Comprehensive Survey and Analysis of Techniques, Advancements, and Challenges in Video-Based Traffic Surveillance Systems

The challenges inherent in video surveillance are compounded by a several factors, like dynamic lighting conditions, the coordination of object matching, diverse environmental scenarios, the tracking of heterogeneous objects, and coping with fluctuations in object poses, occlusions, and motion blur. This research endeavor aims to undertake a rigorous and in-depth analysis of deep learning- oriented models utilized for object identification and tracking. Emphasizing the development of effective model design methodologies, this study intends to furnish a exhaustive and in-depth analysis of object tracking and identification models within the specific domain of video surveillance

A hardware accelerator for ORB-SLAM

Simultaneous Localization And Mapping (SLAM) is a key component of self-driving cars. We study ORB-SLAM, a SLAM state-of-the-art solution, and develop a hardware accelerator for a critical part of it: ORB feature extraction. The accelerator achieve 8x speedup and 2000x energy consumption reduction

A review on the prospects of mobile manipulators for smart maintenance of railway track

Inspection and repair interventions play vital roles in the asset management of railways. Autonomous mobile manipulators possess considerable potential to replace humans in many hazardous railway track maintenance tasks with high efficiency. This paper investigates the prospects of the use of mobile manipulators in track maintenance tasks. The current state of railway track inspection and repair technologies is initially reviewed, revealing that very few mobile manipulators are in the railways. Of note, the technologies are analytically scrutinized to ascertain advantages, unique capabilities, and potential use in the deployment of mobile manipulators for inspection and repair tasks across various industries. Most mobile manipulators in maintenance use ground robots, while other applications use aerial, underwater, or space robots. Power transmission lines, the nuclear industry, and space are the most extensive application areas. Clearly, the railways infrastructure managers can benefit from the adaptation of best practices from these diversified designs and their broad deployment, leading to enhanced human safety and optimized asset digitalization. A case study is presented to show the potential use of mobile manipulators in railway track maintenance tasks. Moreover, the benefits of the mobile manipulator are discussed based on previous research. Finally, challenges and requirements are reviewed to provide insights into future research

Vision-based traffic monitoring system with hierarchical camera auto-calibration

Texto en inglés.En las últimas décadas, el tráfico, debido al aumento de su volumen y al consiguiente incremento en la demanda de infraestructuras de transporte, se ha convertido en un gran problema en ciudades de casi todo el mundo. Constituye un fenómeno social, económico y medioambiental en el que se encuentra inmersa toda la sociedad, por lo que resulta importante tomarlo como un aspecto clave a mejorar. En esta línea, y para garantizar una movilidad segura, fluida y sostenible, es importante analizar el comportamiento e interacción de los vehículos y peatones en diferentes escenarios. Hasta el momento, esta tarea se ha llevado a cabo de forma limitada por operarios en los centros de control de tráfico. Sin embargo, el avance de la tecnología, sugiere una evolución en la metodología hacia sistemas automáticos de monitorización y control. Este trabajo se inscribe en el marco de los Sistemas Inteligentes de Transporte (ITS), concretamente en el ámbito de la monitorización para la detección y predicción de incidencias (accidentes, maniobras peligrosas, colapsos, etc.) en zonas críticas de infraestructuras de tráfico, como rotondas o intersecciones. Para ello se propone el enfoque de la visión artificial, con el objetivo de diseñar un sistema sensor compuesto de una cámara, capaz de medir de forma robusta parámetros correspondientes a peatones y vehículos que proporcionen información a un futuro sistema de detección de incidencias, control de tráfico, etc.El problema general de la visión artificial en este tipo de aplicaciones, y que es donde se hace hincapié en la solución propuesta, es la adaptabilidad del algoritmo a cualquier condición externa. De esta forma, cambios en la iluminación o en la meteorología, inestabilidades debido a viento o vibraciones, oclusiones, etc. son compensadas. Además el funcionamiento es independiente de la posición de la cámara, con la posibilidad de utilizar modelos con pan-tilt-zoom variable para aumentar la versatilidad del sistema. Una de las aportaciones de esta tesis es la extracción y uso de puntos de fuga (a partir de elementos estructurados de la escena), para obtener una calibración de la cámara sin conocimiento previo. Esta calibración proporciona un tamaño aproximado de los objetos buscados, mejorando así el rendimiento de las siguientes etapas del algoritmo. Para segmentar la imagen se realiza una extracción de los objetos móviles a partir del modelado del fondo, basándose en mezcla de Gaussianas (GMM) y métodos de detección de sombras. En cuanto al seguimiento de los objetos segmentados, se desecha la idea tradicional de considerarlos un conjunto. Para ello se extraen características cuya evolución es analizada para conseguir finalmente una agrupación óptima que sea capaz de solventar oclusiones. El sistema ha sido probado en condiciones de tráfico real sin ningún conocimiento previo de la escena, con resultados bastante satisfactorios que muestran la viabilidad del método

Vulnerable road users and connected autonomous vehicles interaction: a survey

There is a group of users within the vehicular traffic ecosystem known as Vulnerable Road Users (VRUs). VRUs include pedestrians, cyclists, motorcyclists, among others. On the other hand, connected autonomous vehicles (CAVs) are a set of technologies that combines, on the one hand, communication technologies to stay always ubiquitous connected, and on the other hand, automated technologies to assist or replace the human driver during the driving process. Autonomous vehicles are being visualized as a viable alternative to solve road accidents providing a general safe environment for all the users on the road specifically to the most vulnerable. One of the problems facing autonomous vehicles is to generate mechanisms that facilitate their integration not only within the mobility environment, but also into the road society in a safe and efficient way. In this paper, we analyze and discuss how this integration can take place, reviewing the work that has been developed in recent years in each of the stages of the vehicle-human interaction, analyzing the challenges of vulnerable users and proposing solutions that contribute to solving these challenges.This work was partially funded by the Ministry of Economy, Industry, and Competitiveness of Spain under Grant: Supervision of drone fleet and optimization of commercial operations flight plans, PID2020-116377RB-C21.Peer ReviewedPostprint (published version

A non-contact vision-based system for multi-point displacement monitoring in a cable-stayed footbridge

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.Vision-based monitoring receives increased attention for measuring displacements of civil infrastructure such as towers and bridges. Currently, most field applications rely on artificial targets for video processing convenience, leading to high installation effort and focus on only single-point displacement measurement e.g. at mid-span of a bridge. This study proposes a low-cost and non-contact vision-based system for multi-point displacement measurement based on a consumer-grade camera for video acquisition and a custom-developed package for video processing. The system has been validated on a cable-stayed footbridge for deck deformation and cable vibration measurement under pedestrian loading. The analysis results indicate that the system provides valuable information about bridge deformation of the order of a few cm induced, in this application, by pedestrian passing. The measured data enables accurate estimation of modal frequencies of either the bridge deck or the bridge cables and could be used to investigate variations of modal frequencies under varying pedestrian loads