本研究之主要重點有二：無人船的路徑規劃與無人船的控制系統設計與實現。在地圖中搜尋最短路徑是一熱門問題，其中最被廣泛應用的演算法為A*演算法，然而傳統的A*演算法(A* on Grids)的轉彎角度被限制住，所以無法找到真實最短路徑，因此本研究提出Finite Angle A* (FAA*)演算法來改善傳統A*演算法的缺失，本研究驗證了FAA*演算法所搜尋的路徑比A* on Grids 以及 A* Post-Smoothed還要來的短。除了搜尋最短路徑外，本研究亦探討導安全路徑問題，因為當最短路徑存在至少一個轉彎時，則轉彎處必與障礙物相交，在實際導航時可能會產生碰撞，而為了使路徑規劃之結果能夠實用，因此本研究提出另一個可目視直線定義來規劃出一條與障礙物保持安全距離的最佳路徑。
本研究利用完整的空照圖庫並配合影像分析技術來獲得FAA*演算法所使用的地圖，大量減少製造地圖的成本以及時間，再透過座標轉換將規劃的結果實用於無人船上。
本研究設計了適用於雙直流推進器的無人船的模糊控制器，配合GPS模組以及電子羅盤則可成功實現無人船的自主導航，本研究亦於港灣實際測試無人船，測試結果顯示出本研究設計的模糊控制器能夠成功的自主導航無人船。

In recent years, the development of autonomous surface vehicles has been an area of increasing research interest. The presented study focuses on two objectives: the path planning for unmanned surface vehicle (USV) and the design of fuzzy logical controller of USV. Experimental tests of USV are also described in this research.
Path planning is an essential topic of robotics, and the main purpose in this investigation is to determine approximately the safest and shortest path. A* algorithm is the most commonly used for path finding, but the paths found by A* are not truly the shortest paths because the potential headings of the paths are artificially constrained. To tackle this shortcoming, the Finite Angle A* (FAA*) method is proposed in this study. The experimental results show that FAA* finds shorter paths than both A* on grids and A* with the post-smoothed method. Despite these results, FAA* is also not guaranteed to determine the shortest path. The true shortest path is composed with a set of lines tangent to the obstacles on the map, which means that this path is not collision-free, and this situation makes discovering the shortest path impractical. Hence, finding a safer path that is as short as possible is our primary goal. The modified definition of line-of-sight is proposed to achieve this objective by adding a variable called “safe distance” to the line-of-sight formula, and the value of the variable can be decided by its users.
The image analysis is utilized to convert color satellite images into binary images which can be used as the maps of FAA*. The satellite image is built based on the world geodetic system; therefore, the results of the output path are also dependent on this system. The results can be directly used on USV which has a GPS navigation system. The proposed procedure can reduce the cost of creating maps for USV.
In this article, fuzzy logic navigation is presented. The fuzzy controller of USV is designed to automatically control two DC brush thrusters. The input variables of the fuzzy controller are provided by the GPS module and electrical compass. Furthermore, the output variables are used as Pulse Width Modulation (PWM) for the DC thrusters. Finally, the USV trial is successfully completed in Anping harbor, and the experimental results illustrate that the USV can autonomously cruise along the path found by FAA*.

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