Underwater SLAM for Structured Environments Using an Imaging Sonar

This book is a revised version of the doctoral dissertation presented by D. Ribas in the Department of Computer Engineering at the University of Girona. The main purpose of this work is to present different techniques developed with the objective of providing a solution to the navigation problem for Autonomous Underwater Vehicles (AUVs) operating in structured environments, with special attention to localization techniques but, particularly, to the application of SLAM (Simultaneous Localization And Mapping) techniques as a self-contained system which requires neither previous knowledge of the scenario nor the use of absolute positioning systems like GPS, LBL or USBL. This book also presents techniques for feature extraction capable of dealing with the particular complexities of a mechanically scanned imaging sonar. The approaches described in this book are designed for use in structured environments like those present in many industrial scenarios, specifically for scenarios containing manmade structures in the form of rectilinear walls like those met in harbours, breakwaters, marinas, canal systems, etc. Although most of the previous work done in this field focuses on open sea and coastal applications, obtaining an accurate positioning in such scenarios would increase AUVs capabilities notably, allowing to perform autonomously tasks such as inspection of underwater structures, surveillance of marine installations and even enabling autonomous harbour leaving and returning operations.