本論文設計一種用於戶外多架無人機追隨控制的即時干擾估測與固定時間補償（RTDE-FTC）方法，以解決具有干擾的追隨控制問題。所建議的控制器可應用於不同的內迴路PID控制的無人機，而所設計的多架無人機追隨控制的即時干擾估測與固定時間補償，將應用於其外迴路的二階系統並具有未知干擾，例如，感知器雜訊、系統不確定性或額外的陣風。為執行監控任務，定義虛擬領導者為領隊飛行無人機的期望三維路徑。每架跟隨無人機以RTDE-FTC控制追隨前面的無人機，以維持所設定編隊。所設計的追隨控制器包括兩部分：(i)等效控制管理相鄰無人機之間的距離和即時干擾補償，(ii)使用具有非線性增益的切換控制，以處理每架無人機內部的干擾或額外的陣風，確保穩健的隊形飛行。切換增益會在接近零耦合追隨誤差時自動放大，以應付更多的不確定性及實現快速的有限時間追蹤能力。最後，比較與內迴路PID控制（無論是否有額外陣風的干擾），並以兩種三維軌跡隊形，證實所提出之RTDE-FTC的有效性及優越性。

In this thesis, a real-time disturbance estimation and fixed-time compensation (RTDE-FTC) for outdoor multi-UAV following control is designed to tackle following control with disturbance. In contrast to the inner-loop PID control in each UAV, the outer loop control design employs a second-order system representation to accommodate unknown disturbances such as wind gusts, system parameter uncertainties, and initial pose and velocity errors. To perform a surveillance task, a virtual leader defines the desired 3D path for a team of UAVs flying in formation. Each UAV follows the one in front, while the RTDE-FTC control system guarantees their coordinated movement. The proposed following control includes two strategies: (i) equivalent control manages the distance between neighboring UAVs and real-time compensates the estimated disturbances, and (ii) switching control with a nonlinear gain tackles individual uncertainties within each drone and the remaining uncertainties to ensure a robust formation flight. To achieve fast finite-time convergence, the switching gain automatically scales up near zero coupled error. Finally, the comparison with inner-loop PID control with and without extra wind disturbance are presented to confirm superiority of the proposed RTDE-FTC

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