本論文提供ㄧ基於已確立之超音波感測器模型並配合感測器融合技術，用以改進障礙物格狀地圖建立之方法。首先，對配置在Pioneer P3-DX Mobile Robot上的超音波感測器，進行實驗測試與數學推論以建立適當的感測器模型。用以在偵測障礙物空間時，給定地圖中網格一機率值，來表示該網格存在障礙物之可能性。
再利用Dempster-Shafer 理論進行感測器融合，將網格機率加以結合、運算得出一新機率值，進一步確認該網格存在障礙物之機率。
    隨著機器人移動，地圖內格點資訊不斷地被計算更新。最終便可描繪出一未知環境的輪廓，獲得一正確、完整障礙物格狀地圖，以用於自主機器人之定位、導航等。

This paper provides a sensor fusion approach to improve the accuracy in building an occupancy map based on an established ultrasonic sensor model. 
We first construct a sensor model for the ultrasonic range finders mounted on the Pioneer P3-DX mobile robot by experimental test and mathematical reasoning. Based on the sensor model established, a probability can be assigned to each cell of the grid map that represents the possibility of obstacles. 
Second, by using sensor fusion technique, like Dempster-Shafer theory, probabilities of the cells can be combined to derive a new probability for representing the cell. As mobile robot moves, the probability of cell will be updated continuously. Finally, a complete occupancy grid map for the unknown environment can be established for use in navigation of the autonomous robot.

中文摘要 I
英文摘要 II
目錄	III
圖目錄	V
表目錄	VIII
第一章 緒論	1
1.1 研究背景及動機	1
1.2 研究目的與方法	3
1.3 論文架構	4
第二章 超音波感測器及其模型探討	5
2.1 超音波感測器	5
2.2 感測器模型	8
2.2.1 距離量測實驗	10
2.2.2 角度量測實驗	12
2.2.3 建立感測器模型	16
第三章 感測器融合	25
3.1 Dempster-Shafer理論	25
3.2感測器融合之模擬實驗	30
第四章 以超音波感測資料融合之環境地圖建立	34
4.1 直線走道	36
4.2 ㄇ字型走廊	39
第五章 結論與未來研究方向	45
5.1 結論	45
5.2 未來研究方向	45
參考文獻	47


圖2.1超音波感測器物理模型	6
圖2.2超音波感測器實際波形圖	7
圖2.3超音波感測器量測示意圖	8
圖2.4 Pioneer P3-DX Mobile Robot超音波感測器配置情形	9
圖2.5距離量測實驗之環境	10
圖2.6距離量測實驗過程示意圖	10
圖2.7角度量測實驗之環境	12
圖2.8角度量測實驗過程示意圖	12
圖2.9位於機器人前方兩感測器之量測範圍示意圖	13
圖2.10感測器可測角度邊界修正示意圖	15
圖2.11簡易超音波感測模型	16
圖2.12角度調變函數	17
圖2.13距離調變函數	17
圖2.14有障礙物可能性之容許誤差模型	18
圖2.15無障礙物可能性之容許誤差模型	18
圖2.16由前述實驗為基礎改良之超音波距離模型	19
圖2.17由前述實驗為基礎改良之超音波角度模型	20
圖2.18描述無障礙物情形之改良超音波感測模型	20
圖2.19本論文使用之改良超音波感測器距離模型	21
圖2.20本論文使用之改良超音波感測器角度模型(有障礙物存在時)	21
圖2.21本論文使用之改良超音波感測器角度模型(無障礙物存在時)	22
圖2.22本論文使用之改良超音波感測器三維模型	23
圖2.23改良後超音波感測器模型於障礙物格狀地圖上之呈現	23
圖3.1初始位置示意圖	29
圖3.2三秒後機器人之移動示意圖	29
圖3.3感測器融合之模擬實驗環境	31
圖3.4模擬實驗環境相對位置示意圖	31
圖3.5模擬實驗環境之灰階地圖	32
圖3.6加入障礙物相對位置資訊之實驗環境灰階地圖	33
圖4.1模擬走廊環境所繪製之地圖	35
圖4.2使用距離調變函數調整讀值所繪製之地圖	35
圖4.3淡江大學工學大樓E401教室外走廊	36
圖4.4機器人行進路線圖[直線走道]	37
圖4.5僅依感測器讀值配合簡易超音波模型所繪製之直線走道地圖	37
圖4.6综合前述理論所得之對直線走道感測資訊融合地圖	39
圖4.7工學大樓六樓資工系教授辦公室前走廊	41
圖4.8機器人行進路線圖[ㄇ字型走廊]	41
圖4.9僅依感測器讀值配合簡易超音波模型所繪製之ㄇ字型走廊地圖	42
圖4.10综合前述理論所得之對ㄇ字型走廊感測資訊融合地圖	43
圖4. 11特定角度造成超音波無法順利接收情形	44


表2.1各感測器與中心點之距離關係	9
表2.2距離量測實驗數據	11
表2.3角度量測實驗數據	14

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