Seamless Positioning and Navigation in Urban Environment

L'abstract è presente nell'allegato / the abstract is in the attachmen

DEVELOPMENT OF AN AUTONOMOUS NAVIGATION SYSTEM FOR THE SHUTTLE CAR IN UNDERGROUND ROOM & PILLAR COAL MINES

In recent years, autonomous solutions in the multi-disciplinary field of the mining engineering have been an extremely popular applied research topic. The growing demand for mineral supplies combined with the steady decline in the available surface reserves has driven the mining industry to mine deeper underground deposits. These deposits are difficult to access, and the environment may be hazardous to mine personnel (e.g., increased heat, difficult ventilation conditions, etc.). Moreover, current mining methods expose the miners to numerous occupational hazards such as working in the proximity of heavy mining equipment, possible roof falls, as well as noise and dust. As a result, the mining industry, in its efforts to modernize and advance its methods and techniques, is one of the many industries that has turned to autonomous systems. Vehicle automation in such complex working environments can play a critical role in improving worker safety and mine productivity. One of the most time-consuming tasks of the mining cycle is the transportation of the extracted ore from the face to the main haulage facility or to surface processing facilities. Although conveyor belts have long been the autonomous transportation means of choice, there are still many cases where a discrete transportation system is needed to transport materials from the face to the main haulage system. The current dissertation presents the development of a navigation system for an autonomous shuttle car (ASC) in underground room and pillar coal mines. By introducing autonomous shuttle cars, the operator can be relocated from the dusty, noisy, and potentially dangerous environment of the underground mine to the safer location of a control room. This dissertation focuses on the development and testing of an autonomous navigation system for an underground room and pillar coal mine. A simplified relative localization system which determines the location of the vehicle relatively to salient features derived from on-board 2D LiDAR scans was developed for a semi-autonomous laboratory-scale shuttle car prototype. This simplified relative localization system is heavily dependent on and at the same time leverages the room and pillar geometry. Instead of keeping track of a global position of the vehicle relatively to a fixed coordinates frame, the proposed custom localization technique requires information regarding only the immediate surroundings. The followed approach enables the prototype to navigate around the pillars in real-time using a deterministic Finite-State Machine which models the behavior of the vehicle in the room and pillar mine with only a few states. Also, a user centered GUI has been developed that allows for a human user to control and monitor the autonomous vehicle by implementing the proposed navigation system. Experimental tests have been conducted in a mock mine in order to evaluate the performance of the developed system. A number of different scenarios simulating common missions that a shuttle car needs to undertake in a room and pillar mine. The results show a minimum success ratio of 70%

Millimeter-Wave Massive MU-MIMO Performance Analysis for Private Underground Mine Communications

In this article, a performance analysis of millimeter wave (mmWave) massive multiuser multiple-input and multiple-output (MU-MIMO) channel within an underground mine is performed. The analysis is based on channel measurements conducted at 28 GHz using a base station of 64 virtual antenna elements serving multiple users. Channel characteristics such as large-scale path loss, time dispersion, coherence bandwidth and sum-rate capacity are reported and evaluated. The results indicate that multislope path loss model is better suited for precise prediction of path loss across various propagation segments within the mining gallery. The time dispersion analysis reveals that the underground mine channel does not cause significant time dispersion, as 90% of the root-mean-square (rms) delay spreads are below 4 ns. In addition, it was found that the rms delay spread is not dependent on the propagation distance. The study on sum-rate capacity highlights the potential of employing massive MIMO technology to improve the channel’s spectral efficiency. The analysis reveals that the capacity, with eight active users, can reach up to 33.54 bit/s/Hz. The outcomes of this article offer valuable insights into the propagation properties of underground mine environment, which is characterized by rich-scattering and irregular topology

Information technology applications in construction safety assurance

Through analysis of articles published from 2006 to July 2014 this paper summarizes the topics of research and the institutions where research was conducted in the field of computer-based construction safety engineering management. One hundred and thirty-six articles published during this time focused on Information Technology (IT) applications in this field were selected for analysis. The underlying research topics and their related IT implementations are discussed, and research trends in allied specialties are identified

