Co-simulation Methodologies for Hybrid and Electric Vehicle Dynamics

In recent decades, full electric and hybrid electric vehicles have emerged as an alternative to conventional cars due to a range of factors, including environmental and economic aspects. These vehicles are the result of considerable efforts to seek ways of reducing the use of fossil fuel for vehicle propulsion. Sophisticated technologies such as hybrid and electric powertrains require careful study and optimization. Mathematical models play a key role at this point. Currently, many advanced mathematical analysis tools, as well as computer applications have been built for vehicle simulation purposes. Given the great interest of hybrid and electric powertrains, along with the increasing importance of reliable computer-based models, the author decided to integrate both aspects in the research purpose of this work. Furthermore, this is one of the first final degree projects held at the ETSII (Higher Technical School of Industrial Engineers) that covers the study of hybrid and electric propulsion systems. The present project is based on MBS3D 2.0, a specialized software for the dynamic simulation of multibody systems developed at the UPM Institute of Automobile Research (INSIA). Automobiles are a clear example of complex multibody systems, which are present in nearly every field of engineering. The work presented here benefits from the availability of MBS3D software. This program has proven to be a very efficient tool, with a highly developed underlying mathematical formulation. On this basis, the focus of this project is the extension of MBS3D features in order to be able to perform dynamic simulations of hybrid and electric vehicle models. This requires the joint simulation of the mechanical model of the vehicle, together with the model of the hybrid or electric powertrain. These sub-models belong to completely different physical domains. In fact the powertrain consists of energy storage systems, electrical machines and power electronics, connected to purely mechanical components (wheels, suspension, transmission, clutch…). The challenge today is to create a global vehicle model that is valid for computer simulation. Therefore, the main goal of this project is to apply co-simulation methodologies to a comprehensive model of an electric vehicle, where sub-models from different areas of engineering are coupled. The created electric vehicle (EV) model consists of a separately excited DC electric motor, a Li-ion battery pack, a DC/DC chopper converter and a multibody vehicle model. Co-simulation techniques allow car designers to simulate complex vehicle architectures and behaviors, which are usually difficult to implement in a real environment due to safety and/or economic reasons. In addition, multi-domain computational models help to detect the effects of different driving patterns and parameters and improve the models in a fast and effective way. Automotive designers can greatly benefit from a multidisciplinary approach of new hybrid and electric vehicles. In this case, the global electric vehicle model includes an electrical subsystem and a mechanical subsystem. The electrical subsystem consists of three basic components: electric motor, battery pack and power converter. A modular representation is used for building the dynamic model of the vehicle drivetrain. This means that every component of the drivetrain (submodule) is modeled separately and has its own general dynamic model, with clearly defined inputs and outputs. Then, all the particular submodules are assembled according to the drivetrain configuration and, in this way, the power flow across the components is completely determined. Dynamic models of electrical components are often based on equivalent circuits, where Kirchhoff’s voltage and current laws are applied to draw the algebraic and differential equations. Here, Randles circuit is used for dynamic modeling of the battery and the electric motor is modeled through the analysis of the equivalent circuit of a separately excited DC motor, where the power converter is included. The mechanical subsystem is defined by MBS3D equations. These equations consider the position, velocity and acceleration of all the bodies comprising the vehicle multibody system. MBS3D 2.0 is entirely written in MATLAB and the structure of the program has been thoroughly studied and understood by the author. MBS3D software is adapted according to the requirements of the applied co-simulation method. Some of the core functions are modified, such as integrator and graphics, and several auxiliary functions are added in order to compute the mathematical model of the electrical components. By coupling and co-simulating both subsystems, it is possible to evaluate the dynamic interaction among all the components of the drivetrain. ‘Tight-coupling’ method is used to cosimulate the sub-models. This approach integrates all subsystems simultaneously and the results of the integration are exchanged by function-call. This means that the integration is done jointly for the mechanical and the electrical subsystem, under a single integrator and then, the speed of integration is determined by the slower subsystem. Simulations are then used to show the performance of the developed EV model. However, this project focuses more on the validation of the computational and mathematical tool for electric and hybrid vehicle simulation. For this purpose, a detailed study and comparison of different integrators within the MATLAB environment is done. Consequently, the main efforts are directed towards the implementation of co-simulation techniques in MBS3D software. In this regard, it is not intended to create an extremely precise EV model in terms of real vehicle performance, although an acceptable level of accuracy is achieved. The gap between the EV model and the real system is filled, in a way, by introducing the gas and brake pedals input, which reflects the actual driver behavior. This input is included directly in the differential equations of the model, and determines the amount of current provided to the electric motor. For a separately excited DC motor, the rotor current is proportional to the traction torque delivered to the car wheels. Therefore, as it occurs in the case of real vehicle models, the propulsion torque in the mathematical model is controlled through acceleration and brake pedal commands. The designed transmission system also includes a reduction gear that adapts the torque coming for the motor drive and