Control Augmentation System Design for Quad-Tilt-Wing Unmanned Aerial Vehicle via Robust Output Regulation Method

Quad-tilt-wing (QTW) configuration is a promising one for airplanes to achieve vertical take-off and landing (VTOL), which has a pair of tandem wings that can tilt from vertical to horizontal positions. This unique configuration allows the aircraft to perform a VTOL as well as fly at high cruising speed. For that reason, QTW unmanned aerial vehicles (UAV) have vast potential in civil applications. However, designing a controller to stabilize and control the attitude of QTW UAV is a challenging mission since the aerodynamic characteristics of the aircraft greatly change in accordance with the wing tilt angle. Based on the previous work, this paper examines the possibility for improving the tracking performance of the QTW UAV by the application of the modified robust output regulation method. An experiment was conducted to examine the control performance of the designed controller.