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Este trabajo abarca varias técnicas de desarrollo de HDA y creación de simulaciones de fluido de manera procedural y en el que se crea una herramienta de visualización de fluidos para la protección costera.

El enfoque del proyecto es diseñar un software de realidad virtual para hacer el siguiente experimento: Se simula un entorno de oficina y se colocan personajes virtuales con apariencia típicas que se encuentran en una oficina, como oficinistas, y se les asignan actividades habituales, como hacer reuniones. El objetivo es observar en caso del incendio, si el participante del experimento seguiría a estos avatares y si se prestan atención en las señales de evacuación. El experimento divide a los participantes en cuatro grupos. Las diferencias se marcan en: · Con o sin presencia de otros avatares. · Con o sin formación previa sobre el tema de la gestión de riesgos. Al inicio de la simulación, solo se les permite girar la cabeza y observar el entorno. Después de un período de adaptación inicial, se activa una alarma de incendio. A partir de ese momento, se les da la libertad de moverse y explorar la oficina virtual y se registra el comportamiento de los participantes (trayectorias y rastreo ocular). Una vez que los participantes llegan a un punto de salida, se concluye la simulación y se pasa a la fase final del experimento. Aquí, se les pide a los participantes que completen un cuestionario que incluye preguntas sobre su experiencia durante la simulación y su percepción del entorno virtual. Con los datos recopilados durante la simulación y las encuestas, se puede realizar análisis posteriores para llevar a cabo estudios de gestión de riesgos y simulación de multitudes.

Este Trabajo Final de Máster se enfoca en explorar la interacción bidireccional entre entornos de realidad virtual y elementos del mundo real utilizando como base el concepto de los gemelos digitales. Los gemelos digitales son réplicas virtuales de objetos, sistemas o procesos del mundo real que permiten a los usuarios interactuar en un espacio compartido, superando las barreras de ubicación física. Estos se utilizan para realizar simulaciones o análisis de procesos en entornos virtuales, representando objetos físicos en el mundo real. En este proyecto se busca llevar esta interacción un paso más allá. Se pretende que la manipulación realizada en el entorno virtual tenga un impacto directo en elementos reales adaptados para este propósito, y que, a su vez, las acciones realizadas en el mundo real modifiquen el entorno virtual. De esta manera, se logra una correspondencia efectiva entre los dos mundos, mejorando la coexistencia y la integración entre ambos

Este proyecto de innovación se centra en explorar y construir una solución ante un problema de dilapidación gastronómica presente día a día en las escuelas de ciencias culinarias y gastronómicas durante el proceso del emplatado. Este problema surge ante el desconocimiento de la conducta de los integrantes empleados debido a la prematura experiencia del alumnado. Este hecho dificulta prever el comportamiento de ciertos ingredientes en una superficie concreta y, por ello, tener que repetir en más de una ocasión el proceso. Acotando la investigación al ámbito de los postres, mediante la simulación de cremas, coberturas y otras salsas dulces relacionadas con la repostería, selograría una visualización físicamente correcta del comportamiento de dichos productos en base a sus propiedades durante la etapa teórica de la formación. Además, dichas simulaciones podrían ser visualizadas repetidamente, congeladas en momentos clave para su comprensión, o adaptadas a nuevos requerimientos por su naturaleza procedural. Este método serviría de refuerzo durante la preparación teórica del alumno, antes de enfrentarse al retopráctico, por lo que resultaría en un ulterior ahorro en tiempo y materias primas. De esta manera obtendremos un beneficio para el alumno, otorgándole una nueva herramienta actualizada con la que poder comprender mejor el comportamiento físico de los fluidos, visualizar con exactitud las propiedades que debe tener una crema bien elaborada y practicar haciendo uso del creciente mundo de la simulación digital. Además, se conseguiría propiciar la sostenibilidad de las escuelas a través del ahorro de comestibles y, por lo tanto, también económico. Mediante el workflow habitual de producción (pre-producción, producción y postproducción), y el programa HoudinideSideFX, se ha construido un instrumento cuya función es visualizar el comportamiento de dichas simulaciones de fluidos. Además, proporciona al usuario, mediante un botón controlador, la oportunidad de modificar la

The goal of this end of degree project is to develop an ecosystem simulator that can be used to learn about how ecosystems work in an easy, visual and fun way. Studying any discipline is tough, therefore this project aims to make this learning journey more easy-going and fun. The ecosystem used in this project includes an environment with different biomes, trees, animals and food, all of which influence each other. Most similar projects use either dozens/hundreds of concurrent entities or thousands of simple entities. This project also aims to bring simulators to the next level by running them with thousands of not-simple entities at the same time with an agent-based system while keeping a decent framerate. This project tries to make a balance between a great amount of entities and an interesting entity behaviour. Due to the fact that such a simulator can take years and multiple people to develop, this specific project is a prototype that aims to show the great potential that this project has. This simulator is done with Unity Technologies, Blender and C#. On one hand, Blender has been used to build a 1x1 kilometers 3D island that is being used in the simulation. Unity and C# are used to put everything together and program all the systems and AIs. For this project, the used methodology is agile and feature-driven development, where short iterations are made. On each iteration, a new feature is added and in the case that a bug was found during the previous iteration, it is fixed during the current one.