transfers it. The main contribution of this project is, therefore, the implementation of a new calculation path for the wheel torques, based on performance characteristics and outputs of the electric powertrain model. Originally, the wheel traction and braking torques were input to MBS3D through a vector directly computed by the user in a MATLAB script. Now, they are calculated as a function of the motor current which, in turn, depends on the current provided by the battery pack across the DC/DC chopper converter. The motor and battery currents and voltages are the solutions of the electrical ODE (Ordinary Differential Equation) system coupled to the multibody system. Simultaneously, the outputs of MBS3D model are the position, velocity and acceleration of the vehicle at all times. The motor shaft speed is computed from the output vehicle speed considering the wheel radius, the gear reduction ratio and the transmission efficiency. This motor shaft speed, somehow available from MBS3D model, is then introduced in the differential equations corresponding to the electrical subsystem. In this way, MBS3D and the electrical powertrain model are interconnected and both subsystems exchange values resulting as expected with tight-coupling approach.When programming mathematical models of complex systems, code optimization is a key step in the process. A way to improve the overall performance of the integration, making use of C/C++ as an alternative programming language, is described and implemented. Although this entails a higher computational burden, it leads to important advantages regarding cosimulation speed and stability. In order to do this, it is necessary to integrate MATLAB with another integrated development environment (IDE), where C/C++ code can be generated and executed. In this project, C/C++ files are programmed in Microsoft Visual Studio and the interface between both IDEs is created by building C/C++ MEX file functions. These programs contain functions or subroutines that can be dynamically linked and executed from MATLAB. This process achieves reductions in simulation time up to two orders of magnitude. The tests performed with different integrators, also reveal the stiff character of the differential equations corresponding to the electrical subsystem, and allow the improvement of the cosimulation process. When varying the parameters of the integration and/or the initial conditions of the problem, the solutions of the system of equations show better dynamic response and stability, depending on the integrator used. Several integrators, with variable and non-variable step-size, and for stiff and non-stiff problems are applied to the coupled ODE system. Then, the results are analyzed, compared and discussed. From all the above, the project can be divided into four main parts: 1. Creation of the equation-based electric vehicle model; 2. Programming, simulation and adjustment of the electric vehicle model; 3. Application of co-simulation methodologies to MBS3D and the electric powertrain subsystem; and 4. Code optimization and study of different integrators. Additionally, in order to deeply understand the context of the project, the first chapters include an introduction to basic vehicle dynamics, current classification of hybrid and electric vehicles and an explanation of the involved technologies such as brake energy regeneration, electric and non-electric propulsion systems for EVs and HEVs (hybrid electric vehicles) and their control strategies. Later, the problem of dynamic modeling of hybrid and electric vehicles is discussed. The integrated development environment and the simulation tool are also briefly described. The core chapters include an explanation of the major co-simulation methodologies and how they have been programmed and applied to the electric powertrain model together with the multibody system dynamic model. Finally, the last chapters summarize the main results and conclusions of the project and propose further research topics. In conclusion, co-simulation methodologies are applicable within the integrated development environments MATLAB and Visual Studio, and the simulation tool MBS3D 2.0, where equation-based models of multidisciplinary subsystems, consisting of mechanical and electrical components, are coupled and integrated in a very efficient way.

1950 En torno al Museo Louisiana 1970

La tesis “1950 En torno al Museo Louisiana 1970” analiza varias obras relacionadas con el espacio doméstico, que se realizaron entre 1950 y 1970 en Dinamarca, un periodo de esplendor de la Arquitectura Moderna. Tras el aislamiento y restricciones del conflicto bélico que asoló Europa, los jóvenes arquitectos daneses, estaban deseosos por experimentar nuevas ideas de procedencia internacional, favorecidos por diferentes circunstancias, encuentran el mejor campo de ensayo en el espacio doméstico. La mejor arquitectura doméstica en Dinamarca, de aquel periodo, debe entenderse como un sistema compuesto por diferentes autores, que tienen en común muchas más similitudes que diferencias, se complementan unos a otros. Para la comprensión y el entendimiento de ello se hace necesario el estudio de varias figuras y edificios, que completen este sistema cuya investigación está escasamente desarrollada. La tesis propone un viaje para conocer los nombres de algunos de sus protagonistas, que mostraron con su trabajo, que tradición y vanguardia no estarán reñidas. El objetivo es desvelar las claves de la Modernidad Danesa, reconocer, descubrir y recuperar el legado de algunos de sus protagonistas en el ámbito doméstico, cuya lección se considera de total actualidad. Una arquitectura que asume las aportaciones extranjeras con moderación y crítica, cuya íntima relación con la tradición arquitectónica y la artesanía propias, será una de sus notas especiales. Del estudio contrastado de varios proyectos y versiones, se obtienen valores comunes entre sus autores, al igual que se descubren sus afinidades o diferencias respecto a los mismos asuntos; que permitirán comprender sus actuaciones según las referencias e influencias, y definir las variables que configuran sus espacios arquitectónicos. La línea de conexión entre los edificios elegidos será su particular relación con la naturaleza y el lugar en que se integran. La fachada, lugar donde se negociará la relación entre el interior y el paisaje, será un elemento entendido de un modo diferente en cada uno de ellos, una relación que se extenderá en todas ellas, más allá de su perímetro. La investigación se ha estructurado