47 resultados para Automotive vehicles

em Universidad Politécnica de Madrid


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Speech Technologies can provide important benefits for the development of more usable and safe in-vehicle human-machine interactive systems (HMIs). However mainly due robustness issues, the use of spoken interaction can entail important distractions to the driver. In this challenging scenario, while speech technologies are evolving, further research is necessary to explore how they can be complemented with both other modalities (multimodality) and information from the increasing number of available sensors (context-awareness). The perceived quality of speech technologies can significantly be increased by implementing such policies, which simply try to make the best use of all the available resources; and the in vehicle scenario is an excellent test-bed for this kind of initiatives. In this contribution we propose an event-based HMI design framework which combines context modelling and multimodal interaction using a W3C XML language known as SCXML. SCXML provides a general process control mechanism that is being considered by W3C to improve both voice interaction (VoiceXML) and multimodal interaction (MMI). In our approach we try to anticipate and extend these initiatives presenting a flexible SCXML-based approach for the design of a wide range of multimodal context-aware HMI in-vehicle interfaces. The proposed framework for HMI design and specification has been implemented in an automotive OSGi service platform, and it is being used and tested in the Spanish research project MARTA for the development of several in-vehicle interactive applications.

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During the past years, the industry has shifted position and moved towards “the luxury universe” whose customers are demanding, treating individuals as unique and valued customer for the business, offering vehicles produced with the state of the art technologies and implementing the highest finishing standards. Due to the competitive level in the market, car makers enable processes which equalizes customer services to E.R. management, being dealt with the maximum urgency that allows the comparison between both, car workshops and emergency rooms, where workshop bays or ramps will be equal to emergency boxes and skilled technicians are equivalent to the health care specialist, who will carry out tests and checks prior to afford any final operation, keeping the “patient” under control before it is back to normal utilization. This paper establishes a valid model for the automotive industry to estimate customer service demand forecasting under variable demand conditions using analogies with patient demand models used for the medical ER.

