本論文以四輪移動車輛作為控制平台，結合雲端功能，完成四輪移動車輛的路徑追蹤控制，其中該四輪移動車輛具有兩組驅動馬達，分別驅動左前後輪與右前後輪。控制平台是以單板電腦(single-board computer)作為控制的核心，透過無線網路連結至雲端資料庫，並使用全球定位系統(GPS)和微控器(Microcontroller)，用來取得車輛的位置資訊和驅動四輪移動車輛移動，另外配合霍爾元件偵測兩側車輪轉速，並回授轉速資料至控制器以完成四輪移動車輛的速度控制。為了完成四輪移動車輛之路徑追蹤控制，利用Pure Pursuit Algorithm規劃路徑追蹤時移動的軌跡，並結合PID控制器完成四輪移動車輛路徑追蹤的控制。最後，本文針對四輪移動車輛路徑追蹤功能的效果進行實驗，以驗證本文所使用的方法的可行性，並透過實驗數據分析此控制方法的效能。

The objective of thesis is to develop a trajectory tracking control system with a cloud database for a four-wheeled vehicle. The vehicle has two driving devices. The first one is a left-driving device that simultaneously drives left-front and left-rear wheels. The second one is a right-driving device that simultaneously drives right-front and right-rear wheels. The kernel of the control system is a single-board computer that is connected to the cloud database with wireless network, and a microcontroller is used to drive the four-wheeled vehicle. The location and speed feedback data of the vehicle are obtained by global positioning system (GPS) and wheel with Hall effect sensors, respectively. The pure pursuit algorithm obtains the cloud-based moving trajectory of the four-wheeled vehicle, and the PID controller achieves the trajectory tracking control. Finally, some experimental results are given to verify the effectiveness of the cloud-based moving trajectory tracking control.

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