en seis capítulos, que van precedidos de una Introducción. En el capítulo primero, se estudian y se señalan los antecedentes, las figuras y edificios más relevantes de la Tradición Danesa, para la comprensión y el esclarecimiento de algunas de las claves de su Modernidad en el campo de la Arquitectura, que se produce con una clara intención de encontrar su propia identidad y expresión. Esta Modernidad floreciente se caracteriza por la asimilación de otras culturas extranjeras desde la moderación, con un punto de vista crítico, y encuentra sus raíces ancladas a la tradición arquitectónica y la artesanía propia, que fragua en la aparición de un ideal común con enorme personalidad y que hoy se valora como una auténtica aportación de una cultura considerada entonces periférica. Se mostrará el debate y el camino seguido por las generaciones anteriores, a las obras análizadas. Las sensibilidades por lo vernáculo y lo clásico, que aparentemente son contradictorias, dominaran el debate con la misma veracidad y respetabilidad. La llamada tercera generación por Sigfried Giedion reanudará la práctica entre lo clásico y lo vernáculo, apoyados en el espíritu del trabajo artesanal y de la tradición, con el objetivo de conocer del acto arquitectónico su “la verdad” y “la esencia original”. El capítulo segundo, analiza la casa Varming, de 1953, situada en un área residencial de Gentofte, por Eva y Nils Koppel, que reinterpreta la visión de Asplund de un paisaje interior continuación del exterior, donde rompen la caja de ladrillo macizo convencional propia de los años 30. Es el ejemplo más poderoso de la unión de tradición e innovación en su obra residencial. Sus formas sobrias entre el Funcionalismo Danés y la Modernidad se singularizarán por su abstracción y volúmenes limpios que acentúan el efecto de su geometría, prismática y brutalista. El desplazamiento de los cuerpos que lo componen, unos sobre otros, generan un ritmo, que se producirá a otras escalas, ello unido a las variaciones de sus formas y a la elección de sus materiales, ladrillo y madera, le confieren a la casa un carácter orgánico. El edificio se ancla a la tierra resolviéndose en diferentes niveles tras el estudio del lugar y su topografía. El resultado es una versión construida del paisaje, en la cual el edificio da forma al lugar y ensalza la experiencia del escenario natural. La unidad de las estructuras primitivas, parece estar presente. Constituye un ejemplo de la “La idea de Promenade de Asplund”, el proyecto ofrece diferentes recorridos, permitiendo su propia vivencia de la casa, que ofrece la posibilidad vital de decidir. El capítulo tercero trata sobre el pabellón de invitados de Niels Bohr de 1957, situado un área boscosa, en Tisvilde Hegn, fue el primer edificio del arquitecto danés Vilhelm Wohlert. Arraigado a la Tradición Danesa, representa una renovación basada en la absorción de influencias extranjeras: la Arquitectura Americana y la Tradición Japonesa. La caja de madera, posada sobre un terreno horizontal, tiene el carácter sensible de un organismo vivo, siempre cambiante según las variaciones de luz del día o temperatura. Cuando se abre, crea una prolongación del espacio interior, que se extiende a la naturaleza circundante, y se expande hacia el espacio exterior, permitiendo su movilización. Se establece una arquitectura de flujos. Hay un interés por la materia, su textura y el efecto emocional que emana. Las proporciones y dimensiones del edificio están reguladas por un módulo, que se ajusta a la medida del hombre, destacando la gran unidad del edificio. La llave se su efecto estético está en su armonía y equilibrio, que transmiten serenidad y belleza. El encuentro con la naturaleza es la lección más básica del proyecto, donde un mundo de relaciones es amable al ser humano. El capítulo cuarto, analiza el proyecto del Museo Louisiana de 1958, en Humlebæk, primer proyecto de la pareja de arquitectos daneses Jørgen Bo y Vilhelm Wohlert. La experiencia en California de Wohlert donde será visitado por Bo, será trascendental para el desarrollo de Louisiana, donde la identidad Danesa se fusiona con la asimilación de otras culturas, la arquitectura de Frank Lloyd Wright, la del área de la Bahía y la Tradición Japonesa principalmente. La idea del proyecto es la de una obra de arte integral: arquitectura, arte y paisaje, coexistirían en un mismo lugar. Diferentes recursos realzarán su carácter residencial, como el uso de los materiales propios de un entorno doméstico, la realización a la escala del hombre, el modo de usar la iluminación. Cubiertas planas que muestran su artificialidad, parecen flotar sobre galerías acristaladas, acentuarán la fuerza del plano horizontal y establecerán un recorrido en zig-zag de marcado ritmo acompasado. Ritmo que tiene que ver con la encarnación del pulso de la naturaleza, que se acompaña de juegos de luz, y de otras vibraciones materiales a diferentes escalas, imagen, que encuentra una analogía semejante en la cultura japonesa. Todo se coordina con la trama estructural, que conlleva a una construcción y proporción disciplinada. Louisiana atiende al principio de crecimiento de la naturaleza, con la que su conexión es profunda. Hay un dinamismo expresado por el despliegue del edificio, que evoca a algunos proyectos de la Tradición Japonesa. Los blancos muros tienen su propia identidad como formas en sí mismas, avanzan prolongándose fuera de la línea del vidrio, se mueven libremente siguiendo el orden estructural, acompañando al espacio que fluye, en contacto directo con la naturaleza que está en un continuo estado de flujos. Se da todo un mundo de relaciones, donde existe un dialogo entre el paisaje, arte y arquitectura. El capítulo quinto, se dedica a analizar la segunda casa del arquitecto danés Halldor Gunnløgsson, de 1959. Evoca a la Arquitectura Japonesa y Americana, pero es principalmente resultado de una fuerte voluntad y disciplina artística personal. La cubierta, plana, suspendida sobre una gran plataforma pavimentada, que continúa la sección del terreno construyendo de lugar, tiene una gran presencia y arroja una profunda sombra bajo ella. En el interior un espacio único, que se puede dividir eventualmente, discurre en torno a un cuerpo central. El espacio libre fluye, extendiéndose a través de la transparencia de sus ventanales a dos espacios contrapuestos: un patio ajardinado íntimo, que inspira calma y sosiego; y la naturaleza salvaje del mar que proyecta el color del cielo, ambos en constante estado de cambio. El proyecto se elabora de un