The International Thermonuclear Experimental Reactor (ITER) is a nuclear fusion project that has the need, among other things, to compute and measure in real time the state of the magnetic field in charge of confining the plasma in combustion. In this project, a firmware implemented with FPGA is developed to compute and process magnetic field data. On one hand, a firmware is elaborated. It has to receive data coming from integrators, analyse, process and finally send them through one of the ITER communication network called SDN. On the other hand, it is about a critical system, and therefore, it has followed a validation process through simulations and hardware tests., El International Thermonuclear Experimental Reactor (ITER) es un proyecto de fusión nuclear que tiene la necesidad de computar en tiempo real el estado del plasma en combustión. En este proyecto se desarrolla un firmware implementado en FPGA específico para computar y procesar estos datos. Por una parte, se elabora el firmware. Este tiene que recibir los datos que provienen de unos integradores, analizarlos, procesarlos y finalmente enviarlos a través de una de las redes de comunicación de ITER llamada SDN. Por otro lado, se trata de un sistema crítico, por lo que ha seguido un proceso de validación mediante simulaciones y pruebas de hardware.?, L'International Thermonuclear Experimental Reactor (ITER) és un projecte de fusió nuclear que té la necessitat de mesurar i computar en temps real l'estat del camp magnètic encarregat de confinar el plasma en combustió. En aquest projecte, es desenvolupa un firmware implementat en FPGA específic per computar i processar les dades del camp magnètic. Per una part, s’elabora el firmware. Aquest ha de rebre dades provinents d'uns integradors, analitzar-les, processar-les i finalment enviar-les a través d'una de les xarxes de comunicació d' ITER anomenada SDN. D’altra banda, es tracta d'un sistema crític i, per tant, s'ha hagut de validar mitjançant un procés de simulacions i tests per hardware.

En líneas generales, el objetivo principal de este Trabajo Final de Grado es analizar y simular un accidente sucedido en un estadio de fútbol, para posteriormente proponer y analizar la efectividad de las medidas tomadas. Para ello, se iniciará el proyecto con una fase de investigación, donde paralelamente se ahondará en las simulaciones de multitudes en Houdini, pero también en el funcionamiento de los planes de autoprotección y la seguridad en este tipo de recintos. Además, se detallarán aquellos factores que caracterizan a las multitudes, con el objetivo de generar unas simulaciones realistas, ricas técnicamente y que se puedan implementar posteriormente en un entorno real. Posteriormente se procederá a la generación de dichas simulaciones. Durante esta fase, se investigará sobre el accidente, se modelarán todos aquellos recursos necesarios, como puede ser la geometría del estadio y se generarán las simulaciones. En esta memoria se puede encontrar detalle del funcionamiento conceptual y técnico de cada una de las simulaciones, así como sus similitudes y diferencias. Finalmente, en la última fase del proyecto se analizarán las simulaciones obtenidas y se propondrán medidas para evitar el accidente acordes con lo analizado.

El proyecto trata sobre la creación de un entorno virtual en el que se van a producir animaciones y simulaciones 3D, haciendo uso del software de Houdini, y de la creación de una canción en Cakewalk que controle el funcionamiento de los efectos. Una parte importante del proyecto se basa en mostrar la eficacia de producir dichas animaciones y simulaciones disponiendo del archivo original de la música, ya que con este archivo se podrían exportar diferentes pistas, instrumentos o sonidos de la propia canción producida. Poder optar a obtener archivos separados por grupos de instrumentos o sonidos es una gran ventaja, porque posibilita gestionar el procesamiento del audio dentro de Houdini y su resultado estético final. Esto se debe a que en una canción, no todos los sonidos e instrumentos tienen la misma intensidad. Clasificarlos por grupos en función de su rango dinámico y aplicarlos en diferentes animaciones mediante un proceso de gestión del audio facilita que el resultado pueda ajustarse de manera mucho más precisa. Además, esta práctica mejora el resultado final, ya que se facilita la distinción de los diferentes instrumentos y sonidos de manera visual. Finalmente, en este proyecto se propone crear un vídeo final de alta calidad como resultado de la ejecución de los efectos y la música en el que se va a enseñar el aspecto que podría tener un entorno virtual con elementos que reaccionan al audio

La Teràpia Visual és una modalitat d’optometria que any rere any està guanyant acceptació en la comunitat científica a través dels resultats publicats en articles científics. La tendencia actual en el desenvolupament de tractaments de Teràpia Visual ha sigut la digitalització de les teràpies i la realització de múltiples avaluacions que també permetin la integració de les habilitats entrenades en la vida diària dels pacients. L’objectiu d’aquest estudi és trobar oportunitats en el camp de la Teràpia Visual per tal d’aplicar les noves tecnologies en el tractament de diferents deficiències visuals de la població. Per fer-ho, s’ha exposat el recorregut i direcció actual del sector. S’han descrit les diferents modalitats de Teràpia Visual oficials segons SIODEC i la prevalença de les principals anomalies oculomotores. S'ha mencionat potencials fonts de pacients existents en l'actualitat i per últim s’ha explicat l’ús existent de les tecnologies utilitzades dels els metaversos aplicats en altres sectors i com podria aplicar-se en Teràpia Visual., La Terapia Visual es una modalidad de optometría que año tras año está ganando aceptación en la comunidad científica a través de los resultados publicados en artículos científicos. La tendencia actual en el desarrollo de tratamientos de Terapia Visual ha sido la digitalización de las terapias y la realización de múltiples evaluaciones y ejercicios simultáneos a través de pruebas gamificadas que permitan, a su vez, la integración de las habilidades entrenadas a la vida diaria de los pacientes. El objetivo de este estudio es encontrar oportunidades en el campo de la Terapia Visual para aplicar nuevas tecnologías en el tratamiento de diferentes deficiencias visuales de la población. Para ello, se ha expuesto el recorrido y dirección actual del sector. Se han descrito las diferentes modalidades de Terapia Visual oficiales según SIODEC y la prevalencia de las principales anomalías oculomotoras. Se han mencionado potenciales fuentes de pacientes existentes en la actualidad y por último se ha explicado el uso existente de las tecnologías utilizadas de los metaversos aplicados en otros sectores y cómo podría ser aplicado en Terapia Visual., Visual Therapy is an optometry modality that year after year is obtaining acceptance over the scientific community through its published results in scientific articles. The actual tendency in treatment development has been at the digitalisation of the therapies and the simultaneous realization of multiple evaluations and while also training the targeted abilities through gamified tests which also allow its integration to the patients day to day necessities. The objective of this study is to find opportunities in the field of Visual Therapy to apply new technologies in the treatment of diverse visual deficiencies of the population. In order to do that, we described the different modalities of Visual Therapy following SIODEC standards and the prevalence of the diverse oculomotor anomalies. We list different sources that may help therapists reach more patients and remark on the direction Visual Therapy is headed on the development of new therapies and services. Lastly, we elaborate on the use of Metaverse related technologies, its uses in other sectors and the potential application in Visual Therapy.