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En esta tesis se aborda la detección y el seguimiento automático de vehículos mediante técnicas de visión artificial con una cámara monocular embarcada. Este problema ha suscitado un gran interés por parte de la industria automovilística y de la comunidad científica ya que supone el primer paso en aras de la ayuda a la conducción, la prevención de accidentes y, en última instancia, la conducción automática. A pesar de que se le ha dedicado mucho esfuerzo en los últimos años, de momento no se ha encontrado ninguna solución completamente satisfactoria y por lo tanto continúa siendo un tema de investigación abierto. Los principales problemas que plantean la detección y seguimiento mediante visión artificial son la gran variabilidad entre vehículos, un fondo que cambia dinámicamente debido al movimiento de la cámara, y la necesidad de operar en tiempo real. En este contexto, esta tesis propone un marco unificado para la detección y seguimiento de vehículos que afronta los problemas descritos mediante un enfoque estadístico. El marco se compone de tres grandes bloques, i.e., generación de hipótesis, verificación de hipótesis, y seguimiento de vehículos, que se llevan a cabo de manera secuencial. No obstante, se potencia el intercambio de información entre los diferentes bloques con objeto de obtener el máximo grado posible de adaptación a cambios en el entorno y de reducir el coste computacional. Para abordar la primera tarea de generación de hipótesis, se proponen dos métodos complementarios basados respectivamente en el análisis de la apariencia y la geometría de la escena. Para ello resulta especialmente interesante el uso de un dominio transformado en el que se elimina la perspectiva de la imagen original, puesto que este dominio permite una búsqueda rápida dentro de la imagen y por tanto una generación eficiente de hipótesis de localización de los vehículos. Los candidatos finales se obtienen por medio de un marco colaborativo entre el dominio original y el dominio transformado. Para la verificación de hipótesis se adopta un método de aprendizaje supervisado. Así, se evalúan algunos de los métodos de extracción de características más populares y se proponen nuevos descriptores con arreglo al conocimiento de la apariencia de los vehículos. Para evaluar la efectividad en la tarea de clasificación de estos descriptores, y dado que no existen bases de datos públicas que se adapten al problema descrito, se ha generado una nueva base de datos sobre la que se han realizado pruebas masivas. Finalmente, se presenta una metodología para la fusión de los diferentes clasificadores y se plantea una discusión sobre las combinaciones que ofrecen los mejores resultados. El núcleo del marco propuesto está constituido por un método Bayesiano de seguimiento basado en filtros de partículas. Se plantean contribuciones en los tres elementos fundamentales de estos filtros: el algoritmo de inferencia, el modelo dinámico y el modelo de observación. En concreto, se propone el uso de un método de muestreo basado en MCMC que evita el elevado coste computacional de los filtros de partículas tradicionales y por consiguiente permite que el modelado conjunto de múltiples vehículos sea computacionalmente viable. Por otra parte, el dominio transformado mencionado anteriormente permite la definición de un modelo dinámico de velocidad constante ya que se preserva el movimiento suave de los vehículos en autopistas. Por último, se propone un modelo de observación que integra diferentes características. En particular, además de la apariencia de los vehículos, el modelo tiene en cuenta también toda la información recibida de los bloques de procesamiento previos. El método propuesto se ejecuta en tiempo real en un ordenador de propósito general y da unos resultados sobresalientes en comparación con los métodos tradicionales. ABSTRACT This thesis addresses on-road vehicle detection and tracking with a monocular vision system. This problem has attracted the attention of the automotive industry and the research community as it is the first step for driver assistance and collision avoidance systems and for eventual autonomous driving. Although many effort has been devoted to address it in recent years, no satisfactory solution has yet been devised and thus it is an active research issue. The main challenges for vision-based vehicle detection and tracking are the high variability among vehicles, the dynamically changing background due to camera motion and the real-time processing requirement. In this thesis, a unified approach using statistical methods is presented for vehicle detection and tracking that tackles these issues. The approach is divided into three primary tasks, i.e., vehicle hypothesis generation, hypothesis verification, and vehicle tracking, which are performed sequentially. Nevertheless, the exchange of information between processing blocks is fostered so that the maximum degree of adaptation to changes in the environment can be achieved and the computational cost is alleviated. Two complementary strategies are proposed to address the first task, i.e., hypothesis generation, based respectively on appearance and geometry analysis. To this end, the use of a rectified domain in which the perspective is removed from the original image is especially interesting, as it allows for fast image scanning and coarse hypothesis generation. The final vehicle candidates are produced using a collaborative framework between the original and the rectified domains. A supervised classification strategy is adopted for the verification of the hypothesized vehicle locations. In particular, state-of-the-art methods for feature extraction are evaluated and new descriptors are proposed by exploiting the knowledge on vehicle appearance. Due to the lack of appropriate public databases, a new database is generated and the classification performance of the descriptors is extensively tested on it. Finally, a methodology for the fusion of the different classifiers is presented and the best combinations are discussed. The core of the proposed approach is a Bayesian tracking framework using particle filters. Contributions are made on its three key elements: the inference algorithm, the dynamic model and the observation model. In particular, the use of a Markov chain Monte Carlo method is proposed for sampling, which circumvents the exponential complexity increase of traditional particle filters thus making joint multiple vehicle tracking affordable. On the other hand, the aforementioned rectified domain allows for the definition of a constant-velocity dynamic model since it preserves the smooth motion of vehicles in highways. Finally, a multiple-cue observation model is proposed that not only accounts for vehicle appearance but also integrates the available information from the analysis in the previous blocks. The proposed approach is proven to run near real-time in a general purpose PC and to deliver outstanding results compared to traditional methods.

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This article presents a novel system and a control strategy for visual following of a 3D moving object by an Unmanned Aerial Vehicle UAV. The presented strategy is based only on the visual information given by an adaptive tracking method based on the color information, which jointly with the dynamics of a camera fixed to a rotary wind UAV are used to develop an Image-based visual servoing IBVS system. This system is focused on continuously following a 3D moving target object, maintaining it with a fixed distance and centered on the image plane. The algorithm is validated on real flights on outdoors scenarios, showing the robustness of the proposed systems against winds perturbations, illumination and weather changes among others. The obtained results indicate that the proposed algorithms is suitable for complex controls task, such object following and pursuit, flying in formation, as well as their use for indoor navigation

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This work presents a solution for the aerial coverage of a field by using a fleet of aerial vehicles. The use of Unmanned Aerial Vehicles allows to obtain high resolution mosaics to be used in Precision Agriculture techniques. This report is focus on providing a solution for the full simultaneous coverage problem taking into account restrictions as the required spatial resolution and overlap while maintaining similar light conditions and safety operation of the drones. Results obtained from real field tests are finally reported