modo rigurosamente formal, existiendo al mismo tiempo un perfecto equilibrio entre la abstracción de su estructura y su programa. La estructura de madera cuyo orden se extiende más allá de los límites de su perímetro, está formada por pórticos completos como elementos libres, queda expuesta, guardando una estrecha relación con el concepto de modernidad de Mies, equivalente a la arquitectura clásica. La preocupación por el efecto estético es máxima, nada es improvisado. Pero además la combinación de materiales y el juego de las texturas hay una cualidad táctil, cierto erotismo, que flota alrededor de ella. La precisión constructiva y su refinamiento se acercan a Mies. La experiencia del espacio arquitectónico es una vivencia global. La influencia de la arquitectura japonesa, es más conceptual que formal, revelada en un respeto por la naturaleza, la búsqueda del refinamiento a través de la moderación, la eliminación de los objetos innecesarios que distraen de la experiencia del lugar y la preocupación por la luz y la sombra, donde se establece cierto paralelismo con el oscuro mundo del invierno nórdico. Hay un entendimiento de que el espacio, en lugar de ser un objeto inmaterial definido por superficies materiales se entiende como interacciones dinámicas. El capítulo sexto. Propone un viaje para conocer algunas de las viviendas unifamiliares más interesantes que se construyeron en el periodo, que forman parte del sistema investigado. Del estudio comparado y orientado en varios temas, se obtienen diversa conclusiones propias del sistema estudiado. La maestría de la sustancia y la forma será una característica distintiva en Dinamarca, se demuestra que hay un acercamiento a la cultura de Oriente, conceptual y formal, y unos intereses comunes con cierta arquitectura Americana. Su lección nos sensibiliza hacia un sentido fortalecido de proporción, escala, materialidad, textura y peso, densidad del espacio, se valora lo táctil y lo visual, hay una sensibilidad hacia la naturaleza, hacia lo humano, hacia el paisaje, la integridad de la obra. ABSTRACT The thesis “1950 around the Louisiana Museum 1970” analyses several works related to domestic space, which were carried out between 1950 and 1970 in Denmark, a golden age of modern architecture. After the isolation and limitations brought about by the war that blighted Europe, young Danish architects were keen to experiment with ideas of an international origin, encouraged by different circumstances. They find the best field of rehearsal to be the domestic space. The best architecture of that period in Denmark should be understood as a system composed of different authors, who have in common with each other many more similarities than differences, thus complimenting each other. In the interests of understanding, the study of a range of figures and buildings is necessary so that this system, the research of which is still in its infancy, can be completed. The thesis proposes a journey of discovery through the names of some of those protagonists who were showcased through their work so that tradition and avant- garde could go hand in hand. The objective is to unveil the keys to Danish Modernity; to recognise, discover and revive the legacy of some of its protagonists in the domestic field whose lessons are seen as entirely of the present. For an architect, the taking on of modern contributions with both moderation and caution, with its intimate relationship with architectural tradition and its own craft, will be one of his hallmarks. With the study set against several projects and versions, one can derive common values among their authors. In the same way their affinities and differences in respect of the same issue emerge. This will allow an understanding of their measures in line with references and influences and enable the defining of the variables of their architectural spaces. The common line between the buildings selected will be their particular relationship with nature and the space with which they integrate. The façade, the place where the relationship between the interior and the landscape would be negotiated, wouldl be the discriminating element in a distinct way for each one of them. It is through each of these facades that this relationship would extend, and far beyond their physical perimeter. The investigation has been structured into six chapters, preceded by an introduction. The first chapter outlines and analyses the backgrounds, figures and buildings most relevant to the Danish Tradition. This is to facilitate the understanding and elucidation of some of the keys to its modernity in the field of architecture, which came about with the clear intention to discover its own identity and expression. This thriving modernity is characterized by its moderate assimilation with foreign cultures with a critical eye, and finds its roots anchored in architectural tradition and its own handcraft. It is forged in the emergence of a common ideal of enormous personality which today has come to be valued as an authentic contribution to the sphere from a culture that was formerly seen as on the peripheries. What will be demonstrated is the path taken by previous generations to these works and the debate that surrounds them. The sensibilities for both the vernacular and the classic, which at first glance may seem contradictory, will dominate the debate with the same veracity and respectability. The so-called third generation of Sigfried Giedion will revive the process between the classic and the vernacular, supported in spirit by the handcraft work and by tradition, with the objective of discovering the “truth” and the “original essence” of the architectural act. The second chapter analyzes the Varming house, built by Eva and Nils Koppel 1953, which is situated in a residential area of Gentofte. This reinterprets Asplund’s vision of an interior landscape extending to the exterior, where we see a break with the conventional sturdy brick shell of the 1930s. It is the most powerful example of the union of tradition and innovation in his their residential work. Their sober forms caught between Danish Functionalism and modernity are characterized by their abstraction and clean shapes which accentuate their prismatic and brutal geometry, The displacement of the parts of which they are composed, one over the other, generate a rhythm. This is produced to varying scales and is closely linked to its forms and the selection of materials – brick and wood – that confer an organic character to the house. The building is anchored to