669 research outputs found

    The Special Case of Sea Mines

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    In this chapter, work carried out at the Royal Military Academy regarding sea mines and mine countermeasures is summarized. Three sensors used for the detection and identification of sea mines are studied here: sonar, gradiometer and infrared camera. These sensors can be applied to detect different types of sea mines. Some signal and image processing techniques developed to extract relevant information for the detection of underwater objects are presented in this chapter. These techniques are validated using data collected in the frame of different European and NATO projects

    Application of Multi-Sensor Fusion Technology in Target Detection and Recognition

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    Application of multi-sensor fusion technology has drawn a lot of industrial and academic interest in recent years. The multi-sensor fusion methods are widely used in many applications, such as autonomous systems, remote sensing, video surveillance, and the military. These methods can obtain the complementary properties of targets by considering multiple sensors. On the other hand, they can achieve a detailed environment description and accurate detection of interest targets based on the information from different sensors.This book collects novel developments in the field of multi-sensor, multi-source, and multi-process information fusion. Articles are expected to emphasize one or more of the three facets: architectures, algorithms, and applications. Published papers dealing with fundamental theoretical analyses, as well as those demonstrating their application to real-world problems

    Proceedings of the 2011 Joint Workshop of Fraunhofer IOSB and Institute for Anthropomatics, Vision and Fusion Laboratory

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    This book is a collection of 15 reviewed technical reports summarizing the presentations at the 2011 Joint Workshop of Fraunhofer IOSB and Institute for Anthropomatics, Vision and Fusion Laboratory. The covered topics include image processing, optical signal processing, visual inspection, pattern recognition and classification, human-machine interaction, world and situation modeling, autonomous system localization and mapping, information fusion, and trust propagation in sensor networks

    Offshore oil spill detection using synthetic aperture radar

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    Among the different types of marine pollution, oil spill has been considered as a major threat to the sea ecosystems. The source of the oil pollution can be located on the mainland or directly at sea. The sources of oil pollution at sea are discharges coming from ships, offshore platforms or natural seepage from sea bed. Oil pollution from sea-based sources can be accidental or deliberate. Different sensors to detect and monitor oil spills could be onboard vessels, aircraft, or satellites. Vessels equipped with specialised radars, can detect oil at sea but they can cover a very limited area. One of the established ways to monitor sea-based oil pollution is the use of satellites equipped with Synthetic Aperture Radar (SAR).The aim of the work presented in this thesis is to identify optimum set of feature extracted parameters and implement methods at various stages for oil spill detection from Synthetic Aperture Radar (SAR) imagery. More than 200 images of ERS-2, ENVSAT and RADARSAT 2 SAR sensor have been used to assess proposed feature vector for oil spill detection methodology, which involves three stages: segmentation for dark spot detection, feature extraction and classification of feature vector. Unfortunately oil spill is not only the phenomenon that can create a dark spot in SAR imagery. There are several others meteorological and oceanographic and wind induced phenomena which may lead to a dark spot in SAR imagery. Therefore, these dark objects also appear similar to the dark spot due to oil spill and are called as look-alikes. These look-alikes thus cause difficulty in detecting oil spill spots as their primary characteristic similar to oil spill spots. To get over this difficulty, feature extraction becomes important; a stage which may involve selection of appropriate feature extraction parameters. The main objective of this dissertation is to identify the optimum feature vector in order to segregate oil spill and ‘look-alike’ spots. A total of 44 Feature extracted parameters have been studied. For segmentation, four methods; based on edge detection, adaptive theresholding, artificial neural network (ANN) segmentation and the other on contrast split segmentation have been implemented. Spot features are extracted from both the dark spots themselves and their surroundings. Classification stage was performed using two different classification techniques, first one is based on ANN and the other based on a two-stage processing that combines classification tree analysis and fuzzy logic. A modified feature vector, including both new and improved features, is suggested for better description of different types of dark spots. An ANN classifier using full spectrum of feature parameters has also been developed and evaluated. The implemented methodology appears promising in detecting dark spots and discriminating oil spills from look-alikes and processing time is well below any operational service requirements

