5.1 結論
本論文提出了一個全向式移動平台結合全向式攝影機的定位系統設計,以 基於EKF-SLAM之演算法,和全向式攝影機對環境做觀測,修正全向式機器人的 打滑誤差,並在全向式機器人移動的同時,能夠建立出環境地圖且定位出機器人 的位置。
以所推導出之全向式機器人運動模型,及不同地點對特徵點的觀測視角,
推算出特徵點相對於機器人本身的距離關係,以此資訊做為定位系統的輸入。使 用SLAM演算法解決機器人之定位及地圖建立的問題,達成EKF-based SLAM演 算法。結合影像處理與SLAM演算法,實現在全向式機器人平台上。
論文中以實驗驗證定位演算法:手動遙控機器人來回行走約12公尺後起點 與終點誤差平均為0.07公尺,於室內繞方形3圈及走8字形軌跡起點與終點的x及y 方向誤差均在0.10公尺以內。並以情境模擬實驗結果證實機器人藉由此演算法的 幫助,為在實驗室622繞行一圈後走出房門,沿走廊移動約11公尺進621門,之後 再沿原路回到622。另加入了機器人於長距離移動中同時轉向的實驗,發揮了全 向式機器人靈活移動的特性,並同時建立其沿途路徑的特徵點環境地圖,完成全 向式移動機器人的室內導航功能。
5.2 未來工作
在本論文中之定位演算法約需耗時2秒左右,此運算時間在較為慢速的測試 實驗中雖然可行,但在實際的應用中若是到了更複雜的環境,改變就不能有及時 的反應,且若在機器人的移動速度加快的情形下,影像運算也不能作及時的反
應,影響定位結果的正確性。因此在影像處理及定位演算法的設計上可以再加以 改善,提升整體定位系統的效能。
全向式攝影機常被用於多機器人系統上,而本論文發展出的基於全向攝影 機之機器人定位方法亦可與之整合,並藉由全向式移動平台的高機動性,讓機器 人不僅能夠觀測機器人隊伍中的隊友,也讓機器人能對周遭整體的環境做估測,
更迅速地移動至目標點,增加多機器人隊伍的實用與功能。
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