the earth, finding solution at different levels through the study of place and topography. The result is an adaption constructed out of the landscape, in which the building gives form to the place and celebrates the experience of the natural setting. The unity of primitive structures appears to be present. It constitutes an example of “Asplund’s Promenade Idea”. Different routes of exploration within are available to the visitor, allowing for one’s own personal experience of the house, allowing in turn for the vital chance to decide. The third chapter deals with Niels Bohr’s guest pavilion. Built in 1957, it is situated in a wooded area of Tisvilde Hegn and was the architect Vilhelm Wohlert’s first building. Rooted in the Danish Tradition, it represents a renewal based on the absorption of foreign influences: American architecture and the Japanese tradition. The wooden box, perched atop a horizontal terrain, possesses the sensitive character of the living organism, ever-changing in accordance with the variations in daylight and temperature. When opened up, it creates an elongation of the interior space which extends into the surrounding nature and it expands towards the exterior space, allowing for its mobilisation. It establishes an architecture of flux. There is interest in the material, its texture and the emotional effect it inspires. The building’s proportions and dimensions are regulated by a module, which is adjusted by hand, bringing out the great unity of the building. The key to its aesthetic effect is its harmony and equilibrium, which convey serenity and beauty. The meeting with nature is the most fundamental lesson of the project, where a world of relationships softens the personality of the human being. The fourth chapter analyzes the Louisiana Museum project of 1958 in 1958. It was the first project of the Danish architects Jørgen Bo and Vilhelm Wohlert. Wohlert’s experience in California where he was visited by Bo would be essential to the development of Louisiana, where the Danish identity is fused in assimilation with other cultures, the architecture of Frank Lloyd Wright, that of the Bahía area and principally the Japanese tradition. The idea of the project was for an integrated work of art: architecture, art and landscape, which would coexist in the same space. A range of different resources would realize the residential character, such as the use of materials taken from a domestic environment, the attainment of human scale and the manner in which light was used. Flat roof plans that show their artificiality and appear to float over glassed galleries. They accentuate the strength of the horizontal plan and establish a zigzag route of marked and measured rhythm. It is a rhythm that has to do with the incarnation of nature’s pulse, which is accompanied with plays of light, as well as material vibrations of different scales, imagery which uncovers a parallel analogy with Japanese culture. Everything is coordinated along a structural frame, which involves a disciplined construction and proportion. Louisiana cherishes nature’s principle of growth, to which its connection is profound. Here is a dynamism expressed through the disposition of the building, which evokes in some projects the Japanese tradition. The white walls possess their own identity as forms in their own right. They advance, extending beyond the line of glass, moving freely along the structural line, accompanying a space that flows and in direct contact with nature that is itself in a constant state of flux. It creates a world of relationships, where dialogue exists between the landscape, art and architecture. The fifth chapter is dedicated to analyzing the Danish architect Halldor Gunnløgsson’s second house, built in 1959. It evokes both Japanese and American architecture but is principally the result of a strong will and personal artistic discipline. The flat roof suspended above a large paved platform – itself continuing the constructed terrain of the place – has great presence and casts a heavy shadow beneath. In the interior, a single space, which can at length be divided and which flows around a central space. The space flows freely, extending through the transparency of its windows which give out onto two contrasting locations: an intimate garden patio, inspiring calm and tranquillity, and the wild nature of the sea which projects the colour of sky, both in a constant state of change. The project is realized in a rigorously formal manner. A perfect balance exists between the abstraction of his structure and his project. The wooden structure, whose order extends beyond the limits of its perimeter, is formed of complete porticos of free elements. It remains exposed, maintaining a close relationship with Mies’ concept of modernity, analogous to classical architecture. The preoccupation with the aesthetic effect is paramount and nothing is improvised. But in addition to this - the combination of materials and the play of textures - there is a tactile quality, a certain eroticism, which lingers all about. The constructive precision and its refinement are close to Mies. The experience of the architectural space is universal. The influence of Japanese architecture, more conceptual than formal, is revealed in a respect for nature. It can be seen in the search for refinement through moderation, the elimination of the superfluous object that distract from the experience of place and the preoccupation with light and shade, where a certain parallel with the dark world of the Nordic winter is established. There is an understanding that space, rather than being an immaterial object defined by material surfaces, extends instead as dynamic interactions. The sixth chapter. This proposes a journey to discover some of the unfamiliar residences of most interest which were constructed in the period, and which form part of the system being investigated. Through the study of comparison and one which is geared towards various themes, diverse conclusions are drawn regarding the system being researched. The expertise in substance and form will be a distinctive characteristic in Denmark, demonstrating an approach to the culture of the Orient, both conceptual and formal, and some common interests in certain American architecture. Its teachings sensitize us to a strengthened sense of proportion, scale, materiality, texture and weight and density of space. It values both the tactile and the visual. There is a sensitivity to nature, to the human, to the landscape and to the integrity of the work.