Min Metall Explor

Given the recent focus on powered haulage incidents within the US mining sector, an appraisal of collision avoidance/warning systems (CXSs) through the lens of the available research literature is timely. This paper describes a rapid review that identifies, characterizes, and classifies the research literature to evaluate the maturity of CXS technology through the application of a Technology Readiness Assessment. Systematic search methods were applied to three electronic databases, and relevant articles were identified through the application of inclusion and exclusion criteria. Sixty-four articles from 2000 to 2020 met these criteria and were categorized into seven CXS technology categories. Review and assessment of the articles indicates that much of the literature-based evidence for CXS technology lies within lower levels of maturity (i.e., components and prototypes tested under laboratory conditions and in relevant environments). However, less evidence exists for CXS technology at higher levels of maturity (i.e., complete systems evaluated within operational environments) despite the existence of commercial products in the marketplace. This lack of evidence at higher maturity levels within the scientific literature highlights the need for systematic peer-reviewed research to evaluate the performance of CXS technologies and demonstrate the efficacy of prototypes or commercial products, which could be fostered by more collaboration between academia, research institutions, manufacturers, and mining companies. Additionally, results of the review reveal that most of the literature relevant to CXS technologies is focused on vehicle-to-vehicle interactions. However, this contrasts with haul truck fatal accident statistics that indicate that most haul truck fatal accidents are due to vehicle-to-environment interactions (e.g., traveling through a berm). Lastly, the relatively small amount of literature and segmented nature of the included studies suggests that there is a need for incremental progress or more stepwise research that would facilitate the improvement of CXS technologies over time. This progression over time could be achieved through continued long-term interest and support for CXS technology research.CC999999/ImCDC/Intramural CDC HHSUnited States

Étude et positionnement utilisant le réseau de capteur sans fil dans un environnement minier souterrain

La sécurité et la communication posent des problèmes majeurs auxquels il faut remédier dans les environnements hostiles comme les mines souterraines. Pour une communication fiable ainsi que pour tracer la position exacte d’un objet dans les mines souterraines, différentes technologies ont été déployé. Parmi ces dernières, le réseau de capteurs sans fil est considéré comme un outil prometteur pour les applications basées sur la localisation, à savoir, la surveillance des lieux, le repérage des mobiles et la navigation. En fait, les réseaux de capteur sans-fil fournissent une couverture d’une vaste gamme d’équipements fiables, efficaces, tolérants aux défaillances et évolutives. Cependant, les travaux de recherches précédents ont divisé la localisation en deux parties: les méthodes basées sur la portée et celles non-basées sur la portée. Où la première est précise et coûteuse tandis que la deuxième est présentée pour réduire la quantité d’énergie consommée du côté capteur dont les ressources sont limitées. Notre recherche se focalise sur la localisation basée sur la portée utilisant le réseau de capteurs sans fil dans les milieux internes et mines souterrains. Plusieurs techniques ont été proposées pour la localisation comme la réception de l'indicateur de force de signal (RSSI), le temps d'arrivée (TOA), la différence de temps d'arrivée (TDOA), l'angle d'arrivée (AOA). Bien que plusieurs travaux de recherches utilisant ces techniques aient été exécutés, l'approche de localisation à base de temps pour les environnements complexe comme la mine souterraine demeure limitée. Cette thèse offre de nouvelles solutions pour combler l’écart entre la localisation à base de temps et le réseau de capteurs sans fil à haute précision, pour l’environnement minier souterrain. De plus, nous avons utilisé une technologie émergente, à savoir les communications ultra-large bande, pour booster la performance et l'exactitude. Notre travail de recherche est subdivisé en deux principales parties : une partie simulation et une partie pratique. Dans la première, nous avons utilisé MATLAB pour faire les différentes simulations. La deuxième partie consiste en plusieurs mesures pratiques réalisées dans un environnement intérieur ainsi que dans une mine souterraine. Les résultats montrent une amélioration remarquable et une meilleure précision de la technique UWB à base de temps

Internet of Things-aided Smart Grid: Technologies, Architectures, Applications, Prototypes, and Future Research Directions

Traditional power grids are being transformed into Smart Grids (SGs) to address the issues in existing power system due to uni-directional information flow, energy wastage, growing energy demand, reliability and security. SGs offer bi-directional energy flow between service providers and consumers, involving power generation, transmission, distribution and utilization systems. SGs employ various devices for the monitoring, analysis and control of the grid, deployed at power plants, distribution centers and in consumers' premises in a very large number. Hence, an SG requires connectivity, automation and the tracking of such devices. This is achieved with the help of Internet of Things (IoT). IoT helps SG systems to support various network functions throughout the generation, transmission, distribution and consumption of energy by incorporating IoT devices (such as sensors, actuators and smart meters), as well as by providing the connectivity, automation and tracking for such devices. In this paper, we provide a comprehensive survey on IoT-aided SG systems, which includes the existing architectures, applications and prototypes of IoT-aided SG systems. This survey also highlights the open issues, challenges and future research directions for IoT-aided SG systems