Aquest treball consisteix en l'estudi i desenvolupament d'una aplicació web per visualitzar l'evolució temporal de planetes com la Terra mitjançant gràfics per ordinador. En cada capítol del document es presenta un nou concepte o característica que en conjunt, conformen un model simplificat amb l'objectiu de recrear el desenvolupament que va experimentar planeta, des de la seva formació fins a l'actualitat, explorant els diferents mecanismes que l'han portat a ser com el coneixem avui dia. Alguns d'aquests són el naixement del protoplaneta en el període de formació inicial, l'origen de l'aigua, oceans i rius i els efectes erosius que causen en el terreny, la formació i moviment de les plaques tectòniques, els efectes de la llum en travessar una atmosfera i dispersar-se i el funcionament del clima a escala global entre altres coses. Com s'explica al document, simular tots aquests fenòmens és una tasca molt complexa i s'han realitzat moltes simplificacions per tal de fer viable aquest projecte. L'objectiu final no és tractar de simular el planeta Terra, ja que és una tasca de gran complexitat i amb infinitat de variables, en comptes d'això, es vol explorar la idea d'implementar de forma simplificada el que coneixem del nostre planeta, i també d'altres, per a obtenir resultats aproximats que puguem extrapolar per a poder veure quin aspecte podrien tindre altres planetes habitables com el nostre, o crear uns altres totalment únics amb característiques molt diverses., Este trabajo consiste en el estudio y desarrollo de una aplicación web para visualizar la evolución temporal de planetas como la Tierra mediante gráficos por ordenador. En cada capítulo del documento se presenta un nuevo concepto o característica que en su conjunto, conforman un modelo simplificado con el objetivo de recrear el desarrollo que experimentó planeta, desde su formación hasta la actualidad, explorando los diferentes mecanismos que han llevado a ser como lo conocemos hoy en día. Algunos de estos son el nacimiento del protoplaneta en el período de formación inicial, el origen del agua, océanos y ríos y los efectos erosivos que causan en el terreno, la formación y movimiento de las placas tectónicas, los efectos de la luz al atravesar una atmósfera y dispersarse y el funcionamiento del clima a nivel global entre otras cosas. Como se explica en el documento, simular todos estos fenómenos es una tarea muy compleja y se han realizado muchas simplificaciones para hacer viable este proyecto. El objetivo final no es tratar de simular el planeta Tierra, puesto que es una tarea de gran complejidad y con infinidad de variables, en su lugar, se quiere explorar la idea de implementar de forma simplificada lo que conocemos de nuestro planeta , y también otros, para obtener resultados aproximados que podamos extrapolar para poder ver qué aspecto podrían tener otros planetas habitables como el nuestro, o crear otros totalmente únicos con características muy diversas., This work consists of the study and development of a web application to visualize the temporal evolution of planets such as Earth using computer graphics. Each chapter of the document introduces a new concept or functionality which together form a simplified model in order to recreate the development experienced by the planet, from its formation to the present day, by exploring the various mechanisms that led it to be as we know it today. Some of these are the birth of the protoplanet in the initial formation period, the origin of water, oceans and rivers and the erosive effects they produce on the soil, the formation and movement of tectonic plates, the effects of the light as it traverses an atmosphere and disperses and how climate works on a global scale, among other things. As described in the document, simulating all these phenomena is a very complex task and many simplifications have been made in order to make this project viable. The ultimate goal is not to try to simulate the planet Earth, as it is a great complex task and with countless variables, instead, we want to explore the idea of implementing in a simplified way what we know about our planet, and others, to obtain approximate results that can be extrapolated to see what other habitable planets like ours might look like, or create totally unique others with very different characteristics.

The use of simulation tools has been widely used to learn something. Simulation tools have the advantage of imitating a process similar to the actual situation. But there are only a few researches that examine the students' engagement in using simulation tools in the learning process so that it affects the student learning outcomes. This research aims to analyze the factors of GUI simulation as learning media for learning signal coding technique based. PLS-SEM method was used to investigate the impact and the relationship of factors of GUI simulation such as easiness of use, media attractiveness and learning content toward learning outcome. The results showed that the learning content factor gave a large and significant contribution toward learning outcomes, while easiness of use and media attractiveness made a small contribution to the learning outcome, Peer Reviewed

In recent years, a growing number of users require a fast wireless communication to access networks. This demand has had an impact on the increasing amount of radio-over-fiber solutions, as these provide a rapid, reliable connection and allow many users to connect to the same fiber link. The aim of this thesis is to give to the engineers the computation and simulations tools, using different Mach-Zehnder Modulators configurations, that may provide them with the help needed in the process of deploying a radio-over-fiber system. Additionally, it can help them to use the least minimum power required, offering the same quality.

