請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/26509
標題: | 側掃聲納掃瞄線即時海床分類以輔助無人水下載具導航之研究 Real Time Seafloor Classification Using Sidescan Sonar Scanlines for Unmanned Underwater Vehicle Navigation |
作者: | Sheng-Wei Huang 黃盛煒 |
指導教授: | 郭振華 |
關鍵字: | 無人水下載具,側掃聲納,水下目標物偵測,海床分類器,適應性閥值, UUVs,side-scan sonar,seabed classifier,target detection,adaptive threshold, |
出版年 : | 2008 |
學位: | 碩士 |
摘要: | 無人式水下載具常用來執行水下測繪、水下監控等任務,無人式水下載具是一種有自身定位系統來提供位置資訊的穩定感測平台。然而,由於缺乏預設的地標,因此無人式水下載具在未知環境下的導航仍是一大挑戰,發展海床即時特徵偵測能力對水下無人載具的導航有相當大的助益。本文提出一套利用側掃聲納掃描線即時地偵測水下目標物的方法,此方法主要包含三大部分:前處理器讓資料訊號增強並降低資料量和運算時間、偵測器可以辨識出有包含目標物的掃描線並用適應性閥值突顯出目標物、定位器則可以消除載具運動造成的目標物定位誤差。利用此方法實作在無人載具上即時偵測水下目標物,利用兩個實驗說明沙床上的水泥目標物的訊號和格網圖。未來,這個方法還可以結合導航系統發展出在未知環境中自我定位並建圖的準確導航系統。 Unmanned Underwater Vehicles (UUVs) have been employed in tasks such as hydrographic survey, underwater surveillance. UUVs are stable sensor platforms with positioning capabilities. However, navigation of UUV in unstructured environments is a still challenging problem due to the lack of predefined landmarks on the sea floor. Developing real time seafloor features detection capability will be beneficial for the UUV navigation. The aim of this work is the development of a real-time method of target detection by the processing of side-scan sonar sscanlines. The detection process has three parts. Firstly, a pre-processing step is used to filter the data and to reduce computation time. Then a detector is designed to categorize the target content in a scanline and represents targets with an adaptive threshold. Finally, target positions are corrected based on the motion of the UUV. This procedure was implemented on an UUV to verify the landmark detection capability in real time. Two experimental results conducted on sandy seabed with concrete targets are demonstrated to show their signal contents and the final grid maps that are ready for UUV navigation purpose. The detection method developed in this work enables UUVs to build sea floor map for the self localization in an unstructured environment. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/26509 |
全文授權: | 未授權 |
顯示於系所單位: | 工程科學及海洋工程學系 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-97-1.pdf 目前未授權公開取用 | 2.05 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。