Luz industrial e imagen tecnificada: de Moholy Nagy al C.A.V.S. (Center for Advanced Visual Studies)

El desarrollo de la tecnología de la luz implicará la transformación de la vida social, cultural y económica. Tanto las consideraciones espaciales del Movimiento Moderno, como los efectos producidos por la segunda Guerra Mundial, tendrán efectos visibles en las nuevas configuraciones espaciales y en la relación simbiótica y recíproca que se dará entre ideología y tecnología. La transformación en la comprensión de la articulación espacial, asociada al desarrollo tecnológico, afectará al modo en que este espacio es experimentado y percibido. El espacio expositivo y el espacio escénico se convertirán en laboratorio práctico donde desarrollar y hacer comprensible todo el potencial ilusorio de la luz, la proyección y la imagen, como parámetros modificadores y dinamizadores del espacio arquitectónico. Esta experimentación espacial estará precedida por la investigación y creación conceptual en el mundo plástico, donde los nuevos medios mecánicos serán responsables de la construcción de una nueva mirada moderna mediatizada por los elementos técnicos. La experimentación óptica, a través de la fotografía, el cine, o el movimiento de la luz y su percepción, vinculada a nuevos modos de representación y comunicación, se convertirá en elemento fundamental en la configuración espacial. Este ámbito de experimentación se hará patente en la Escuela de la Bauhaus, de la mano de Gropius, Schlemmer o Moholy Nagy entre otros; tanto en reflexiones teóricas como en el desarrollo de proyectos expositivos, arquitectónicos o teatrales, que evolucionarán en base a la tecnología y la modificación de la relación con el espectador. El espacio expositivo y el espacio escénico se tomarán como oportunidad de investigación espacial y de análisis de los modos de percepción, convirtiéndose en lugares de experimentación básicos para el aprendizaje. El teatro se postula como punto de encuentro entre el arte y la técnica, cobrando especial importancia la intersección con otras disciplinas en la definición espacial. Las múltiples innovaciones técnicas ligadas a los nuevos fundamentos teatrales en la modificación de la relación con la escena, que se producen a principios del siglo XX, tendrán como consecuencia la transformación del espacio en un espacio dinámico, tanto física como perceptivamente, que dará lugar a nuevas concepciones espaciales, muchas de ellas utópicas. La luz, la proyección y la creación de ilusión en base a estímulos visuales y sonoros, aparecen como elementos proyectuales efímeros e inmateriales, que tendrán una gran incidencia en el espacio y su modo de ser experimentado. La implicación de la tecnología en el arte conllevará modificaciones en la visualización, así como en la configuración espacial de los espacios destinados a esta. Destacaremos como propuesta el Teatro Total de Walter Gropius, en cuyo desarrollo se recogen de algún modo las experiencias espaciales y las investigaciones desarrolladas sobre la estructura formal de la percepción realizadas por Moholy Nagy, además de los conceptos acerca del espacio escénico desarrollados en el taller de Teatro de la Bauhaus por Oskar Schlemmer. En el Teatro Total, Gropius incorporará su propia visión de cuestiones que pertenecen a la tradición de la arquitectura teatral y las innovaciones conceptuales que estaban teniendo lugar desde finales del s.XIX, tales como la participación activa del público o la superación entre escena y auditorio, estableciendo en el proyecto una nueva relación perceptual entre sala, espectáculo y espectador; aumentando la sensación de inmersión, a través del uso de la física, la óptica, y la acústica, creando una energía concéntrica capaz de extenderse en todas direcciones. El Teatro Total será uno de los primeros ejemplos en los que desde el punto de partida del proyecto, se conjuga la imagen como elemento comunicativo con la configuración espacial. Las nuevas configuraciones escénicas tendrán como premisa de desarrollo la capacidad de transformación tanto perceptiva, como física. En la segunda mitad del s.XX, la creación de centros de investigación como el CAVS (The Center for Advanced Visual Studies,1967), o el EAT (Experiments in Art and Technology, 1966), favorecerán la colaboración interdisciplinar entre arte y ciencia, implicando a empresas de carácter tecnológico, como Siemens, HP, IBM o Philips, facilitando soporte técnico y económico para el desarrollo de nuevos sistemas. Esta colaboración interdisciplinar dará lugar a una serie de intervenciones espaciales que tendrán su mayor visibilidad en algunas Exposiciones Universales. El resultado será, en la mayoría de los casos, la creación de espacios de carácter inmersivo, donde se establecerá una relación simbiótica entre espacio, imagen, sonido, y espectador. La colocación del espectador en el centro de la escena y la disposición dinámica de imagen y sonido, crearán una particular narrativa espacial no lineal, concebida para la experiencia. Desde las primeras proyecciones de cine a la pantalla múltiple de los Eames, las técnicas espaciales de difusión del sonido en Stockhausen, o los experimentos con el movimiento físico interactivo, la imagen, la luz en movimiento y el sonido, quedan inevitablemente convertidos en material arquitectónico. ABSTRACT. Light technology development would lead to a social, cultural and economic transformation. Both spatial consideration of “Modern Movement” and Second World War effects on technology, would have a visible aftereffect on spatial configuration and on the symbiotic and mutual relationship between ideology & technology. Comprehension adjustment on the articulation of space together with technology development, would impact on how space is perceived and felt. Exhibition space and scenic space would turn into a laboratory where developing and making comprehensive all illusory potential of light, projection and image. These new parameters would modify and revitalize the architectonic space. as modifying and revitalizing parameters of architectonic space. Spatial experimentation would be preceded by conceptual creation and investigation on the sculptural field, where new mechanic media would be responsible for a fresh and modern look influenced by technical elements. Optical experimentation, through