Dynamic Feedback Linearization of Flying Wings With Real-time Newton-Raphson Iterations

This paper details development of a dynamic feed-back linearization controller tailored to trajectory tracking of hybrid UAVs with a (tailsitter) flying wing topology. First, a differential flatness transform is presented using a simplified aerodynamic model with negligible lateral forces. The proposed controller derives from the flatness transform. For every state we can determine a collection of flat trajectories that correspond with that state. From that collection, we choose a flat trajectory that converges smoothly to the reference flat trajectory and apply the flat inverse dynamics to compute a suitable control input. To remedy the lack of an explicit inverse of the forward dynamics, we propose a dynamic inverse mapping approach which keeps the control algorithm computationally affordable. We evaluate and compare the control architecture with state-of-the-art cascade control in simulation.