass of the UAV with a spherical joint. We apply the Dynamic Extension Algorithm (DEA) to design an extended dynamics with full relative degree. A static state feedback linearization of the augmented and extended system provides LTI tracking error dynamics in the linearizing state coordinates. This dynamics is exponentially stable on a well-defined and practical region of state space. The DEA is implemented using symbolic computation software which can be applied to general nonlinear control-affine systems. Closed-loop performance is validated in simulation and compared with a state-of-the-art method from the literature.