    Hardware dedicado para sistemas empotrados de visión

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    La constante evolución de las Tecnologías de la Información y las Comunicaciones no solo ha permitido que más de la mitad de la población mundial esté actualmente interconectada a través de Internet, sino que ha sido el caldo de cultivo en el que han surgido nuevos paradigmas, como el ‘Internet de las cosas’ (IoT) o la ‘Inteligencia ambiental’ (AmI), que plantean la necesidad de interconectar objetos con distintas funcionalidades para lograr un entorno digital, sensible y adaptativo, que proporcione servicios de muy distinta índole a sus usuarios. La consecución de este entorno requiere el desarrollo de dispositivos electrónicos de bajo coste que, con tamaño y peso reducido, sean capaces de interactuar con el medio que los rodea, operar con máxima autonomía y proporcionar un elevado nivel de inteligencia. La funcionalidad de muchos de estos dispositivos incluirá la capacidad para adquirir, procesar y transmitir imágenes, extrayendo, interpretando o modificando la información visual que resulte de interés para una determinada aplicación. En el marco de este desafío surge la presente Tesis Doctoral, cuyo eje central es el desarrollo de hardware dedicado para la implementación de algoritmos de procesamiento de imágenes y secuencias de vídeo usados en sistemas empotrados de visión. El trabajo persigue una doble finalidad. Por una parte, la búsqueda de soluciones que, por sus prestaciones y rendimiento, puedan ser incorporadas en sistemas que satisfagan las estrictas exigencias de funcionalidad, tamaño, consumo de energía y velocidad de operación demandadas por las nuevas aplicaciones. Por otra, el diseño de una serie de bloques funcionales implementados como módulos de propiedad intelectual, que permitan aliviar la carga computacional de las unidades de procesado de los sistemas en los que se integren. En la Tesis se proponen soluciones específicas para la implementación de dos tipos de operaciones habitualmente presentes en muchos sistemas de visión artificial: la sustracción de fondo y el etiquetado de componentes conexos. Las distintas alternativas surgen como consecuencia de aplicar una adecuada relación de compromiso entre funcionalidad y coste, entendiendo este último criterio en términos de recursos de cómputo, velocidad de operación y potencia consumida, lo que permite cubrir un amplio espectro de aplicaciones. En algunas de las soluciones propuestas se han utilizado además, técnicas de inferencia basadas en Lógica Difusa con idea de mejorar la calidad de los sistemas de visión resultantes. Para la realización de los diferentes bloques funcionales se ha seguido una metodología de diseño basada en modelos, que ha permitido la realización de todo el ciclo de desarrollo en un único entorno de trabajo. Dicho entorno combina herramientas informáticas que facilitan las etapas de codificación algorítmica, diseño de circuitos, implementación física y verificación funcional y temporal de las distintas alternativas, acelerando con ello todas las fases del flujo de diseño y posibilitando una exploración más eficiente del espacio de posibles soluciones. Asimismo, con el objetivo de demostrar la funcionalidad de las distintas aportaciones de esta Tesis Doctoral, algunas de las soluciones propuestas han sido integradas en sistemas de vídeo reales, que emplean buses estándares de uso común. Los dispositivos seleccionados para llevar a cabo estos demostradores han sido FPGAs y SoPCs de Xilinx, ya que sus excelentes propiedades para el prototipado y la construcción de sistemas que combinan componentes software y hardware, los convierten en candidatos ideales para dar soporte a la implementación de este tipo de sistemas.The continuous evolution of the Information and Communication Technologies (ICT), not only has allowed more than half of the global population to be currently interconnected through Internet, but it has also been the breeding ground for new paradigms such as Internet of Things (ioT) or Ambient Intelligence (AmI). These paradigms expose the need of interconnecting elements with different functionalities in order to achieve a digital, sensitive, adaptive and responsive environment that provides services of distinct nature to the users. The development of low cost devices, with small size, light weight and a high level of autonomy, processing power and ability for interaction is required to obtain this environment. Attending to this last feature, many of these devices will include the capacity to acquire, process and transmit images, extracting, interpreting and modifying the visual information that could be of interest for a certain application. This PhD Thesis, focused on the development of dedicated hardware for the implementation of image and video processing algorithms used in embedded systems, attempts to response to this challenge. The work has a two-fold purpose: on one hand, the search of solutions that, for its performance and properties, could be integrated on systems with strict requirements of functionality, size, power consumption and speed of operation; on the other hand, the design of a set of blocks that, packaged and implemented as IP-modules, allow to alleviate the computational load of the processing units of the systems where they could be integrated. In this Thesis, specific solutions for the implementation of two kinds of usual operations in many computer vision systems are provided. These operations are background subtraction and connected component labelling. Different solutions are created as the result of applying a good performance/cost trade-off (approaching this last criteria in terms of area, speed and consumed power), able to cover a wide range of applications. Inference techniques based on Fuzzy Logic have been applied to some of the proposed solutions in order to improve the quality of the resulting systems. To obtain the mentioned solutions, a model based-design methodology has been applied. This fact has allowed us to carry out all the design flow from a single work environment. That environment combines CAD tools that facilitate the stages of code programming, circuit design, physical implementation and functional and temporal verification of the different algorithms, thus accelerating the overall processes and making it possible to explore the space of solutions. Moreover, aiming to demonstrate the functionality of this PhD Thesis’s contributions, some of the proposed solutions have been integrated on real video systems that employ common and standard buses. The devices selected to perform these demonstrators have been FPGA and SoPCs (manufactured by Xilinx) since, due to their excellent properties for prototyping and creating systems that combine software and hardware components, they are ideal to develop these applications

    Feature-based object tracking in maritime scenes.

