시간지연제어기법을 이용한 헥사콥터 고장허용 제어 = Fault Tolerant Control of Hexacopter UAV using Time Dealy Control Scheme

다국어 초록 (Multilingual Abstract)

Multi-rotor unmanned aerial vehicles (UAV) have been adopted in many areas in recent years. If one or multiple actuators failure occurs during flight, the UAV may not be able to maintain a controlled flight or even worse, it could be crashed due to lose of control authority. Likewise, if a conventional quadrotor is subjected to a failure of a rotor, it may exhibit unacceptable performance even if fault tolerant control (FTC) method is adopted. In order to overcome the drawback of the quadrotor, the hexacopter, which has six rotors instead of four, has been developed to increase reliability and controllability even at the mechanical fault conditions such as degradation of motor performance or even worse electric motor failure. A novel attitude tacking control method using Time Delay Control (TDC) scheme is developed to provide robust controllability of a rigid hexacopter in case of single or multiple rotor faults. When the TDC scheme is developed, the rotor faults such as the abrupt and/or incipient rotor faults are considered as model uncertainties. The kinematics, modeling of rigid dynamics of hexacopter, and design of stability and controllability (SCAS) are addressed rigorously in this paper. In order to compare the developed control scheme to a conventional control method, a nonlinear numerical simulation was performed and the attitude tracking performance was compared between the two methods considering the single and multiple rotor faults cases. The developed control scheme shows superior stability and robust controllability of a hexacopter that is subjected to one or multiple rotor faults and external disturbance, i.e., wind shear, gust, and turbulence.