Underground Mining Monitoring and Communication Systems based on ZigBee and GIS

ZigBee as a wireless sensor network (WSN) was developed for underground mine monitoring and communication systems. The radio wave attenuations between ZigBee nodes were investigated to measure underground communication distances. Various sensor node arrangements of ZigBee topologies were evaluated. A system integration of a WSN-assisted GIS for underground mining monitoring and communication from a surface office was proposed. The controllable and uncontrollable parameters of underground environments were assessed to establish a reliable ZigBee network

Analysis, evaluation and improvement of RT-WMP for real-time and QoS wireless communication: Applications in confined environments

En los ultimos años, la innovación tecnológica, la característica de flexibilidad y el rápido despligue de las redes inalámbricas, han favorecido la difusión de la redes móviles ad-hoc (MANETs), capaces de ofrecer servicios para tareas específicas entre nodos móviles. Los aspectos relacionados al dinamismo de la topología móvil y el acceso a un medio compartido por naturaleza hacen que sea preciso enfrentarse a clases de problemas distintos de los relacionados con la redes cableadas, atrayendo de este modo el interés de la comunidad científica. Las redes ad-hoc suelen soportar tráfico con garantía de servicio mínimo y la mayor parte de las propuestas presentes en literatura tratan de dar garantías de ancho de banda o minimizar el retardo de los mensajes. Sin embargo hay situaciones en las que estas garantías no son suficientes. Este es el caso de los sistemas que requieren garantías mas fuertes en la entrega de los mensajes, como es el caso de los sistemas de tiempo real donde la pérdida o el retraso de un sólo mensaje puede provocar problemas graves. Otras aplicaciones como la videoconferencia, cada vez más extendidas, implican un tráfico de datos con requisitos diferentes, como la calidad de servicio (QoS). Los requisitos de tiempo real y de QoS añaden nuevos retos al ya exigente servicio de comunicación inalámbrica entre estaciones móviles de una MANET. Además, hay aplicaciones en las que hay que tener en cuenta algo más que el simple encaminamiento de los mensajes. Este es el caso de aplicaciones en entornos subterráneos, donde el conocimiento de la evolución de propagación de la señal entre los diferentes nodos puede ser útil para mejorar la calidad de servicio y mantener la conectividad en cada momento. A pesar de ésto, dentro del amplio abanicos de propuestas presente en la literatura, existen un conjunto de limitaciones que van de el mero uso de protocolos simulados a propuestas que no tienen en cuenta entornos no convencionales o que resultan aisladas desde el punto de vista de la integración en sistemas complejos. En esta tesis doctoral, se propone un estudio completo sobre un plataforma inalámbrica de tiempo real, utilizando el protocolo RT-WMP capaz de gestionar trafíco multimedia al mismo tiempo y adaptado al entorno de trabajo. Se propone una extensión para el soporte a los datos con calidad de servicio sin limitar las caractaristícas temporales del protocolo básico. Y con el fin de tener en cuenta el efecto de la propagación de la señal, se caracteriza el entorno por medio de un conjunto de restricciones de conectividad. La solución ha sido desarrollada y su validez ha sido demostrada extensamente en aplicaciones reales en entornos subterráneos, en redes malladas y aplicaciones robóticas

Wireless Sensor Networks for Condition Monitoring in the Railway Industry : a Survey

In recent years, the range of sensing technologies has expanded rapidly, whereas sensor devices have become cheaper. This has led to a rapid expansion in condition monitoring of systems, structures, vehicles, and machinery using sensors. Key factors are the recent advances in networking technologies such as wireless communication and mobile adhoc networking coupled with the technology to integrate devices. Wireless sensor networks (WSNs) can be used for monitoring the railway infrastructure such as bridges, rail tracks, track beds, and track equipment along with vehicle health monitoring such as chassis, bogies, wheels, and wagons. Condition monitoring reduces human inspection requirements through automated monitoring, reduces maintenance through detecting faults before they escalate, and improves safety and reliability. This is vital for the development, upgrading, and expansion of railway networks. This paper surveys these wireless sensors network technology for monitoring in the railway industry for analyzing systems, structures, vehicles, and machinery. This paper focuses on practical engineering solutions, principally,which sensor devices are used and what they are used for; and the identification of sensor configurations and network topologies. It identifies their respective motivations and distinguishes their advantages and disadvantages in a comparative review