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    A monitoring of presence, location and activity of various objects on the sea is essential for maritime navigation and collision avoidance. Mariners normally rely on two complementary methods of the monitoring: radar and satellite-based aids and human observation. Though radar aids are relatively accurate at long distances, their capability of detecting small, unmanned or non-metallic craft that generally do not reflect radar waves sufficiently enough, is limited. The mariners, therefore, rely in such cases on visual observations. The visual observation is often facilitated by using cameras overlooking the sea that can also provide intensified infra-red images. These systems or nevertheless merely enhance the image and the burden of the tedious and error-prone monitoring task still rests with the operator. This thesis addresses the drawbacks of both methods by presenting a framework consisting of a set of machine vision algorithms that facilitate the monitoring tasks in maritime environment. The framework detects and tracks objects in a sequence of images captured by a camera mounted either on a board of a vessel or on a static platform over-looking the sea. The detection of objects is independent of their appearance and conditions such as weather and time of the day. The output of the framework consists of locations and motions of all detected objects with respect to a fixed point in the scene. All values are estimated in real-world units, i. e. location is expressed in metres and velocity in knots. The consistency of the estimates is maintained by compensating for spurious effects such as vibration of the camera. In addition, the framework continuously checks for predefined events such as collision threats or area intrusions, raising an alarm when any such event occurs. The development and evaluation of the framework is based on sequences captured under conditions corresponding to a designated application. The independence of the detection and tracking on the appearance of the sceneand objects is confirmed by a final cross-validation of the framework on previously unused sequences. Potential applications of the framework in various areas of maritime environment including navigation, security, surveillance and others are outlined. Limitations to the presented framework are identified and possible solutions suggested. The thesis concludes with suggestions to further directions of the research presented

    Video based vehicle detection for advance warning Intelligent Transportation System

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    Video based vehicle detection and surveillance technologies are an integral part of Intelligent Transportation System (ITS), due to its non-intrusiveness and capability or capturing global and specific vehicle behavior data. The initial goal of this thesis is to develop an efficient advance warning ITS system for detection of congestion at work zones and special events based on video detection. The goals accomplished by this thesis are: (1) successfully developed the advance warning ITS system using off-the-shelf components and, (2) Develop and evaluate an improved vehicle detection and tracking algorithm. The advance warning ITS system developed includes many off-the-shelf equipments like Autoscope (video based vehicle detector), Digital Video Recorders, RF transceivers, high gain Yagi antennas, variable message signs and interface processors. The video based detection system used requires calibration and fine tuning of configuration parameters for accurate results. Therefore, an in-house video based vehicle detection system was developed using the Corner Harris algorithm to eliminate the need of complex calibration and contrasts modifications. The algorithm was implemented using OpenCV library on a Arcom\u27s Olympus Windows XP Embedded development kit running WinXPE operating system. The algorithm performance is for accuracy in vehicle speed and count is evaluated. The performance of the proposed algorithm is equivalent or better to the Autoscope system without any modifications to calibration and lamination adjustments

    Contributions to improve the technologies supporting unmanned aircraft operations