When a photovoltaic facility has a dispersion of characteristics, a difference in the working temperatures or a full or partial shading or dirt in the PV panels, we say that the installation is working under mismatched conditions. This cases can entail an important impact on the energy production and the safety of the facility. In this study the documentation, maintenance and restructuring of a code project able to provide simulations of photovoltaic generators working under mismatched situations is explained. This project uses optimization techniques, applied using object oriented programming (OOP). Starting from the most basic devices that conform a photovoltaic generator, its components are represented by classes. These components are combined in series or parallel following the respective electric laws (Kirchhoff’s laws). As the complexity of these structures grow, so does their mathematical representation. Therefore, advanced calculus methods are used to solve the involved systems of non-linear equations. The main output of this model is the current - voltage characteristic of the photovoltaic generator. In order to establish a solid base for future improvements and more ambitious projects, the code will be properly commented, documented and restructured. In order to make it easier for engineers to use it in other code projects, it will be converted into a software library. It will consist of software pages and its proper documentation, including a theoretical explanation, a technical description and a user’s guide. All the components will be free software in order to grant permission to use, copy, modify, and distribute them and their documentation (under the terms of the GNU General Public License).

Due to its high design freedom and flexibility, Additive Manufacturing is often used as an alternative to the conventional manufacturing. In order to be competitive, as many advantages of additive manufacturing as possible should be used. Lightweight construction is one of the biggest advantages of Additive Manufacturing. However, implementing lightweight design for AM requires different product design approaches compared to conventional development. To achieve the lowest possible part volume combined with a high strength, it is possible to optimize the topology. At first, stresses in the part are localized by means of a numerical simulation. Subsequently, by comparing them with a reference, high and low-loaded regions can be separated. Thus, a targeted volume reduction can be implemented. In order to be able to respond to the restrictions of the manufacturing processes, these must be considered before the optimization. This paper presents a procedure for a production-oriented simulation and topology optimization for the SLM process (Selective Laser Melting). An approach to optimizing the topology is presented with regard to technical as well as economic aspects. In doing so, methods for the quantitative assessment of success factors are used. Since various procedural restrictions exist for the SLM process, such as anisotropy or thermal distortion, these must be considered before the topology optimization. This is done by adjusting the simulation and optimization parameters. Through this adaptation, it is also possible to take into account the previous assembly concept and to improve it by an integrated design. In order to comply with required tolerances, both a thermal and mechanical postprocessing is necessary. This in turn must already be considered in the optimization task. This approach is illustrated by the optimization of the topology of the pelvis of "Sweaty", the humanoid robot. This robot was developed by students and is able to play football. It is a part

The recent appearance of hybrid CNC machines – which can both add and remove material to an object – has facilitated a new type of approach to the problem of repairing damaged com- ponents. Up to now, repair operations have been carried out manually and for this reason they are errors prone, costly and time consuming. The use of precise and repeatable CNC machines in this field is therefore very attractive for the sake of reliability and repeatability. One of the biggest obstacles on the automation of the repairing process is that the CAM software requires a solid CAD model to create the toolpaths needed to perform additive operations. The present work proposes the use of octrees to detect the damaged spot starting from the 3D scan of the damaged object. A software named DUOADD has been developed to convert these informa- tions into a CAD model suitable to be used by the CAM software. The new workflow designed to perform a complete repair operation is here described. DUOADD allows to approach the repairing problem from a new point of view opening the doors to save both time and money. The successful application of the entire process to repair a damaged die injection mold is also here reported. §DUOADD=DUOADD Uses Octree sAs Damage Detector

In this research, an optimization design of the lattice structure is investigated, which is based on the ground structure method. In recent years, as a result of rapid development of additional manufacturing technology, it has become possible to manufacture complicated shapes including periodic lattice structure. However,in real metal lattice samples, geometric imperfections may exist in every unit because of the stochastic influence of feasible processing path. In this study, a new ground structure method which does not leave elements with small cross sectional area was proposed. In particular, the effect of geometric constraints caused by additive manufacturing techniques on optimized results are discussed based on the robust topology optimization combining perturbation methods for quantifying uncertainty. In the end, a robust topology optimization was also discussed as a problem to minimize expected value and standard deviation of compliance.

The main objective of this research is to investigate the newly designed geometry and process parameters in a dual matrix composite filament co-extrusion technology (CFC), a co-extrusion of continuous carbon fiber pre-impregnated with thermoset (1.5K) also known as composite carbon fiber (CCF) filament with a special binder thermoplastic filament. Accordingly, non-isothermal fluid flow and particle tracking analysis were employed in order to examine the melt flow dynamics. In addition, critical parameters like pressure drop, velocity, shear stress, residence time, and swelling/shrinkage ratio were evaluated. In particular, the computational fluid dynamics (CFD) simulations indicates distress in the conventional die design, recirculation and stagnation of melt flow in the dead zones causing longer melt residence leading to the thermal degradation of thermoplastic material. Furthermore, a new print head was designed to expedite the solution for the possible flow instabilities that may lead to a disparity in the material and mechanical properties, a side- fed mandrel die was used as a melt distributor. Consequently, the side- fed mandrel die ensured a homogeneous melt distribution inside the CFC print head, particularly at the die exit.