Flexible Supervised Autonomy for Exploration in Subterranean Environments

While the capabilities of autonomous systems have been steadily improving in recent years, these systems still struggle to rapidly explore previously unknown environments without the aid of GPS-assisted navigation. The DARPA Subterranean (SubT) Challenge aimed to fast track the development of autonomous exploration systems by evaluating their performance in real-world underground search-and-rescue scenarios. Subterranean environments present a plethora of challenges for robotic systems, such as limited communications, complex topology, visually-degraded sensing, and harsh terrain. The presented solution enables long-term autonomy with minimal human supervision by combining a powerful and independent single-agent autonomy stack, with higher level mission management operating over a flexible mesh network. The autonomy suite deployed on quadruped and wheeled robots was fully independent, freeing the human supervision to loosely supervise the mission and make high-impact strategic decisions. We also discuss lessons learned from fielding our system at the SubT Final Event, relating to vehicle versatility, system adaptability, and re-configurable communications.Comment: Field Robotics special issue: DARPA Subterranean Challenge, Advancement and Lessons Learned from the Final

Concept and design of the hybrid distributed embedded systems testbed

Wireless mesh networks are an emerging and versatile communication technology. The most common application of these networks is to provide access of any number of users to the world wide Internet. They can be set up by Internet service providers or even individuals joined in communities. Due to the wireless medium that is shared by all participants, effects like short-time fading, or the multi-hop property of the network topology many issues are still in the focus of research. Testbeds are a powerful tool to study wireless mesh networks as close as possible to real world application scenarios. In this technical report we describe the design, architecture, and implementation of our work-in-progress wireless testbed at Freie Universität Berlin consisting of 100 mesh routers that span multiple buildings. The testbed is hybrid as it combines wireless mesh network routers with a wireless sensor network

Towards self-powered wireless sensor networks

Ubiquitous computing aims at creating smart environments in which computational and communication capabilities permeate the word at all scales, improving the human experience and quality of life in a totally unobtrusive yet completely reliable manner. According to this vision, an huge variety of smart devices and products (e.g., wireless sensor nodes, mobile phones, cameras, sensors, home appliances and industrial machines) are interconnected to realize a network of distributed agents that continuously collect, process, share and transport information. The impact of such technologies in our everyday life is expected to be massive, as it will enable innovative applications that will profoundly change the world around us. Remotely monitoring the conditions of patients and elderly people inside hospitals and at home, preventing catastrophic failures of buildings and critical structures, realizing smart cities with sustainable management of traffic and automatic monitoring of pollution levels, early detecting earthquake and forest fires, monitoring water quality and detecting water leakages, preventing landslides and avalanches are just some examples of life-enhancing applications made possible by smart ubiquitous computing systems. To turn this vision into a reality, however, new raising challenges have to be addressed, overcoming the limits that currently prevent the pervasive deployment of smart devices that are long lasting, trusted, and fully autonomous. In particular, the most critical factor currently limiting the realization of ubiquitous computing is energy provisioning. In fact, embedded devices are typically powered by short-lived batteries that severely affect their lifespan and reliability, often requiring expensive and invasive maintenance. In this PhD thesis, we investigate the use of energy-harvesting techniques to overcome the energy bottleneck problem suffered by embedded devices, particularly focusing on Wireless Sensor Networks (WSNs), which are one of the key enablers of pervasive computing systems. Energy harvesting allows to use energy readily available from the environment (e.g., from solar light, wind, body movements, etc.) to significantly extend the typical lifetime of low-power devices, enabling ubiquitous computing systems that can last virtually forever. However, the design challenges posed both at the hardware and at the software levels by the design of energy-autonomous devices are many. This thesis addresses some of the most challenging problems of this emerging research area, such as devising mechanisms for energy prediction and management, improving the efficiency of the energy scavenging process, developing protocols for harvesting-aware resource allocation, and providing solutions that enable robust and reliable security support. %, including the design of mechanisms for energy prediction and management, improving the efficiency of the energy harvesting process, the develop of protocols for harvesting-aware resource allocation, and providing solutions that enable robust and reliable security support

