Performance Maximization of Longitudinal Flight Stability of Fixed Wing Unmanned Aerial Vehicles with Double Dihedral Angle Variation

As a result of the continuous development of technology, autonomous control and stability of UAVs are of critical importance. Stability, which is a product of the flight performance of aircraft, has been the subject of intensive study and different methods have been put forward to improve it. The aim of this study is to investigate the importance of the change in the longitudinal stability response of an UAV with a morphing wing. The effect of a 1.25 meter wingspan unmanned aerial vehicle with two different dihedral angles on its longitudinal stability is investigated. Longitudinal stability derivative coefficients were obtained. With the stability derivatives obtained separately for nine different wing geometries, the state space model of the UAV was obtained. The resulting state-space model is controlled by a PID controller and the longitudinal stability response is analyzed. As a result, the variation of the return time of the UAV to the equilibrium position with respect to the dihedral angle is obtained.