本論文的目的為設計一套室內導航系統，在不變動外部環境的情況下，經由預先輸入環境地圖與路徑點命令，並透過自身感測器獲得即時環境變化資訊，持續對載具方位進行修正、閃避障礙物，完成自主導航的功能。感測器的部分，使用掃描式雷射測距儀進行路線校正與障礙物偵測，配合輪軸編碼器記錄行進路線；掃描式雷射測距儀將周圍的環境資訊回傳到筆記型電腦中，藉由比對兩次相鄰的掃描資料，找出不變的環境特徵來計算本體位移與平移量，用來校正輪軸編碼器所記錄的路徑偏移；另外，從即時掃描資料偵測移動路徑上的障礙物並迴避，達到即時避障的功能。移動平台的部分，以雙輪機器人載具作為實驗平台，將導航系統裝置在機器人上，使機器人跟據路徑點命令依序進行移動、修正路線，並即時迴避障礙物。最後藉由即時變化的實驗場地與不同的移動路徑，驗證導航系統即使在未知的環境中也可以抵達預先設定的目標點。

In this thesis, the goal is to design a navigation system for an mobile robot by a scanning laser rangefinder and the encoders built in the robot to sense the environmental variation during robot maneavering. To locate the position of the robot, the environmental map and the information of the initial position must be known as a priori. An algorithm of features extraction is thus developed to extract the corner landmarks from the environment scan to estimate the translation and rotation between consecutive scanning data, then correct the error produced by the encoders due to wheels slipping. The location of these particular features is considered to be invariant as compared to the vehicle. They can therefore be used as stable and reliable landmarks in a localization algorithm. And the real-time scanning data can be also used for obstacles avoidance. A wheeled-robot will be adopted as the navigation vehicle, and the whole system will be tested within an unknown environment to validate the performance of the proposed navigation system.

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