photography, cinema or light movement and its perception, would turn into essential components for spatial arrangement linked to new ways of performance and communication. This experimentation sphere would be clear at The Bauhaus School, by the hand of Gropius, Schlemmer or Moholy Nag among others; in theoretical, theatrical or architectural performance’s projects, that would evolve based on technology and also based on the transformation of the relationship with the observer. Exhibition and perfor-mance areas would be taken as opportunities of spatial investigation and for the analysis of the different ways of perception, thus becoming key places for learning. Theater is postulated as a meeting point between art and technique, taking on a new significance at its intersection with other disciplines working with spatial definition too. The multiple innovation techniques linked to the new foundations for the theater regarding stage relation, would have as a consequence the regeneration of the space. Space would turn dynamic, both physically and perceptibly, bringing innovative spatial conceptions, many of them unrealistic. Light, projection and illusory creation based on sound and visual stimulus would appear as intangible and momentary design components, which would have a great impact on the space and on the way it is experienced. Implication of technology in art would bring changes on the observer as well as on the spatial configuration of the art spaces2. It would stand out as a proposal Walter Groupis Total Theater, whose development would include somehow the spatial experiments and studies about formal structure of perception accomplished by Moholy Nagy besides the concepts regarding stage space enhanced at the Bauhaus Theater Studio by Oskar Schlemmer. Within Total Theater, Groupis would incorporate his own view about traditional theatric architecture and conceptual innovations that were taking place since the end of the nineteenth century, such as active audience participation or the diffusing limits between scene and audience, establishing a new perception relationship between auditorium, performance and audience, improving the feeling of immersion through the use of physics, optics and acoustics, creating a concentric energy capable of spreading in all directions. Total Theater would be one of the first example in which, from the beginning of the Project, image is combined as a communicating element with the spatial configuration. As a premise of development, new stage arrangement would have the capacity of transformation, both perceptive and physically. During the second half or the twentieth century, the creation of investigation centers such as CAVS (Center for Advanced Visual Studies, 1967) or EAT (Experiments in Art and Technology, 1966), would help to the interdisciplinary collaboration between art and science, involving technology companies like Siemens, HP, IBM or Philips, providing technical and economic support to the development of new systems. This interdisciplinary collaboration would give room to a series of spatial interventions which would have visibility in some Universal Exhibitions. The result would be, in most cases, the creation of immersive character spaces, where a symbiotic relationship would be stablished between space, image, sound and audience. The new location of the audience in the middle of the display, together with the dynamic arrangement of sound and image would create a particular, no lineal narrative conceived to be experienced. Since the first cinema projections, the multiple screen of Eames, the spatial techniques for sound dissemination at Stockhausen or the interactive physical movement experimentation, image, motion light and sound would turn inevitably into architectural material.

Human-computer interaction based on visual hand-gesture recognition using volumetric spatiograms of local binary patterns

A more natural, intuitive, user-friendly, and less intrusive Human–Computer interface for controlling an application by executing hand gestures is presented. For this purpose, a robust vision-based hand-gesture recognition system has been developed, and a new database has been created to test it. The system is divided into three stages: detection, tracking, and recognition. The detection stage searches in every frame of a video sequence potential hand poses using a binary Support Vector Machine classifier and Local Binary Patterns as feature vectors. These detections are employed as input of a tracker to generate a spatio-temporal trajectory of hand poses. Finally, the recognition stage segments a spatio-temporal volume of data using the obtained trajectories, and compute a video descriptor called Volumetric Spatiograms of Local Binary Patterns (VS-LBP), which is delivered to a bank of SVM classifiers to perform the gesture recognition. The VS-LBP is a novel video descriptor that constitutes one of the most important contributions of the paper, which is able to provide much richer spatio-temporal information than other existing approaches in the state of the art with a manageable computational cost. Excellent results have been obtained outperforming other approaches of the state of the art.

Multiple feature points representation in target localization of wireless visual sensor networks

This paper discusses the target localization problem in wireless visual sensor networks. Additive noises and measurement errors will affect the accuracy of target localization when the visual nodes are equipped with low-resolution cameras. In the goal of improving the accuracy of target localization without prior knowledge of the target, each node extracts multiple feature points from images to represent the target at the sensor node level. A statistical method is presented to match the most correlated feature point pair for merging the position information of different sensor nodes at the base station. Besides, in the case that more than one target exists in the field of interest, a scheme for locating multiple targets is provided. Simulation results show that, our proposed method has desirable performance in improving the accuracy of locating single target or multiple targets. Results also show that the proposed method has a better trade-off between camera node usage and localization accuracy.

