Simultaneous calibration of ultrasonic local positioning systems and mobile robot navigation

Resum

This PhD Thesis contributes with the development and improvement of Indoor Localization Systems (ILS) for extensive indoor environments. The GPS is a successful and accepted system for outdoor environments. Since its development, a high number of research lines has emerged to replicate this system in indoor environments due to the potential services that this system can oer in a broad range of applications, such as publicity, social applications, military purposes, medicine, etc. The technologies most used for the development of these systems are infrared, ultrasound, cameras and radiofrequency, being the last one the most extended in the research lines during the last years, due to wireless networks are used in the majority of buildings. The high number of works related to this technology has made difficult to improve systems based on RF, since the knowledge of their limitations in terms of accuracy (several meters) and methods. This Thesis deals with the development of positioning systems based on ultrasonics. These systems present a high accuracy (centimeters) but have the inconvenience of the low coverage range. The common conguration is composed of several beacons that form a Local Positioning System (LPS), so it is neccesary the deployment of several LPSs for covering the whole indoor area, with the difficulty of calibrating all systems (to know the position of the beacons referenced to a map)