Sidescan Sonar Mapping Using Sonar Scanlines for Unmanned Underwater Vehicles

• Main Authors: Wei-Han Wang, 王偉翰
• Other Authors: 郭振華
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/90620850577537773638

碩士 === 國立臺灣大學 === 工程科學及海洋工程學研究所 === 97 === Navigation of UUV in unstructured environments with accurate positioning capabilities still is a challenging problem due to the lack of predefined landmarks on the sea floor. The aim of this work is the development of a method for target detection by the processing of side-scan sonar scanlines. The detection method developed in this work enables UUVs to build seafloor map for the self localization in an unstructured environment. The detection procedure has two steps. Firstly, a pre-processing step is used to filter the data and to reduce computation time. Then a detector is designed to detect the target position in a scanline. After detection procedure, for the purpose to obtain the whole map of the environment, the occupancy grid mapping method was applied to combine the detect result and the acoustic wave of side-scan sonar in sea water. Finally, trajectory of the UUV could be estimated by motion of the vehicle. This procedure was implemented on an UUV to verify its landmark detection capability. Experimental results conducted on sandy seabed with concrete targets are demonstrated with their signal contents and the final grid maps that are useful for UUV navigation purpose.