Hover Control of Thrust Vectoring VTOL Flying Wing - Modeling, Control and Development of Test Platform with Experimental Results

Abstract

This work consists of theoretical and practical advances in the development of a fully thrust-vectoring hybrid vertical take-off and landing (VTOL) unmanned aerial vehicle (UAV). A high-fidelity dynamic simulation model is successfully implemented in Matlab and Simulink based on a 10 DOF Euler-Lagrange approach, including actuator dynamics and external aerodynamic forces. A reformulation of a previously proposed control allocation scheme is presented based on quadratic programming (QP). The proposed model and control allocation method is verified through simulation. Simulation results show that the vehicle is able to track attitude and velocity commands. The inertial properties and propeller parameters used in simulation are based on CAD-models and propeller tests of an actual prototype UAV developed by Sevendof AS. Further, a test platform for autopilot implementation, including software-in-the-loop simulation (SITL), is developed based on the open-source software frameworks PX4 and Gazebo. The implemented autopilot successfully stabilizes the vehicle in SITL simulation, and is further verified through flight tests in an indoor test rig. The flight experiments show that the proposed autopilot solution succesfully stabilizes the attitude and velocity of the prototype vehicle.