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In this paper, vehicle-track interaction for a new slab track design, conceived to reduce noise and vibration levels has been analyzed, assessing the derailment risk for trains running on curved track when encountering a broken rail. Two different types of rail fastening systems with different elasticities have been analysed and compared. Numerical methods were used in order to simulate the dynamic behaviour of the train-track interaction. Multibody system (MBS) modelling techniques were combined with techniques based on the finite element method (FEM). MBS modelling was used for modelling the vehicle and FEM for simulating the elastic track. The simulation model was validated by comparing simulated results to experimental data obtained in field testing. During the simulations various safety indices, characteristic of derailment risk, were analysed. The simulations realised at the maximum running velocity of 110 km/h showed a similar behaviour for several track types. When reducing the running speed, the safety indices worsened for both cases. Although the worst behaviour was observed for the track with a greater elasticity, in none of the simulations did a derailment occur when running over the broken rail.

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Vehicle–track interaction for a new resilient slab track designed to reduce noise and vibration levels was analysed, in order to assess the derailment risk on a curved track when encountering a broken rail. Sensitivity of the rail support spacing of the relative position of the rail breakage between two adjacent rail supports and of running speed were analysed for two different elasticities of the rail fastening system. In none of the cases analysed was observed an appreciable difference between either of the elastic systems. As was expected, the most unfavourable situations were those with greater rail support spacing and those with greater distance from the breakage to the nearest rail support, although in none of the simulations performed did a derailment occur when running over the broken rail. When varying the running speed, the most favourable condition was obtained for an intermediate speed, due to the superposition of two antagonistic effects.

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Waste produced during the service life of automobiles has received much less attention than end-of-life vehicles themselves. In this paper, we deal with the set up of a reverse logistics system for the collection and treatment of use-phase residues. First, the type of waste arising during vehicles? service life is characterized. Data were collected in collaboration with SIGRAUTO, the product stewardship organization in charge of vehicles? recovery in Spain. Next, three organizational models are proposed. The three alternatives are benchmarked and assessed from a double organizational and operational perspective for the particular case of the Madrid region in Spain

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In this paper, we seek to expand the use of direct methods in real-time applications by proposing a vision-based strategy for pose estimation of aerial vehicles. The vast majority of approaches make use of features to estimate motion. Conversely, the strategy we propose is based on a MR (Multi-Resolution) implementation of an image registration technique (Inverse Compositional Image Alignment ICIA) using direct methods. An on-board camera in a downwards-looking configuration, and the assumption of planar scenes, are the bases of the algorithm. The motion between frames (rotation and translation) is recovered by decomposing the frame-to-frame homography obtained by the ICIA algorithm applied to a patch that covers around the 80% of the image. When the visual estimation is required (e.g. GPS drop-out), this motion is integrated with the previous known estimation of the vehicles' state, obtained from the on-board sensors (GPS/IMU), and the subsequent estimations are based only on the vision-based motion estimations. The proposed strategy is tested with real flight data in representative stages of a flight: cruise, landing, and take-off, being two of those stages considered critical: take-off and landing. The performance of the pose estimation strategy is analyzed by comparing it with the GPS/IMU estimations. Results show correlation between the visual estimation obtained with the MR-ICIA and the GPS/IMU data, that demonstrate that the visual estimation can be used to provide a good approximation of the vehicle's state when it is required (e.g. GPS drop-outs). In terms of performance, the proposed strategy is able to maintain an estimation of the vehicle's state for more than one minute, at real-time frame rates based, only on visual information.

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During the past years, the industry has shifted position and moved towards “the luxury universe” whose customers are demanding, treating individuals as unique and valued customer for the business, offering vehicles produced with the state of the art technologies and implementing the highest finishing standards. Due to the competitive level in the market, motor makers enable processes which equalizes customer services to E.R. management, being dealt with the maximum urgency that allows the comparison between both, car workshops and emergency rooms, where workshop bays or ramps will be equal to emergency boxes and skilled technicians are equivalent to the health care specialist, who will carry out tests and checks prior to afford any final operation, keeping the “patient” under control before it is back to normal utilization. This paper ratify a valid model for the automotive industry to estimate customer service demand forecasting under variable demand conditions using analogies with patient demand models used for the medical ER