New methodologies of Design for Additive Manufacturing (DFAM) and relative CAx tools are the key enabling technologies allowing to get the major benefits from AM. It is evident that an increased integration of all CAx phases would lead to a more efficient design and engineering workflow. One of the major bottlenecks of such a holistic approach, which affects AM product time-to-market and restricts its commercial exploitation, is the need of a high amount of time and human resources for simulation, modelling and postprocessing of all the engineering activities. That is not always manageable, especially during a preliminary stage of concept design or feasibility analysis. Modern mathematical approaches are facing, with the ambition to contribute to some of the most challenging engineering tasks to fulfil strict requirements of structural resistance, lightness, noise, static and dynamic stiffness. The effectiveness of analytical and geometrical tools and methods for the study and the optimization of shapes were already demonstrated. As an example, it is well known that small fillet radius are stress concentrators and must be avoided for a robust design of structural parts. In the same way, we can demonstrate that poorly uniform temperature distribution of the material during additive layer manufacturing can be correlated with geometrical section areas and variations along the growing axis, as well as with supports shape configurations. In this paper, a novel approach is presented which identifies optimal orientation and support configurations, uniquely based on geometrical criteria. The benefits are avoiding long structures to minimise the amount of waste material, accounting for the distribution of the piece weight, effectively draining the thermal field from all the areas of the piece to the build platform. With FE based macroscale process simulations, it is possible to evidence improved thermal strain distributions of the optimised configuration. As part of the R&D

This contribution focuses on the experimental investigation and material modelling of the crosslinking of UV curing polymers used in additive manufacturing processes such as dig- ital light processing and stereolithography. First photocalorimetric measurements with varying temperature and light intensity are shown. From the exothermic specific heat flows measured during the crosslinking reaction, the degree of cure can be determined for each experimental scenario. It is shown that the test temperature and light intensity have a significant influence on the crosslinking reaction. A first modelling approach for the mathematical description of the crosslinking reaction is pre- sented. Moreover, parameter identification of the proposed model is conducted using the com- mercial optimisation program LS-OPTQR

This paper presents a Compliant Rotational Reducer Mechanism (CRRM), under development in the context of a space project. The CRRM is optimized using structural and flexural topology optimization for respectively, the structural and flexure problems. With respect to the structural optimization, a mass reduction of 20 % and a shift of the lowest undesirable eigenfrequency from 400 to 1000 Hz was obtained. For the flexural optimization, a Rotational Center Constraint (RCC) and a Floating Structure Modal Objective Function (FSMOF) are introduced. The FSMOF allows to impose a desired eigenmode of a mechanism. The RCC and FSMOF are applied to generate a flexure pivot with eigenmodes of a typical flexure pivot. Finally, these results are integrated into a novel version of the CRRM.

Additive Manufacturing allows to design and realize 3D parts, integrating additional functionalities offered by the interaction between complex shapes and the material properties. Results can be even more appealing when functional materials, like Shape Memory Alloys, are printed: new opportunities for smart devices can be opened. In the present bulk and lattice structures of Nitinol were additively manufactured with a Seletive Laser Melting. A pulsed laser, which is more suitable for manufacturing thin parts, was selected to process the initial powder. The selection of the process parameters, like laser power and exposure time, was performed for maximizing the relative density. Furthermore, the microstructure and the martensitic transformation temperatures were analyzed through X-rays diffraction and differential scanning calorimetry, respectively. A comparison between the initial powder and SLMed parts was also considered. Finally, the mechanical properties of Niti builts under compression were tested for both bulk and lattice structures.

Any manufacturing process which allows to create a product in its finished form without the need for other machining operations belongs to Net Shape Forming family. Additive Manufacturing (AM) is a part of NSF family; it allows to build 3D objects by adding layer-upon-layer of material (polymers, metals, ceramics) and includes different manufacturing techniques as stated by ISO/ASTM Standard. In order to get good results by the application of these manufacturing techniques, some technological problems has to be faced and solved. They mainly concern: temperature control of the material to be processed, characteristics of the energy source for material transition, control of the power transferred to the material, scanning system’s head control, 3D model’s layer definition, generation of the laser point’s trajectories. All of these aspects have the same importance to guarantee the quality of the product and they are sinergically linked each other. As an example, the power of the energy source and the temperature of the material are strongly related; the power transferred to the material is related to the trajectories running speed; the 3D model’s layer definition influences the resolution of the positioning system; on the performances and control of the scanning head, depends the accuracy of the trajectories. The quality of the product strongly depends on all these aspects as well as on the technical solution to realize them. In other words, the machine implementing the AM technological process is crucial for the product’s manufacturing. From the early stages of machine’s concept, a multidisciplinary and synergic approach which allows to take into account all the different aspects involved in the process must be followed. This is the typical approach followed by Mechatronics; as a matter of fact, Mechatronics concerns the the synergistic application of mechanics, electronics, controls and computer engineering in the development of product and systems through an integra

Recently, a simplified macroscopic and semi-analytical thermal analysis of Laser Meta lDeposition (LMD) has been submitted to publication. The model is fast enough to simulate the entire process. The proposed approach enables to compute: temperature, solidification and solid-state phase transitions kinetics. Process parameters, substrate characteristics and heat sources due to the enthalpy change during phase transitions are taken in to account as well as convection due to the carrying and shielding gas. The present work exploits the proposed model to investigate the influence of some process parameters in order to determine whether complex multiphase steels (such as high strength steels) could be controllably obtainedby LMD. Indeed, material properties of such steels are not only a matter of chemical composition but also and mostly a matter of phase proportions in a multiphase mixture (austenite, ferrite, pearlite, bainite and martensite). Within this framework, temperature control strategies during the process are numerically tested for a simple cylindrical geometry.

