Quantitative evaluation of overlaying discrepancies in mobile augmented reality applications for AEC/FM

Augmented Reality (AR) is a trending technology that provides a live view of the real and physical environment augmented by virtual elements, enhancing the information of the scene with digital information (sound, video, graphics, text or geo-location). Its application to architecture, engineering and construction, and facility management (AEC/FM) is straightforward and can be very useful to improve the on-site work at different stages of the projects. However, one of the most important limitations of Mobile Augmented Reality (MAR) is the lack of accuracy when the screen overlays the virtual models on the real images captured by the camera. The main reasons are errors related to tracking (positioning and orientation of the mobile device) and image capture and processing (projection and distortion issues). This paper shows a new methodology to mathematically perform a quantitative evaluation, in world coordinates, of those overlaying discrepancies on the screen, obtaining the real-scale distances from any real point to the sightlines of its virtual projections for any AR application. Additionally, a new utility for filtering built-in sensor signals in mobile devices is presented: the Drift-Vibration-Threshold function (DVT), a straightforward tool to filter the drift suffered by most sensor-based tracking systems

Vehicle positioning by means of radar and its representation through extended reality

¿Tienen las infraestructuras lineales de transporte elementos significativos que puedan constituir una “firma-huella digital” de la propia infraestructura? ¿Pueden detectarse mediante radares y constituir una base para el posicionamiento del vehículo? ¿Cuál sería la representación en una interfaz gráfica 2D o 3D de esa huella digital? ¿Se podría sincronizar esta señal radar con el procesador de una máquina tipo PC ? El autor, a través de esta tesis de carácter industrial, traslada estas cuestiones al ámbito de investigación universitaria y, con la ayuda del grupo de investigación EGICAD de la Universidad de Cantabria, elabora una serie de ensayos y una metodología para dar respuesta a estas cuestiones.Do linear transport infrastructures have significant elements that can constitute a "signature-fingerprint"? Can they be detected by radar and form a basis-system for vehicle positioning? What would be the representation in a 2D or 3D graphical interface of that fingerprint? Could this radar signal be synchronized with the processor of a PC-type machine? The author, through this industrial thesis, transfers these issues to the field of university research and, with the help of the EGICAD research group of the University of Cantabria, elaborates a series of essays and a methodology to answer these question

New methods and functionalities for railway maintenance through a draisine prototype based on RADAR sensors

Abstract Inspection of the railway tracks requires relying on a precise positioning system that accurately determines the location of potential failures and deficiencies. Therefore, measuring the speed and precise location of rail vehicles is essential. Many methods and approaches have been proposed, but most of them lack several conditions that do not allow them to be optimal for this task. In this paper, the authors present a novel method for measuring the speed of a train by means of the time correlation approach, by using 2‐mm wave radar sensors. Additionally, it is also an accurate positioning system because the authors prove that the track has a unique profile, sufficiently characteristic and stable over time, that serves as a distinctive signature, which can be used to locate the vehicle at any point on that track. As a result, this new methodology, combined with a laser profilometer device, can be used as an effective inspection system for cracks or deficiencies in the rails, sleepers, fastenings, bolts etc., locating them precisely on the railway track