Development of a sensorimotor algorithm able to deal with unforeseen pushes and its implementation based on VHDL

Development of a Sensorimotor Algorithm Able to Deal with Unforeseen Pushes and Its Implementation Based on VHDL is the title of my thesis which concludes my Bachelor Degree in the Escuela Técnica Superior de Ingeniería y Sistemas de Telecomunicación of the Universidad Politécnica de Madrid. It encloses the overall work I did in the Neurorobotics Research Laboratory from the Beuth Hochschule für Technik Berlin during my ERASMUS year in 2015. This thesis is focused on the field of robotics, specifically an electronic circuit called Cognitive Sensorimotor Loop (CSL) and its control algorithm based on VHDL hardware description language. The reason that makes the CSL special resides in its ability to operate a motor both as a sensor and an actuator. This way, it is possible to achieve a balanced position in any of the robot joints (e.g. the robot manages to stand) without needing any conventional sensor. In other words, the back electromotive force (EMF) induced by the motor coils is measured and the control algorithm responds depending on its magnitude. The CSL circuit contains mainly an analog-to-digital converter (ADC) and a driver. The ADC consists on a delta-sigma modulation which generates a series of bits with a certain percentage of 1's and 0's, proportional to the back EMF. The control algorithm, running in a FPGA, processes the bit frame and outputs a signal for the driver. This driver, which has an H bridge topology, gives the motor the ability to rotate in both directions while it's supplied with the power needed. The objective of this thesis is to document the experiments and overall work done on push ignoring contractive sensorimotor algorithms, meaning sensorimotor algorithms that ignore large magnitude forces (compared to gravity) applied in a short time interval on a pendulum system. This main objective is divided in two sub-objectives: (1) developing a system based on parameterized thresholds and (2) developing a system based on a push bypassing filter. System (1) contains a module that outputs a signal which blocks the main Sensorimotor algorithm when a push is detected. This module has several different parameters as inputs e.g. the back EMF increment to consider a force as a push or the time interval between samples. System (2) consists on a low-pass Infinite Impulse Response digital filter. It cuts any frequency considered faster than a certain push oscillation. This filter required an intensive study on how to implement some functions and data types (fixed or floating point data) not supported by standard VHDL packages. Once this was achieved, the next challenge was to simplify the solution as much as possible, without using non-official user made packages. Both systems behaved with a series of interesting advantages and disadvantages for the elaboration of the document. Stability, reaction time, simplicity or computational load are one of the many factors to be studied in the designed systems. RESUMEN. Development of a Sensorimotor Algorithm Able to Deal with Unforeseen Pushes and Its Implementation Based on VHDL es un Proyecto de Fin de Grado (PFG) que concluye mis estudios en la Escuela Técnica Superior de Ingeniería y Sistemas de Telecomunicación de la Universidad Politécnica de Madrid. En él se documenta el trabajo de investigación que realicé en el Neurorobotics Research Laboratory de la Beuth Hochschule für Technik Berlin durante el año 2015 mediante el programa de intercambio ERASMUS. Este PFG se centra en el campo de la robótica y en concreto en un circuito electrónico llamado Cognitive Sensorimotor Loop (CSL) y su algoritmo de control basado en lenguaje de modelado hardware VHDL. La particularidad del CSL reside en que se consigue que un motor haga las veces tanto de sensor como de actuador. De esta manera es posible que las articulaciones de un robot alcancen una posición de equilibrio (p.ej. el robot se coloca erguido) sin la necesidad de sensores en el sentido estricto de la palabra. Es decir, se mide la propia fuerza electromotriz (FEM) inducida sobre el motor y el algoritmo responde de acuerdo a su magnitud. El circuito CSL se compone de un convertidor analógico-digital (ADC) y un driver. El ADC consiste en un modulador sigma-delta, que genera una serie de bits con un porcentaje de 1's y 0's determinado, en proporción a la magnitud de la FEM inducida. El algoritmo de control, que se ejecuta en una FPGA, procesa esta cadena de bits y genera una señal para el driver. El driver, que posee una topología en puente H, provee al motor de la potencia necesaria y le otorga la capacidad de rotar en cualquiera de las dos direcciones. El objetivo de este PFG es documentar los experimentos y en general el trabajo realizado en algoritmos Sensorimotor que puedan ignorar fuerzas de gran magnitud (en comparación con la gravedad) y aplicadas en una corta ventana de tiempo. En otras palabras, ignorar empujones conservando el comportamiento original frente a la gravedad. Para ello se han desarrollado dos sistemas: uno basado en umbrales parametrizados (1) y otro basado en un filtro de corte ajustable (2). El sistema (1) contiene un módulo que, en el caso de detectar un empujón, genera una señal que bloquea el algoritmo Sensorimotor. Este módulo recibe diferentes parámetros como el incremento necesario de la FEM para que se considere un empujón o la ventana de tiempo para que se considere la existencia de un empujón. El sistema (2) consiste en un filtro digital paso-bajo de respuesta infinita que corta cualquier variación que considere un empujón. Para crear este filtro se requirió un estudio sobre como implementar ciertas funciones y tipos de datos (coma fija o flotante) no soportados por las librerías básicas de VHDL. Tras esto, el objetivo fue simplificar al máximo la solución del problema, sin utilizar paquetes de librerías añadidos. En ambos sistemas aparecen una serie de ventajas e inconvenientes de interés para el documento. La estabilidad, el tiempo de reacción, la simplicidad o la carga computacional son algunas de las muchos factores a estudiar en los sistemas diseñados. Para concluir, también han sido documentadas algunas incorporaciones a los sistemas: una interfaz visual en VGA, un módulo que compensa el offset del ADC o la implementación de una batería de faders MIDI entre otras.