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    Mención Internacional en el título de doctorUnmanned Aerial Vehicles (UAVs), in their smaller versions known as drones, are becoming increasingly important in today's societies. The systems that make them up present a multitude of challenges, of which error can be considered the common denominator. The perception of the environment is measured by sensors that have errors, the models that interpret the information and/or define behaviors are approximations of the world and therefore also have errors. Explaining error allows extending the limits of deterministic models to address real-world problems. The performance of the technologies embedded in drones depends on our ability to understand, model, and control the error of the systems that integrate them, as well as new technologies that may emerge. Flight controllers integrate various subsystems that are generally dependent on other systems. One example is the guidance systems. These systems provide the engine's propulsion controller with the necessary information to accomplish a desired mission. For this purpose, the flight controller is made up of a control law for the guidance system that reacts to the information perceived by the perception and navigation systems. The error of any of the subsystems propagates through the ecosystem of the controller, so the study of each of them is essential. On the other hand, among the strategies for error control are state-space estimators, where the Kalman filter has been a great ally of engineers since its appearance in the 1960s. Kalman filters are at the heart of information fusion systems, minimizing the error covariance of the system and allowing the measured states to be filtered and estimated in the absence of observations. State Space Models (SSM) are developed based on a set of hypotheses for modeling the world. Among the assumptions are that the models of the world must be linear, Markovian, and that the error of their models must be Gaussian. In general, systems are not linear, so linearization are performed on models that are already approximations of the world. In other cases, the noise to be controlled is not Gaussian, but it is approximated to that distribution in order to be able to deal with it. On the other hand, many systems are not Markovian, i.e., their states do not depend only on the previous state, but there are other dependencies that state space models cannot handle. This thesis deals a collection of studies in which error is formulated and reduced. First, the error in a computer vision-based precision landing system is studied, then estimation and filtering problems from the deep learning approach are addressed. Finally, classification concepts with deep learning over trajectories are studied. The first case of the collection xviiistudies the consequences of error propagation in a machine vision-based precision landing system. This paper proposes a set of strategies to reduce the impact on the guidance system, and ultimately reduce the error. The next two studies approach the estimation and filtering problem from the deep learning approach, where error is a function to be minimized by learning. The last case of the collection deals with a trajectory classification problem with real data. This work completes the two main fields in deep learning, regression and classification, where the error is considered as a probability function of class membership.Los vehículos aéreos no tripulados (UAV) en sus versiones de pequeño tamaño conocidos como drones, van tomando protagonismo en las sociedades actuales. Los sistemas que los componen presentan multitud de retos entre los cuales el error se puede considerar como el denominador común. La percepción del entorno se mide mediante sensores que tienen error, los modelos que interpretan la información y/o definen comportamientos son aproximaciones del mundo y por consiguiente también presentan error. Explicar el error permite extender los límites de los modelos deterministas para abordar problemas del mundo real. El rendimiento de las tecnologías embarcadas en los drones, dependen de nuestra capacidad de comprender, modelar y controlar el error de los sistemas que los integran, así como de las nuevas tecnologías que puedan surgir. Los controladores de vuelo integran diferentes subsistemas los cuales generalmente son dependientes de otros sistemas. Un caso de esta situación son los sistemas de guiado. Estos sistemas son los encargados de proporcionar al controlador de los motores información necesaria para cumplir con una misión deseada. Para ello se componen de una ley de control de guiado que reacciona a la información percibida por los sistemas de percepción y navegación. El error de cualquiera de estos sistemas se propaga por el ecosistema del controlador siendo vital su estudio. Por otro lado, entre las estrategias para abordar el control del error se encuentran los estimadores en espacios de estados, donde el filtro de Kalman desde su aparición en los años 60, ha sido y continúa siendo un gran aliado para los ingenieros. Los filtros de Kalman son el corazón de los sistemas de fusión de información, los cuales minimizan la covarianza del error del sistema, permitiendo filtrar los estados medidos y estimarlos cuando no se tienen observaciones. Los modelos de espacios de estados se desarrollan en base a un conjunto de hipótesis para modelar el mundo. Entre las hipótesis se encuentra que los modelos del mundo han de ser lineales, markovianos y que el error de sus modelos ha de ser gaussiano. Generalmente los sistemas no son lineales por lo que se realizan linealizaciones sobre modelos que a su vez ya son aproximaciones del mundo. En otros casos el ruido que se desea controlar no es gaussiano, pero se aproxima a esta distribución para poder abordarlo. Por otro lado, multitud de sistemas no son markovianos, es decir, sus estados no solo dependen del estado anterior, sino que existen otras dependencias que los modelos de espacio de estados no son capaces de abordar. Esta tesis aborda un compendio de estudios sobre los que se formula y reduce el error. En primer lugar, se estudia el error en un sistema de aterrizaje de precisión basado en visión por computador. Después se plantean problemas de estimación y filtrado desde la aproximación del aprendizaje profundo. Por último, se estudian los conceptos de clasificación con aprendizaje profundo sobre trayectorias. El primer caso del compendio estudia las consecuencias de la propagación del error de un sistema de aterrizaje de precisión basado en visión artificial. En este trabajo se propone un conjunto de estrategias para reducir el impacto sobre el sistema de guiado, y en última instancia reducir el error. Los siguientes dos estudios abordan el problema de estimación y filtrado desde la perspectiva del aprendizaje profundo, donde el error es una función que minimizar mediante aprendizaje. El último caso del compendio aborda un problema de clasificación de trayectorias con datos reales. Con este trabajo se completan los dos campos principales en aprendizaje profundo, regresión y clasificación, donde se plantea el error como una función de probabilidad de pertenencia a una clase.I would like to thank the Ministry of Science and Innovation for granting me the funding with reference PRE2018-086793, associated to the project TEC2017-88048-C2-2-R, which provide me the opportunity to carry out all my PhD. activities, including completing an international research internship.Programa de Doctorado en Ciencia y Tecnología Informática por la Universidad Carlos III de MadridPresidente: Antonio Berlanga de Jesús.- Secretario: Daniel Arias Medina.- Vocal: Alejandro Martínez Cav
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