Products with complicated shapes require superior surface finish to perform the intended function. Despite significant developments in technology, finishing operations are still performed semi automatically/manually, relying on the skills of the machinist. The pressure to produce products at the best quality in the shortest lead time has made it highly inconvenient to depend on traditional methods. Thus, there is a rising need for automation which has become a resource to remain competitive in the manufacturing industry. Diminishing return of trading quality over time in finishing operations signifies the importance of having a pre-determined trajectory (tool path) that produces an optimum surface in the least possible machining time. Tool path optimization for finishing process considering tool kinematics is of relatively low importance in the present scenario. The available automation in grinding processes encompass around the dynamics of machining. In this paper we provide an overview of optimizing the tool path using evolutionary algorithms, considering the significance of process dynamics and kinematics. Process efficiency of the generated tool movements are studied based on the evaluation of relative importance of the finishing parameters. Surface quality is analysed using MATLAB and optimization is performed on account of peak to valley height. Surface removal characteristics are analysed based on process variables that have the most likely impact on surface finish. The research results indicated that tool path is the most significant parameter determining the surface quality of a finishing operation. The inter-dependency of parameters were also studied using Taguchi design of experiments. Possible combinations of various tool paths and tool influencing parameters are presented to realize a surface that exhibits lowest errors. / European Horizon 2020 Project SYMPLEXITY

A utilização mais eficiente dos recursos naturais tem levado a indústria a aumentar a eficiência dos produtos manufaturados. Veículos de transporte Diesel estão incluídos neste cenário. Nos motores Diesel, um componente importante do sistema de injeção é o bico injetor. Uma legislação recente no Brasil introduziu limites de emissões EURO5. Estes novos parâmetros tiveram impacto no projeto do bico injetor com tolerâncias sendo reduzidas, em especial na área da sede do corpo do bico injetor, alterando o parâmetro funcional de pressão de abertura do produto. Neste cenário, o impacto desta superfície cônica retificada sobre a pressão de abertura é grande, bem como, sobre o desempenho do motor Diesel. Este estudo tem como objetivo analisar o defeito de topografia superficial típico e recorrente no processo de retificação interna cônica da sede do corpo dos bicos injetores. Um experimento planejado foi realizado de acordo com método Taguchi e determinou-se a relação sinal-ruído para dois parâmetros de topografia 2D. A superfície da sede também foi analisada utilizando análise topográfica 3D. Os resultados deste estudo incluem a indicação de possíveis causas do defeito recorrente, caracterização dos principais elementos do processo de retificação, caracterização da superfície retificada e otimização dos parâmetros do processo de retificação. / Industries of manufactured products have increased their efficiency optimizing the natural resources usage and Diesel commercial vehicles are included in this scenario. For Diesel engines, one of the most important components of the injection system is the nozzle injector. In Brazil, EURO5 legislation was recently introduced, bringing new emission limits for Diesel engines. Because of this, the nozzle injector design has changed and some manufacturing tolerances were reduced, in special the body seat geometry. This also changed the nozzle opening pressure. In this new process, the body seat grinded conical surface impacts on this functional parameter and consequently the Diesel engine performance. This study has as target to analyze a recurrent defect in the internal conic grinding process of the nozzle body seat. A trial was performed in this process according to Taguchi method and signal / noise ratio for 2D topographic parameters were defined. The body seat surface was also analyzed using 3D topographic analysis. The results of this study include the possible cause of the recurrent failure, characterization of the ground surface, process main elements integrity assessment and optimization of the grinding process parameters.