Laser Beam Melting (LBM) is currently garnering industrial attention and many numerical researches have been carried out in order to understand the physics behind the process. However, due to the gap between the grain scale (micrometres) and the bead scale (millimetres), current state-of-the-art multi-physical models are computationally expensive as each powder grain is individually represented. Hence, simulating more than a single LBM track in a reasonable computational time is a challenging task. To overcome this limitation, a new mesoscopic approach is proposed, which intends to bridge the fine thermo-hydrodynamic representation and the macroscopic thermal models. The powder bed is represented by a homogeneous medium with both equivalent thermal and fluid properties. A bulk heat source is considered when the laser heats the powder bed whereas a surface heat flux is imposed on the melted powder bed surface. Apparent viscosity and surface tension are attributed to the homogenized medium so that modelling powder densification, melting and spheroidization of the melt pool is made possible by solving compressible Navier-Stokes equations. In addition, thermocapillary effects as well as vaporisation-induced recoil pressure are implemented, so that realistic thermo-hydrodynamic phenomena are successfully taken into account.

With the help of current approaches in the mechanics of additively manufactured deformable solids, a non-classical mathematical model is developed to predict the stress-strain state of polymer layers gradually formed on a rotating substrate in an arbitrary number of continuous stages of centrifugal material application. On the basis of numerous calculations performed, the qualitative and quantitative features of the residual technological stresses distributions in the finished cylindrical product for different variants of its release from the mechanical loading and the kinematic bonds acting during the manufacturing process are analyzed in detail. Previously unknown mechanical effects are found. The appropriate recommendations of a practical nature are given.

This study analyses canine limb-sparing implants with an integrated lattice structure, manufactured in Ti-6Al-4V ELI alloy using Electron Beam Melting (EBM) technology. The research aim is to determine the technical risk associated with the implant through probabilistic numerical analysis. A series of boundary conditions are employed on the implants in order to investigate the robustness of the design. The output stress and strain values are then employed to further examine fatigue life parameters under cyclic loading of the implants. The probabilistic numerical analysis has successfully identified the location of a key failure mode (yield stress limit) and the modelling correlated to veterinary case-study observations. In regard to the lattice structure, it is shown that the structure does provide mechanical integrity to the implant assembly, but the geometry requires significant simplification while modelling. This is primarily due to: (a) the limitations of CAD tools in generating NURB surfaces from point cloud data, and (b) the node and element count associated with these small structures makes the model computationally expensive.

Heart valve diseases are among the leading causes of cardiac failure around the globe. Current advances in imaging technology, in numerical simulation and in additive manufacturing are opening new frontiers in the field of development of new personalised prosthetic devices. The 3D printing technique could allow the realisation of personalised models for each patient undergoing valve replacement surgery. A CAD model of an aortic valve prosthesis was designed on the basis of elliptic-hyperboloid formulation. The resulting CAD model was used both to perform numerical in-silico simulation and to design a modular mould for AV fabrication. Simulations were performed through a novel hybrid approach based on RBF mesh morphing technique and CFD simulations. The polymeric aortic valve was manufactured by 3D printed process and spray deposition technique. To assess the in-vitro valve properties, the prototype was inserted in a custom mock circulatory loop to reproduce the aortic flow conditions. The manufacturing process of both the mould and the valve was successful and the in-vitro testing showed an effective orifice area (2.5 mm2) and regurgitation fraction (5%) in accordance with the ISO-5840-2. The novel simulation strategies have revealed to be a promising approach to test both structural and functional device performances.

The finite element analysis (FEA) of components’ build-up has recently proved to be a valuable tool for accompanying the product and process development during additive manufacturing (AM). In this numerical method a first key aspect is the heat input modelling of laser scanning for building-up AM products of industrial relevance, as close to reality as possible, by applying equivalent heat source models. Based on these reduction models the stress distribution in a successive thermo-mechanical simulation is calculated approximating the sum of thermal, elastic and plastic stresses during processing and the remaining elastic and plastic stresses after cooling. A further key aspect is, thereupon, to predict the final shape of the additively manufactured component by means of the FEA after its removal from the substrate or the support structures. This work aims to analyze the development of stresses in components during their additive laser processing and cooling to ambient temperature as well as after post-processing cutting operations. Moreover, the associated to stress development simulated final part shape is evaluated with the aid of 3d measurements on an additively manufactured twin cantilever of industrial relevance. Finally, based on the rendered simulation results a compensation of the undesired shape distortions is proposed based on reverse engineering approach.

Directed energy deposition (DED), which is one of additive manufacturing applicable to metals, laminates the material on a baseplate by melting and solidifying with a high-power heat source. In terms of powder-based DED, the material waste tends to be large because powder flow is difficult to converge on the melt pool precisely. This study evaluates the variation in powder distribution when the deposition height is changed in order to obtain the optimal gas-flow rate and powder-nozzle shape. The powder flow is estimated with a computational fluid dynamics simulation based on Euler-Lagrange approach. The simulation results indicate that the proposed nozzles can achieve the high powder convergence stably even if the total amount of gas supply is reduced.

