無人載具避障之導航與控制

Navigation and Control for Obstacle Avoidance of an Unmanned Vehicle

蘇信豪(Hsin-Hao Su)

指導教授 ： 王立昇

共同指導教授 ： 張帆人(Fan-Ren Chang)

國立臺灣大學/工學院/應用力學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.00900

摘要

本論文的主旨為發展一戶外自動導航車系統，系統包含主控站、參考站和無人載具三個部份。無人載具整合了GPS接收機、電子羅盤、攝影機和六個超音波感測器等感測元件，使導航車能追尋路面上預先規劃好之標線軌跡，並在偵測到障礙物進入其運動方向的安全範圍內時，能夠即時進行避障，並藉由全球定位系統（GPS）進行全域定位，以作為當無人載具無法偵測到標線時的控制資訊，且建立由無線網路構成的各次系統資訊交換機制，使主控站得以監控載具行為。
在標線追蹤控制方面，利用樣板相關函數判斷影像中是否存在標線，再經由邊緣偵測、隨機霍氏轉換計算出標線參數，控制方面則採用模糊控制理論，根據標線資訊，經由知識庫推論載具所需要的速度輸出。在避障控制方面，利用VHDL語言配合FPGA開發板設計一控制六顆超音波感測器輸出入電路，再透過超音波感測器得到的距離資訊，利用模糊控制理論設計數個控制器整合六個超音波感測器，經由知識庫推論載具所需要的角度和速度輸出。在定位方面，分別使用載波相位三次差分法（KGPS）和電碼二次差分法（DGPS）進行定位。
本篇論文最後以具體實驗驗證所發展之系統確實可行。

關鍵字

戶外自動導航車 ； 避障 ； 模糊控制理論 ； 載波相位三次差分法 ； 電碼二次差分法

並列摘要

The main theme of this thesis is to develop an integrated navigation and control system for an unmanned vehicle. This system consists of three parts which are main- station, reference-station, and unmanned vehicle. There are various sensors on the vehicle such as GPS receiver, the electronic compass, the camera and six ultrasonic sensors. The vehicle uses camera to detect lanemarkers, ultrasonic sensors to detect the distance between the vehicle and the obstacle, electronic compass to measure the vehicle’s posture and GPS information to determine the vehicle’s position. The data exchange mechanism between sub-systems is set up through wireless network.
The task of tracking is performed such that the vehicle can track along a lanemarker specified in advance and avoid collision with obstacle. The concept of template correlation is used to identify existing lanemarkers in vision. The techniques of Sobel Edge Detention and Randomized Hough Transform are then applied to obtain the parameters of the lanemarker. The operation of six ultrasonic sensors is designed by VHDL language and implemented by FPGA. The KGPS or DGPS is used to set the vehicle’s position. The several fuzzy controllers receive input data from the vision and the ultrasonic sensors, determine the steering angle and velocity of the vehicle. Experimental results show the effectiveness of our proposed navigation and control methodology.

並列關鍵字

unmanned vehicle ； avoid collision with obstacle ； KGPS ； DGPS ； fuzzy

參考文獻

[23] 吳中遠, “即時視覺輔助戶外無人車系統設計與控制”, 台灣大學應用力學研究所碩士論文, 中華民國九十五年七月.

[24] 吳宣誼, “雙無人載具協同控制與實驗”, 台灣大學應用力學研究所碩士論文, 中華民國九十四年七月.

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