Investigation of wireless electrification for a reconfigurable manufacturing cell

Reconfigurable manufacturing systems (RMS) with a rearrangeable structure can quickly adjust their productivity to meet the dynamic market changes and the demand for high-variety products. Industry 4.0 technologies have enhanced the RMS flexibility and made the automation of the reconfiguration of the manufacturing system possible. As an Industry 4.0 technology, wireless power transfer (WPT) can further increase the flexibility of RMS by providing safe, reliable, and maintenance-free autonomous charging. This paper examines the wireless electrification of RMS by investigating different WPT configurations that increase flexibility and autonomy, creating a highly flexible RMS. It also proposes a battery charging platform for further enhancement of the flexibility of RMS. As a low-cost WPT solution, the paper tests capacitive charging systems. The proposed charging system has about 135 W power transfer capability at a 5 cm distance and about 84% efficiency

Autonomous robot systems and competitions: proceedings of the 12th International Conference

This is the 2012’s edition of the scientific meeting of the Portuguese Robotics Open (ROBOTICA’ 2012). It aims to disseminate scientific contributions and to promote discussion of theories, methods and experiences in areas of relevance to Autonomous Robotics and Robotic Competitions. All accepted contributions are included in this proceedings book. The conference program has also included an invited talk by Dr.ir. Raymond H. Cuijpers, from the Department of Human Technology Interaction of Eindhoven University of Technology, Netherlands.The conference is kindly sponsored by the IEEE Portugal Section / IEEE RAS ChapterSPR-Sociedade Portuguesa de Robótic

Selection of critical nodes in drone airways graphs via graph neural networks

This Master Thesis has two distinct parts. The first one mod- els an application of Graph Neural Networks (GNN) for the identifica- tion of critical nodes in graphs that correspond to traffic networks. We call critical nodes those that can compromise the traffic flow in some subgraphs of the network. Specifically, the example data for the demon- stration corresponds to the Vienna subway network, hence the linear subgraphs correspond to the subway lines with intersections at some key subway stations. Those critical nodes relative to a subway line compro- mise the traffic flow at this line, therefore, we propose three GNN based approaches for the identification of such critical nodes, reporting encour- aging results. The second part of the Master Thesis illustrates the back- ground research work on drone airspace management and a discussion of how the reported results may have some relevance for this emerging dif- ficult problem. The main idea is that the urban airspace for drones, that may be carrying out delivery of either persons (aerotaxis) or goods, can be structured along airways that mimic the existing network of streets. The computational example explored in part one of the Master Thesis, thus, becomes relevant for the development of intelligent drone airspace management

Ultra-wideband Based Indoor Localization of Mobile Nodes in ToA and TDoA Configurations

Zandian R. Ultra-wideband Based Indoor Localization of Mobile Nodes in ToA and TDoA Configurations. Bielefeld: Universität Bielefeld; 2019.This thesis discusses the utilization of ultra-wideband (UWB) technology in indoor localization scenarios and proposes system setup and evaluates different localization algorithms in order to improve the localization accuracy and stability of such systems in non-ideal conditions of the indoor environment. Recent developments and advances of technology in the areas of ubiquitous Internet, robotics and internet of things (IoT) have resulted in emerging new application areas in daily life in which localization systems are vital. The significant demand for a robust and accurate localization system that is applicable in indoor areas lacking satellites link, can be sensed. The UWB technology offers accurate localization systems with an accuracy of below 10 cm and covering the range of up to a few hundred meters thanks to their dedicated large bandwidth, modulation technique and signal power. In this thesis, the technology behind the UWB systems is discussed in detail. In terms of localization topologies, different scenarios with the focus on time-based methods are introduced. The main focus of this thesis is on the differential time of arrival localization systems (TDoA) with unilateral constellation that is suitable for robotic localization and navigation applications. A new approach for synchronization of TDoA topology is proposed and influence of clock inaccuracies in such systems are thoroughly evaluated. For localization engine, two groups of static and dynamic iterative algorithms are introduced. Among the possible dynamic methods, extended Kalman filter (EKF), H∞ and unscented Kalman filter (UKF) are discussed and meticulously evaluated. In order to tackle the non-line of sight (NLOS) problem of such systems, for detection stage several solutions which are based on parametric machine learning methods are proposed. Furthermore, for mitigation phase two solutions namely adjustment of measurement variance and innovation term are suggested. Practical results prove the efficiency and high reliability of the proposed algorithms with positive NLOS condition detection rate of more than 87%. In practical trials, the localization system is evaluated in indoor and outdoor arenas in both line of sight and non-line of sight conditions. The results show that the proposed detection and mitigation methods can be successfully applied for both small and large-scale arenas with the higher performance of the localization filters in terms of accuracy in large-scale scenarios