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It is known that the techniques under the topic of Soft Computing have a strong capability of learning and cognition, as well as a good tolerance to uncertainty and imprecision. Due to these properties they can be applied successfully to Intelligent Vehicle Systems; ITS is a broad range of technologies and techniques that hold answers to many transportation problems. The unmannedcontrol of the steering wheel of a vehicle is one of the most important challenges facing researchers in this area. This paper presents a method to adjust automatically a fuzzy controller to manage the steering wheel of a mass-produced vehicle; to reach it, information about the car state while a human driver is handling the car is taken and used to adjust, via iterative geneticalgorithms an appropriated fuzzy controller. To evaluate the obtained controllers, it will be considered the performance obtained in the track following task, as well as the smoothness of the driving carried out.

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This article presents a cartographic system to facilitate cooperative manoeuvres among autonomous vehicles in a well-known environment. The main objective is to design an extended cartographic system to help in the navigation of autonomous vehicles. This system has to allow the vehicles not only to access the reference points needed for navigation, but also noticeable information such as the location and type of traffic signals, the proximity to a crossing, the streets en route, etc. To do this, a hierarchical representation of the information has been chosen, where the information has been stored in two levels. The lower level contains the archives with the Universal Traverse Mercator (UTM) coordinates of the points that define the reference segments to follow. The upper level contains a directed graph with the relational database in which streets, crossings, roundabouts and other points of interest are represented. Using this new system it is possible to know when the vehicle approaches a crossing, what other paths arrive at that crossing, and, should there be other vehicles circulating on those paths and arriving at the crossing, which one has the highest priority. The data obtained from the cartographic system is used by the autonomous vehicles for cooperative manoeuvres.

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Decreasing the accidents on highway and urban environments is the main motivation for the research and developing of driving assistance systems, also called ADAS (Advanced Driver Assistance Systems). In recent years, there are many applications of these systems in commercial vehicles: ABS systems, Cruise Control (CC), parking assistance and warning systems (including GPS), among others. However, the implementation of driving assistance systems on the steering wheel is more limited, because of their complexity and sensitivity. This paper is focused in the development, test and implementation of a driver assistance system for controlling the steering wheel in curve zones. This system is divided in two levels: an inner control loop which permits to execute the position and speed target, softening the action over the steering wheel, and a second control outer loop (controlling for fuzzy logic) that sends the reference to the inner loop according the environment and vehicle conditions. The tests have been done in different curves and speeds. The system has been proved in a commercial vehicle with satisfactory results.

