Controller Design Using SDRE Method for Tilt-Wing UAV

This paper proposes the flight controller for quad tilt-wing (QTW) UAV during transition flight. QTW-UAV is unstable during transition flight because the dynamic behavior of QTW-UAV exhibits nonlinearity significantly by the change of wing angle. Hence, it is necessary to design the flight controller that guarantees stability under a situation to exist high nonlinearity. The state-dependent Riccati equation (SDRE) control method is one of the solutions of the Hamilton-Jacobi equation when considering nonlinear optimal control problems. The SDRE control method calculates control inputs every control cycle to solve a nonlinear optimal regulation problem. Therefore, this method can design the control system to deal with the change of the wing angle. The effectiveness of the proposed method is shown by numerical simulation.