Computational simulations represent a powerful tool for the pre-procedural clinical assessment of minimally invasive cardiovascular interventions [1]. Patient-specific simulations rely on the accurate numerical implementation of both geometrical and mechanical features. While current imaging techniques are able to depict accurately patient-specific anatomies, at date, a similar image-based tool capable to retrieve subject-specific material properties is missing. The scope of this study is to present a framework, involving in silico tools and 3D printing, for the refinement of an image-based technique [2] capable to retrieve in vivo patient-specific mechanical information from functional and morphological magnetic resonance imaging (MRI) data. The workflow consists in three main steps: (i) selection and mechanical testing of 3D commercially available deformable 3D printed materials; (ii) fluid-structure interaction (FSI) simulation of a vessel model under pulsatile regime; (iii) 3D printing of the model and experimental replica in MRI environment. Finally, the imagebased technique is applied to both numerical (ii) and MRI data (iii) to retrieve material information to compare to reference (i). The described workflow strategy was successfully implemented by our group. The deformable material TangBlackPlus FLX980 was selected and mechanically tested, resulting in an elastic module (E) of 0.50 0:02 MPa. A vessel model was designed for FSI simulations (E=0.50 MPa) as well as 3D printed with an Objet500 Connex machine (Stratasys, Minnesota, USA) to acquire MRI data. The image-based technique was used to retrieve the E value from numerical and experimental data. In silico, the indirect material evaluation resulted in E=0.49 MPa, while in vitro we found E=0.51 0:04 MPa. Moreover, other values of E (up to 32 MPa) were tested in silico, leading to matching results as well. Other deformable materials will be investigated, i.e. Agilus30 (Stratasys, Minnesota, USA) and Elastic a

In this paper shortwave infrared (SWIR) thermographic measurements of the manufacturing of thin single-line walls via laser metal deposition (LMD) are presented. As the thermographic camera is mounted fixed to the welding arm, an acceleration sensor was used to assist in reconstructing the spatial position from the predefined welding path. Hereby we could obtain data sets containing the size of the molten pool and the oxide covered areas as functions of the position in the workpiece. Furthermore, the influence of the acquisition wave- length onto the thermograms was investigated in a spectral range from 1250 nm to 1550 nm. All wavelengths turned out to be usable for the in-situ process monitoring of the LMD process. The longer wavelengths are shown to be beneficial for the lower temperature range, while shorter wavelengths show more details within the molten pool.

We present the results of a 3D modeling of the laser powder bed fusion process on the mesoscale level with an advanced multiphysical numerical tool. High-performance simula- tion allowed to conduct a vast parametric study. Thus, the model has been extensively verified against experimental results in a large parameter range, and, further, it has been used to con- struct detailed process maps in the range not covered by the available experimental data. The analysis of the results that were obtained in the model along with the data in the pub- lished research allowed to propose the quantitative criteria for determining the behavior of the track formation. The key phenomena that affect this behavior have been studied. We conclude that the productivity limit that arises with the proportional increase in scanning speed and laser beam power is caused by the spatter ejection. The sensitivity analysis shows that the transition to the spattering regime is caused by the overheating of the meltpool surface layer, and, conse- quently, the development of the surface instability. The instability development is assumed to be due to the fact that the recoil pressure becomes much higher in comparison with the surface tension.

In this study, Electron Beam Melting (EBM) is used to produce chiral auxetic lattices, and the compression of chiral auxetic lattice is investigated experimentally and numerically in the edgewise direction, where auxeticity can be experienced. Titanium Alloy (Ti6Al4V) metal- lic powder is used in this study. To understand mechanical behaviour and to characterize EBM printed parts, tensile tests are conducted. According to the tensile test results, a constitutive equation is selected, calibrated and adopted to represent the behaviour of the material. Further- more, a chiral unit cell is manufactured and tested with a compressive load profile to investigate its displacement limit by applying large displacements without experiencing permanent defor- mations, degradation or failures. The same scenarios explored in the experiments are then analyzed by means of non-linear computational models using a commercial finite element code to validate a numerical approach for optimal design and performance prediction.

A finite element model for prediction of the temperatura field in the poder bed fusión process is presented and compared to measurements. Accurate temperatura predictions at the base plate are essential to accurately predict the formation of cristals in a metallic glass forming material. The temperatura measurements were performed by equipping the base plate with thermocouples during manufacturing of a cylinder with the glass forming alloy AMZ4. Boundary conditions for heat losses through the base plate/machine contact interfaces was calibrated to fitthe measurements. Additional heat losses was used to account for radiation at the top Surface and conduction through the poder bed. An interface boundary condition based on conservation of heat flux was examined to match the heat flow to the machine structure and the temperatura predictions was satisfying. Still,temperatura predictions with a constant heat transfer coefficient matched the measurements within 1.5oC during the entire building process of about 9 hours.

This paper presents a methodology to design optimum lattice-like engineering components that can be easily created using additive manufacturing. The optimal performance of the design is assured through a topology optimization, where as the manufacturability is ensured thanks to the lattice nature of the designs. The paper discusses some advantages of lattice topology optimization compared to a traditional topology optimization approach, both in terms of performance and manufacturability of the final designs. The methodology combines different commercial software tools in order to effectively create such designs, that can be used in a wide range of sectors such as automotive, aerospace or medical.

We live in a time where resources are scarce and tools are developed to control their use. One of the most powerful material-saving tools is shape optimization. This latter is a computational method in which the shape of a designed part is adapted by adding or removing material according to the environment in which this part will be used. This method produces complex shapes, difficult to manufacture using classical techniques. In such situations, additive manufacturing appears to be as an appealing approach. In this paper, a non intrusive average stress based shape optimization technique is presented. This technique is composed of a processing phase followed by a post processing smoothing phase. In the processing phase, the stresses in a certain part are calculated using finite elements analysis. Then the Von mises effective stresses are calculated and compared to the average stress in the part. The low stress elements are removed, and hence in each iteration the average stress is changing as well as the standards deviation. After several iterations, the algorithm converges and the part is ready for the post processing phase. In the next phase, the part has non smooth surface because of the element removal. Each node on the non smooth surface is detected and the concavity of the surface to which it belongs is found with respect to the topology of its environment, using a weighted Laplacian algorithm linking the selected node to its neighbors. The obtained concavity is then applied to each node. The process is repeated for several iterations until the surface is smooth as desired and the final shape is found and ready for printing. This technique has been tested on several load configurations and the obtained results were in agreement with other techniques from the open literature [1]. This method is attractive since it doesn’t need to re-mesh the domain at every iteration. In addition, it does not require a high processing power since the results were obtained durin