Improving Resilience of Transport Instrastructure to Climate Change and other natural and Manmande events based on the combined use of Terrestrial and Airbone Sensors and Advanced Modelling Tools

The project PANOPTIS, funded by the European Commission under the H2020 Programme, aims at increasing the resilience of the transport infrastructures (focusing on roads) and ensuring reliable network availability under unfavourable conditions, such as extreme weather, landslides, and earthquakes. The main target is to combine downscaled climate change scenarios (applied to road infrastructures) with structural and geotechnical simulation tools and with actual data from a multi-sensor network (terrestrial and airborne-based), so as to provide the operators with an integrated tool able to support more effective management of their infrastructures at planning, maintenance and operation level. During the first stage of the project, the consortium will develop advanced technologies to monitor and control transport infrastructures, such as a Geotechnical and Structural Simulation Tool (SGSA) to predict structural and geotechnical risks in road infrastructures; drone-technologies applied to road upkeep and incident management; improved computer vision and machine learning techniques for damage diagnosis of infrastructure, and early warning systems to help operators identify and communicate emerging systemic risks. At the same time, experts in climate modelling, will analyse the possible short and long term effects of climate change on transport infrastructure (e.g. flooding, heavier snows). All the information from the different sensors, models and applications will be integrated and processed through a unique Resilience Assessment Platform that will support operators in the introduction of adaptation and mitigation strategies based on multi-risk scenarios. During the second stage of the project, ACCIONA Engineering will implement the developed technologies and methodologies in a section of the Spanish A-2 motorway, in the province of Guadalajara. PANOPTIS integrated Platform will help optimize the management and maintenance of the Ministry of Public Works' concession for a 77.5-km section, all in collaboration with ACCIONA Infrastructure Maintenance (AMISA) and ACCIONA Concessions. In parallel, PANOPTIS platform will also be implemented in a section of 62 Km of a Greek motorway, renowned for its seismic activity. The trials in Greece hosted by the operator Egnatia Odos will integrate the motorway that serves the Airport of Thessaloniki. So the scenario will integrate a modal transfer segment.Le projet PANOPTIS, financé par la Commission européenne dans le cadre du programme H2020, vise à accroître la résilience de l'infrastructure de transport et à permettre une disponibilité fiable du réseau dans des conditions défavorables, telles que les conditions météorologiques extrêmes, les glissements de terrain et les tremblements de terre. L'objectif principal doit être associé à un réseau multi-capteurs (terrestre et aéroporté) pour permettre une gestion plus efficace de leurs infrastructures au niveau de la planification, de la maintenance et de l'exploitation. Au cours de la première phase du projet, le consortium développera des technologies avancées pour surveiller et contrôler les infrastructures de transport, telles que l'outil de simulation géotechnique et structurelle (SGSA) permettant de prévoir les risques structurels et géotechniques dans les infrastructures routières; technologies de drones appliquées à l'entretien des routes et à la gestion des incidents; la vision par ordinateur et les techniques d'apprentissage automatique pour le diagnostic des infrastructures et les systèmes d'alerte précoce. Dans le même temps, des experts en modélisation du climat analyseront le potentiel du changement climatique sur les infrastructures de transport (par exemple, les inondations, les neiges plus lourdes). Toutes les informations provenant des différents capteurs, modèles et applications seront intégrées dans un scénario unique comportant plusieurs risques. Au cours de la deuxième phase du projet, ACCIONA Engineering mettra en oeuvre les technologies et les méthodologies dans une section de l'autoroute espagnole A-2, dans la province de Guadalajara. La plate-forme intégrée PANOPTIS contribuera à optimiser la gestion et la maintenance de la concession du ministère des Travaux publics pour une section de 77,5 km, le tout en collaboration avec ACCIONA Infrastructure Maintenance (AMISA) et ACCIONA Concessions. Parallèlement, la plate-forme PANOPTIS sera également mise en oeuvre dans une section de 62 Km d'une autoroute grecque réputée pour son activité sismique. Les essais en Grèce organisés par l'opérateur Egnatia Odos vont rejoindre l'aéroport de Thessalonique. Le scénario intégrera donc un segment de transfert modal