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En los años recientes se ha producido un rápido crecimiento del comercio internacional en productos semielaborados que son diseñados, producidos y ensamblados en diferentes localizaciones a lo largo de diferentes países, debido principalmente a los siguientes motivos: el desarrollo de las tecnologías de la información, la reducción de los costes de transporte, la liberalización de los mercados de capitales, la armonización de factores institucionales, la integración económica regional que implica la reducción y la eliminación de las barreras al comercio, el desarrollo económico de los países emergentes, el uso de economías de escala, así como una desregulación del comercio internacional. Todo ello ha incrementado la competencia a nivel mundial en los mercados y ha posibilitado a las compañías tener más facilidad de acceso a potenciales mercados, así como a la adquisición de capacidades y conocimientos en otros países y a la realización de alianzas estratégicas internacionales con terceros, creando un entorno con mayor incertidumbre y más exigente para las compañías que componen una industria, y que tiene consecuencias directas en las operaciones de las compañías y en la organización de su producción. Las compañías, para adaptarse, ser competitivas y beneficiarse de este nuevo escenario globalizado y más competitivo, han externalizado partes del proceso productivo hacia proveedores especializados, creando un nuevo mercado intermedio que divide el proceso productivo, anteriormente integrado en las compañías que conforman una industria, entre dos conjuntos de empresas especializadas en esa industria. Dicho proceso suele ocurrir conservando la industria en que tiene lugar, los mismos servicios y productos, la tecnología empleada y las compañías originales que la conformaban previamente a la desintegración vertical. Todo ello es así debido a que es beneficioso tanto para las compañías originales de la industria como para las nuevas compañías de este mercado intermedio por diversos motivos. La desintegración vertical en una industria tiene unas consecuencias que la transforman completamente, así como la forma de operar de las compañías que la integran, incluso para aquellas que permanecen verticalmente integradas. Una de las características más importantes de esta desintegración vertical en una industria es la posibilidad que tiene una compañía de adquirir a una tercera la primera parte del proceso productivo o un bien semielaborado, que posteriormente será finalizado por la compañía adquiriente con la práctica del outsourcing; así mismo, una compañía puede realizar la primera parte del proceso productivo o un bien semielaborado, que posteriormente será finalizado por una tercera compañía con la práctica de la fragmentación. El principal objetivo de la presente investigación es el estudio de los motivos, los facilitadores, los efectos, las consecuencias y los principales factores significativos, microeconómicos y macroeconómicos, que desencadenan o incrementan la práctica de la desintegración vertical en una industria; para ello, la investigación se divide en dos líneas completamente diferenciadas: el estudio de la práctica del outsourcing y, por otro lado, el estudio de la fragmentación por parte de las compañías que componen la industria del automóvil en España, puesto que se trata de una de las industrias más desintegradas verticalmente y fragmentadas, y este sector posee una gran importancia en la economía del país. En primer lugar, se hace una revisión de la literatura existente relativa a los siguientes aspectos: desintegración vertical, outsourcing, fragmentación, teoría del comercio internacional, historia de la industria del automóvil en España y el uso de las aglomeraciones geográficas y las tecnologías de la información en el sector del automóvil. La metodología empleada en cada uno de ellos ha sido diferente en función de la disponibilidad de los datos y del enfoque de investigación: los factores microeconómicos, utilizando el outsourcing, y los factores macroeconómicos, empleando la fragmentación. En el estudio del outsourcing, se usa un índice basado en las compras externas sobre el valor total de la producción. Así mismo, se estudia su correlación y significación con las variables económicas más importantes que definen a una compañía del sector del automóvil, utilizando la técnica estadística de regresión lineal. Aquellas variables relacionadas con la competencia en el mercado, la externalización de las actividades de menor valor añadido y el incremento de la modularización de las actividades de la cadena de valor, han resultado significativas con la práctica del outsourcing. En el estudio de la fragmentación se seleccionan un conjunto de factores macroeconómicos, comúnmente usados en este tipo de investigaciones, relacionados con las principales magnitudes económicas de un país, y un conjunto de factores macroeconómicos, no comúnmente usados en este tipo de investigaciones, relacionados con la libertad económica y el comercio internacional de un país. Se emplea un modelo de regresión logística para identificar qué factores son significativos en la práctica de la fragmentación. De entre todos los factores usados en el modelo, los relacionados con las economías de escala y los costes de servicio han resultado significativos. Los resultados obtenidos de los test estadísticos realizados en el modelo de regresión logística han resultado satisfactorios; por ello, el modelo propuesto de regresión logística puede ser considerado sólido, fiable y versátil; además, acorde con la realidad. De los resultados obtenidos en el estudio del outsourcing y de la fragmentación, combinados conjuntamente con el estado del arte, se concluye que el principal factor que desencadena la desintegración vertical en la industria del automóvil es la competencia en el mercado de vehículos. Cuanto mayor es la demanda de vehículos, más se reducen los beneficios y la rentabilidad para sus fabricantes. Estos, para ser competitivos, diferencian sus productos de la competencia centrándose en las actividades que mayor valor añadido aportan al producto final, externalizando las actividades de menor valor añadido a proveedores especializados, e incrementando la modularidad de las actividades de la cadena de valor. Las compañías de la industria del automóvil se especializan en alguna o varias de estas actividades modularizadas que, combinadas con el uso de factores facilitadores como las economías de escala, las tecnologías de la información, las ventajas de la globalización económica y la aglomeración geográfica de una industria, incrementan y motivan la desintegración vertical en la industria del automóvil, desencadenando la coespecialización en dos sectores claramente diferenciados: el sector de fabricantes de vehículos y el sector de proveedores especializados. Cada uno de ellos se especializa en unas actividades y en unos productos o servicios específicos de la cadena de valor, lo cual genera las siguientes consecuencias en la industria del automóvil: se reducen los costes de transacción en los productos o servicios intercambiados; se incrementan la relación de dependencia entre fabricantes de vehículos y proveedores especializados, provocando un aumento en la cooperación y la coordinación, acelerando el proceso de aprendizaje, posibilitando a ambos adquirir nuevas capacidades, conocimientos y recursos, y creando nuevas ventajas competitivas para ambos; por último, las barreras de entrada a la industria del automóvil y el número de compañías se ven alteradas cambiando su estructura. Como futura línea de investigación, los fabricantes de vehículos tenderán a centrarse en investigar, diseñar y comercializar el producto o servicio, delegando el ensamblaje en manos de nuevos especialistas en la materia, el contract manufacturer; por ello, sería conveniente investigar qué factores motivantes o facilitadores existen y qué consecuencias tendría la implantación de los contract manufacturer en la industria del automóvil. 