Mobile Robots with In-Situ and Remote Sensors for
Real World Gas Distribution Modelling
Víctor Manuel Hernández Bennetts
Akademisk avhandling
Avhandling för teknologie doktorsexamen i datavetenskap, som kommer att försvaras offentligt
Fredag den 20 Frebruari 2015 kl. 13.15, Hörsal L2 (HSL2), Örebro universitet Örebro
Opponent: Prof. Eduard Llobet Universitat Rovira i Virgili
Tarragona, Spanien
Örebro universitet
Institutionen för Naturvetenskap och Teknik 701 82 ÖREBRO
Abstract
Víctor Manuel Hernández Bennetts (2015): Mobile Robots with In-Situ and Remote Sensors for Real World Gas Distribution Modelling. Örebro Studies in Technology 64.
This thesis work addresses the task of gas distribution modelling using mobile robots equipped with gas sensors. Gas Distribution Modelling (GDM) is the artificial olfaction task of creating spatio temporal repre-sentations of the observed gas distribution from a set of relevant varia-bles such as gas concentration measurements. The use of mobile robots in gas sensing related tasks can bring several advantages over conven-tional methods such as manual inspection routines or fixed sensing net-works. For example, the collection of measurements at industrial facili-ties can be automatized, hazardous areas can be inspected without ex-posing human personnel and in emergency scenarios, mobile robots can be rapidly deployed to assist first responders. In these scenarios, GDM is highly relevant since the estimated models can be used to locate gas leaks, identify hazardous areas with high concentration levels and they can be used as inputs for models that predict long term emission patterns at a given facility.
The contributions presented in this thesis are three-fold. First, a set of algorithms is proposed for GDM with in-situ sensors. These algorithms are designed for real world environments, where multiple chemical com-pounds are commonly present. The limitations of the sensors are ad-dressed by combining different sensing technologies such as metal oxide sensors and photo ionization detectors. In this way multiple distribution models, one for each identified compound, are generated. Second, the use of emergent gas sensing technologies is explored in the context of GDM. Robot assisted gas tomography, which combines tomographic reconstruc-tion algorithms with a mobile robot equipped with remote sensors is first proposed in this thesis. Third, the feasibility of using mobile robots to monitor methane emissions from landfill sites is evaluated. A proof of concept platform that implements robot assisted gas tomography was developed to inspect large environments in order to estimate gas distribu-tion models. The results of this evaluadistribu-tion show that the algorithms pre-sented in this thesis work represent a major step towards a fully autono-mous robot that can operate in complex, real world environments. Keywords: Mobile Robotics Olfaction, Gas Sensors, Gas Discrimination, Gas Distribution Mapping, Tomography of Gases, Service Robots, Envi-ronmental Monitoring.
Víctor Manuel Hernández Bennetts, School of Science and Technology Örebro University, SE-701 82 Örebro, Sweden, [email protected]