現今許多研究人員致力於開發自主移動機器人之室內定位技術。透過不同的傳感器、設置及演算法，他們提出各種解決方案來實現不同的需求。而本篇論文提出一種基於天花板特徵的導航系統，藉由裝置於自主移動機器人上方之2D攝影機獲取天花板的影像資訊，進而達到簡化並且通用的室內定位方法。
此定位方法乃透過一裝於機器人上方且朝向天花板的攝影機來獲取天花板的影像特徵，藉由此資訊機器人即可判斷其位置。此方法的好處是相較於其他定位方法，無需複雜的環境設置，且不受輪胎打滑的影響，因此儘管持續運行一段時間後，仍然沒有累計誤差。且對於任何不同的環境，可以在簡易的初始化過程之後快速地建立系統，並在指定的工作區中進行機器人之室內定位及導航。
本論文主要利用影像拼接演算法來建立天花板之全景資訊，並且採用改進過後的影像匹配演算法以計算機器人在地板上的位置及姿態。其中，在缺乏自然特徵的天花板中，利用雷射投射裝置在天花板上投射人工特徵。藉由此裝置，機器人即可在天花板缺少特徵的環境中進行室內定位、導航。論文的最後，透過一連串的實驗來驗證此方法的可行性。

Nowadays, many researchers work on indoor localization techniques for an autonomous mobile robot. By means of different sensors, setups, and algorithms, they proposed a variety of solutions to reach diverse goals. Focusing on providing a simpler setup and general solution, this thesis proposed a ceiling-feature based navigation system by using a 2D camera to capture ceiling images and localize the robot.
The proposed localization method uses an overhead camera on the robot to capture the image features on the ceiling for localizing itself. The advantage of this method is unsophisticated preprocessing, not affected by tire-skidding and no accumulation errors after executing a period of time. The system could be easily and rapidly set up after a simple initialization process for any different environment and could localize and navigate the robot in the required workspace.
This thesis uses the stitching algorithm to build the panorama of the ceiling information and uses the improved matching algorithm to calculate the robot position and pose on the floor.
A laser projection device is implemented in this work to generate artificial landmarks on the ceiling which lacks features for recognition. With it, the robot can navigate itself in a designated floor space under a ceiling without features.
A number of experiments show the feasibility of the proposed navigation system.

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