1.1. ABSTRACT In recent years there has been a rapid growth of international trade in semi-finished products designed, produced and assembled in different locations across different countries, mainly due to the following reasons: development of information technologies, reduction of transportation costs, liberalisation of capital markets, harmonisation of institutional factors, regional economic integration, which involves the reduction and elimination of trade barriers, economic development of emerging countries, use of economies of scale and deregulation of international trade. All these factors have increased competition in markets at a global level and have allowed companies to gain easier access to potential markets and to the acquisition of skills and knowledge in other countries, as well as to the completion of international strategic alliances with third parties, thus creating a more demanding and uncertain environment for these companies constituting an industry, which has a direct impact on the companies' operations and the organization of their production. In order to adapt, be competitive and benefit from this new and more competitive global scenario, companies have outsourced some parts of their production process to specialist suppliers, generating a new intermediate market which divides the production process, previously integrated in the companies that made up the industry, into two sets of companies specialized in that industry. This process often occurs while preserving the industry where it takes place, its same services and products, the technology used and the original companies that formed it prior to vertical disintegration. This is because it is beneficial for both the industry's original companies and the companies belonging to this new intermediate market, for various reasons. Vertical disintegration has consequences which completely transform the industry where it takes place as well as the modus operandi of the companies that are part of it, even of those who remain vertically integrated. One of the most important features of vertical disintegration of an industry is the possibility for a company to acquire from a third one the first part of the production process or a semi-finished product, which will then be finished by the acquiring company through the practice of outsourcing; also, a company can perform the first part of the production process or a semi-finish product, which will then be completed by a third company through the practice of fragmentation. The main objective of this research is to study the motives, facilitators, effects, consequences and major significant microeconomic and macroeconomic factors that trigger or increase the practice of vertical disintegration in a certain industry; in order to do so, research is divided into two completely differentiated lines: on the one hand, the study of the practise of outsourcing and, on the other, the study of fragmentation by companies constituting the automotive industry in Spain, since this is one of the most vertically disintegrated and fragmented industries and this particular sector is of major significance in this country's economy. First, a review is made of the existing literature, on the following aspects: vertical disintegration, outsourcing, fragmentation, international trade theory, history of the automobile industry in Spain and the use of geographical agglomeration and information technologies in the automotive sector. The methodology used for each of these aspects has been different depending on the availability of data and the research approach: the microeconomic factors, using outsourcing, and the macroeconomic factors, using fragmentation. In the study on outsourcing, an index is used based on external purchases in relation to the total value of production. Likewise, their significance and correlation with the major economic variables that define an automotive company are studied, using the statistical technique of linear regression. Variables related to market competition, outsourcing of lowest value-added activities and increased modularisation of the activities of the value chain have turned out to be significant with the practice of outsourcing. In the study of fragmentation, a set of macroeconomic factors commonly used for this type of research, is selected, related to the main economic indicators of a country, as well as a set of macroeconomic factors, not commonly used for this type of research, which are related to economic freedom and the international trade of a certain country. A logistic regression model is used to identify which factors are significant in the practice of fragmentation. Amongst all factors used in the model, those related to economies of scale and service costs have turned out to be significant. The results obtained from the statistical tests performed on the logistic regression model have been successful; hence, the suggested logistic regression model can be considered to be solid, reliable and versatile; likewise, it is in line with reality. From the results obtained in the study of outsourcing and fragmentation, combined with the state of the art, it is concluded that the main factor that triggers vertical disintegration in the automotive industry is competition within the vehicle market. The greater the vehicle demand, the lower the earnings and profitability for manufacturers. These, in order to be competitive, differentiate their products from the competition by focusing on those activities that contribute with the highest added value to the final product, outsourcing the lower valueadded activities to specialist suppliers, and increasing the modularity of the activities of the value chain. Companies in the automotive industry specialize in one or more of these modularised activities which, combined with the use of enabling factors such as economies of scale, information technologies, the advantages of economic globalisation and the geographical agglomeration of an industry, increase and encourage vertical disintegration in the automotive industry, triggering co-specialization in two clearly distinct sectors: the sector of vehicle manufacturers and the specialist suppliers sector. Each of them specializes in certain activities and specific products or services of the value chain, generating the following consequences in the automotive industry: reduction of transaction costs of the goods or services exchanged; growth of the relationship of dependency between vehicle manufacturers and specialist suppliers, which causes an increase in cooperation and coordination, accelerates the learning process, enables both to acquire new skills, knowledge and resources, and creates new competitive advantages for both; finally, barriers to entry the automotive industry and the number of companies are altered, changing their structure. As a future line of research, vehicle manufacturers will tend to focus on researching, designing and marketing the product or service, delegating the assembly in the hands of new specialists in the field, the contract manufacturer; for this reason, it would be useful to investigate what motivating or facilitating factors exist in this respect and what consequences would the implementation of contract manufacturers have in the automotive industry.