The urgency of mathematical model development for wire-based electron-beam additive manufacturing process analysis is shown. The procedure of solving heat equation for metal in the solid phase and the Navier-Stokes equations in the liquid phase, based on the use of the finite-difference method and the predictor-corrector procedure is described. An algorithm for numerical approximation of free melt surface motion, using the concept of the volume of fluid (VOF), is described as well. A numerical algorithm for surface tension force calculating is proposed. The model described above was realized as a program in the Microsoft Visual Studio environment. Series of computational experiments were carried out to calculate metal flow during deposition with the use of 316L steel wire. The results of experiments are compared with experimental data.

End-to-End Mission Performance Simulators for Earth Observation missions are one of the prominent tools for system design and scientific validation in early mission phases. The European Space Agency has promoted efforts to exploit synergies between activities and reduce engineering costs in mission planning. The main goal of the BIBLOS project is to provide a library of software units called “Building Blocks”, or simply “Blocks”. These blocks could then be integrated into modules, following the reference architecture developed in the frame of the ARCHEO-E2E project, in order to build an End-to-End Simulator in an efficient manner. The first stage of BIBLOS project, referred to as EOMODEL (or BIBLOS-1) and, focused on Passive Optical instruments, was successfully finished (in April 2016) with the geometry, scene generation and instrument modelling of optical imagers, which are one of the most frequent types of passive optical instrument on Earth Observation satellites. BIBLOS-2, which is the second stage of the BIBLOS project, is a currently finished activity with the purpose of expanding the BIBLOS library to include Passive Microwaves instruments and Active Microwaves instruments. Additionally, as part of a continuous improvement process, this second stage of BIBLOS has also updated some of the most computational performance intensive blocks for Passive Optical instruments with parallel implementation for Graphic Processing Units. For BIBLOS-2, the Sentinel-1 and MicroWave Imager (MWI) instruments have been selected to develop the building blocks for Active Microwaves and Passive Microwaves instruments respectively. During the BIBLOS-2 stage the full simulation chain has been developed for Passive Microwave, starting from the Geometry Module, through Scene Generation and Instrument Modules and ending at Level 1 Processing Module. For Active Microwave Instruments this stage of the BIBLOS activity is focused on the Geometry Module and the Performance Evaluation Modul, BIBLOS-2 Project is led by GMV Innovating Solutions Sp. z o.o. and realized for the European Space Agency under the Contract No. 4000118711/16/NL/AF “Model Library for Earth Observation End-to-End Simulators”., Peer Reviewed, Postprint (published version)

The fatigue behavior of ABS SLM Inconel 718 obtained by testing directionally-fabricated specimens is presented and discussed together with characterization of surface topography of the specimens using green light interferometry.

The selective laser melting process causes high thermal-induced residual stresses that may result in unwanted part distortion and may affect fatigue strength of the part. This study initially presents the fatigue behavior obtained by testing directional specimens of SLM AlSi10Mg in the as-built condition (i.e. no heat treatment after fabrication). Then, the SLM process of specimen fabrication is simulated using the inherent strain approach to determine residual stresses at the location and in the direction of fatigue crack initiation. A direct correlation of the computed residual stresses and the actual fatigue behavior provides qualitative insight into the simulation accuracy.

One important advantage of Additive Manufacturing (AM) in relation to optimization for light weight construction is that there is a reduction in manufacturing constraints compared to classical manufacturing methods [5]. To make full use of these advantages and to exploit the resulting potential, the components previously have to be designed using optimization (see[5]). Against this backdrop, a Mixed Integer Program (MIP) is developed in order to be able to use the methods of Technical Operations Research (TOR) in the context of Topology Optimization (TO) on the basis of a fitted Ground Structure Method (GSM) for lattice and truss structures. In addition, an optimization-oriented construction workflow (see figure 3) is developed in order to fully exploit the advantages in design freedom of AM. As shown in figure 3, this work addresses three interdisciplinary subareas; Operations Research (OR), AM as the manufacturing method and a link between this sub-areas in the form of a Computer Aided Design (CAD) solution, resulting in a TOR application.

Triply periodic minimal surface (TPMS) based geometries exhibit extraordinary mechanical, thermal, electrical and acoustic properties thanks to their unique topologies. There are various types of structures in the TPMS family. One of the most well-known TPMS structures is the gyroid structure. This paper focuses on the vibrational behavior of a novel sandwiched gyroid structure in terms of their natural frequencies and mode shapes with three different feasible unit sizes at same volume ratio. Powder bed fusion technology is employed to fabricate gyroid porous specimens made of HS188 material. Modal testing is performed to deduce the vibration characteristics of aforementioned cellular structures. Besides the experimental study, the dynamic performance of the considered structures is investigated computationally by performing modal analysis using Finite Element (FE) models. A key challenge facing FE modelling of large scale gyroid structure is computation time and accuracy. For that reason, small size of gyroid lattices are utilized for compression tests in order to extract elastic properties. Then sandwiched gyroid plate is modelled as solid body with calculated elastic properties instead of complex gyroid topology and analyzed. Finally correlation level between experimental and FE results are presented.