現今運輸物體是自動化機器人主要的應用，自動化工廠已經廣泛使用地面機器人作為運輸平台。相較於地面機器人容易受到地形限制，空中機器人可以在任意的地形上移動，但飛行器的負載重量遠低於地面機器人。在許多研究中，對於重量較重的物體，已經使用多架飛行器運合作輸物。然而，在特定的環境中，空中的區域並不一定是寬敞的，對於一些複雜的環境，在使用多架飛行器合作運輸時，需要透過變換姿態才能在環境中移動。
在本論文中，我們提出一個使用雙架飛行器的合作運輸系統，在運輸過程中可以任意變換負載的姿態。在系統中，每架飛行器都配置一個閉迴路系統，在飛行器之間無溝通的情況下，搭配行進策略完成任務。飛行器的閉迴路系統使用俯視負載的攝影機影像，檢測負載上的標記，並估算出負載的位置與姿態，透過固定增益的水平移動、垂直移動和旋轉的PID控制器給予飛行器移動的命令。
我們在模擬器中實現了我們提出的系統，並設計一個需要改變負載姿態才能通過的實驗環境，透過不同條件的實驗，以及在實驗環境中加入風的影響，驗證了系統的穩定性。

Nowadays, object transport is the main application of automated robots, and ground robots are widely used in automated factories as a transport platform. In comparison with ground robots, which are subject to terrain constraints, aerial robots can move on any terrain, although with a much smaller load capacity than that of ground robots. In many studies, multiple drones have been used to cooperatively transport heavier objects. Nevertheless, in a specific environment, the space over the terrain is not necessarily spacious. For some complex environments, when multiple drones are used for cooperative transportation, it is necessary to change the attitude of the drones to make them pass through the specific environment.
In this study, a cooperative transport system using two drones is proposed, which could arbitrarily change the load attitude during the transportation process, where each drone, equipped with a closed-loop system, completed its task in conjunction with the routing strategy in case of no communication between the drones. The closed-loop system of the drone used a camera overlooking the load to detect the markings on the load to assess the position and attitude of the load, where the Proportional-Integral-Derivative controllers gave the drones the command to move horizontally, vertically, and rotarily through a fixed gain.
In the simulator, we implemented the proposed system and developed an experimental environment requiring a change in the load attitude for the drones to pass through. The stability of the system was verified by various experiments, with the addition of wind effect.

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