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El objetivo principal de esta Tesis es extender la utilización del “Soft- Computing” para el control de vehículos sin piloto utilizando visión. Este trabajo va más allá de los típicos sistemas de control utilizados en entornos altamente controlados, demonstrando la fuerza y versatilidad de la lógica difusa (Fuzzy Logic) para controlar vehículos aéreos y terrestres en un abanico de applicaciones diferentes. Para esta Tesis se ha realizado un gran número de pruebas reales en las cuales los controladores difusos han manejado una plataforma visual “pan-and-tilt”, un helicoptero, un coche comercial y hasta dos tipos de quadrirotores. El uso del método de optimización “Cross-Entropy” ha sido utilizado para mejorar el comportamiento de algunos de los controladores borrosos. Todos los controladores difusos presentados en ésta Tesis han sido implementados utilizando un código desarrollado por el candidato para tal efecto, llamado MOFS (Miguel Olivares’ Fuzzy Software). Diferentes algoritmos visuales han sido utilizados para adquirir la informaci´on visual del entorno, “Cmashift”, descomposición de la homografía y detección de marcas de realidad aumentada, entre otros. Dicha información visual ha sido utilizada como entrada de los controladores difusos para comandar los vehículos en las diferentes applicaciones autonomas. El volante de un vehículo comercial ha sido controlado para realizar pruebas de conducción autónoma en condiciones de tráfico similares a las de una ciudad. El sistema ha llegado a completar con éxito pruebas de más de 6 km sin ninguna interacción humana, mediante el seguimiento de una línea pintada en el suelo. El limitado campo visual del sistema no ha sido impedimento para alcanzar velocidades de hasta 48 km/h y ser guiado autonomamente en curvas de radio reducido. Objetos estáticos y móviles han sido seguidos desde un helicoptero no tripulado, mediante el control de una plataforma visual “pan-and-tilt”. ´Éste mismo helicoptero ha sido controlado completamente para su aterrizaje autonomo, mediante el control del movimiento lateral (roll), horizontal (pitch) y de altitud. El seguimiento de objetos volantes ha sido resulto mediante el control horizontal (pitch) y de orientación (heading) de un quadrirotor. Para tareas de evitación de obstáculos se ha implementado un controlador difuso para el manejo de la orientación (heading) de un quadrirotor. En el campo de la optimización de controladores se ha aportado al estado del arte una extensión del uso del método “Cross-Entropy”. Está Tesis presenta una novedosa implementación de dicho método para la optimización de las ganancias, la posición y medida de los conjuntos de las funciones de pertenecia y el peso de las reglas para mejorar el comportamiento de un controlador difuso. Dichos procesos de optimización se han realizado utilizando “ROS” y “Matlab Simulink” para obtener mejores resultados para la evitación de colisiones con vehículos aéreos no tripulados. Ésta Tesis demuestra que los controladores implementados con lógica difusa son altamente capaces de controlador sistemas sin tener en cuenta el modelo del vehículo a controlador en entornos altamente perturbables con un sensor de bajo coste como es una cámara. El ruido presentes causado por los cambios de iluminación en la adquisición de imágenes y la alta incertidumbre en la detección visual han sido manejados satisfactoriamente por ésta técnica de de “Soft-Computing” para distintas aplicaciones tanto con vehículos aéreos como terrestres.