在本論文中，我們設計一種基於具有抗風阻能力的干擾觀測器之有限時間跟隨控制（DO-FTFC-WRC），以快速實現在無GPS訊號的區域，例如倉庫、圖書館中，對多架無人機進行指定跟隨任務。每架無人機中的底層PID跟隨控制（LL-PID-FC）視為一個內部控制迴路。相反，它的外部迴路由一個具有未知干擾的二階系統模式，包括系統不確定性、感知器雜訊或額外的風勢。將領隊跟隨想要的三維姿態設為虛擬領隊。接著，隨後的追隨者逐一執行所設想的隊形。為了在不確定的環境中完成任務，所設計的DO-FTFC-WRC具有耦合的跟隨誤差、非線性切換增益，及干擾觀測器以估測每架無人機中的動態不確定性。不僅非線性切換增益隨著耦合的跟隨誤差接近零而增加，以完成其快速有限時間追蹤能力，同時以干擾觀測器即時補償不確定性。最後，通過模擬和實驗，與LL-PID-FC相比，考慮或不考慮更多的風條件，以代表性的“向前-順時針180度-往後運動”軌跡，驗證所提方法的優越性。

關鍵詞：干擾觀測器，有限時間跟隨控制，多無人機，李雅普諾夫穩定性理論，底層PID跟隨控制。

Abstract---In this thesis, a disturbance-observer-based finite-time following control wind resistance capability (DO-FTFC-WRC) is designed to quickly accomplish an assigned following of multiple UAVs in a GPS-denied region, e.g., warehouse, library. The low-level PID following control (LL-PID-FC) in each UAV is an inner control loop. In contrast, its outer loop is modeled by a second-order system with unknown disturbance, including system uncertainties, sensor noises or extra wing gust. The virtual leader is modeled as the desired 3D pose for the leader to follow. Then the consequent followers are one-by-one to execute the desired formation. To fulfill the task under the uncertain environment, the proposed DO-FTFC-WRC possesses coupled following error, nonlinear switching gain, and disturbance observer for estimating dynamic uncertainties in each UAV. Not only does the nonlinear switching gains increase as the coupled following error is in the vicinity of zero to achieve its fast finite-time convergence, but also the uncertainties are online compensated by disturbance observer. Finally, the simulation and experiment in comparison to LL-PID-FC with or without wind condition for a representative “forward- clockwise turning-backward motion” are presented to validate the superiority of the proposed approach.

Key words: Disturbance observer, Finite-time following control, Multiple UAVs, Lyapunov stability theory, Low-level PID following control.

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