Abstract In the world where every sector of industrial manufacturing is being converted toautomated systems, surface finishing processes like sanding and polishing seem to lag.This phenomenon is not surprising as these processes are complex to optimize. Therehave been projects going on with the support of European Commission to findsolutions under SYMPLEXITY (Symbiotic Human-Robot Solutions for ComplexSurface Finishing Operations). One of the projects in under this include poliMATIC(Automated Polishing for the European Tooling Industry). Halmstad University isinvolved in doing projects. This project took a portion of this study in aim to understand a foam material’s behavior used for sanding tool at the tip of a robotic arm. This is studied using a forcemeasurement system developed at Halmstad University. The project has two sectionsand starts with one; Understanding the force measurement system and upgrading innecessary ways. Two; studying how the foam material compressive hardness propertyis affected when the material is fit with sandpaper for sanding operation using theforce measurement system. The study finally revealed how the combination of thefoam with sandpaper affects the robustness of the material, and significantlyimproved the output of the system with by reducing the noise level with 40%.

Les résonateurs à modes de galerie sont des cavités diélectriques qui supportent des modes à très haut facteur de qualité et à faible volume qui demeurent confinés à l'interface air-diélectrique pour des durées pouvant atteindre voire dépasser la microseconde. L'intérêt de ce fort confinement des modes pour de longues durées est l'accentuation de l'interaction lumière-matière. Par conséquent, de nombreuses interactions non-linéaires telles que l'effet Kerr ou encore l'effet Brillouin à des puissances seuil inversement proportionnelles au carré voire au cube du facteur de qualité du résonateur ont lieu en son sein. Ces propriétés donnent accès à de nombreuses applications dans des domaines divers et variés tels que la spectroscopie, les télécommunications ou encore les micro-ondes. Les travaux de cette thèse ont pour but d'exploiter les non-linéarités Kerr et Brillouin dans les résonateurs à mode galerie à la longueur d'onde de 1550 nm afin de générer des micro-ondes ultra-stables à des fréquences comprises entre 5 et 30 GHz. Le premier chapitre introduit la théorie, la fabrication, le couplage et la caractérisation de résonateurs à des modes de galerie. Le second chapitre concerne la génération de micro-ondes. Nous y présentons nos résultats expérimentaux, la modélisation numérique de peignes de Kerr, ainsi que l'analyse d'instabilités oscillatoires d'origine thermique observées lors de nos travaux expérimentaux, puis nous concluons. Le dernier chapitre traite de l'interaction photons-phonons via le processus de diffusion Brillouin stimulée dans ces mêmes expérimentaux ainsi que le modèle temporel que nous avons développé pour suivre la dynamique de l'onde transmise et de celle rétrodiffusée. Le dernier chapitre conclue nos travaux. Les travaux présentés dans ce manuscrit ont été financé par l'European Research Council dans le cadre du projet NextPhase. / Whispering galery mode resonators are dielectric cavities that support modes with ultra-high quality factor and small volume that remain confined in their inner periphery for time duratioons that can be as long as few microseconds. The strong confinement of these modes for such long durations strongly enhances nonlinear effect suchs as Kerr effect or Brillouin effect. These resonators can therefore be used for several applications such as spectroscopy, telecommunications or microwave generation. The objective of this thesis is to use Kerr and Brillouin nonlinearities in these resonators at the laser wavelength of 1550 nm, in order to generate high spectral purity microwave signals with frequencies rangong fros 5 to 30 GHz. The first chapter oh the thesis intriduces the theory, fabrication, coupling and characterisation of whispering gallery mode resonators. The second chapter is about the generation of Kerr optical frequency combs in these resonators and their application to the generation of microwave signals. We present our experimental resuktsdn the numerical modelling of Kerr combs, the analysis of oscillatory instabilities (due to thermal effect) observed during our experiments, and conclue. The third chapter concerns photon-phonon interactions via stimulated Brillouin scattering in these resonators and their application to the generation of microwave signals. We present our experimental results and the temporal model that we developed to track the dynamics of the forward and backscattered fields. The last chapter conclude the thesis. The research presented in this thesis has benne funded by the European Research Council through the project Nextphase.

The diploma thesis deals with the problems of pavement surface skid resistence of wearing course of asphalt mixtures with R-material. Specifically, it is a mixture of type ACO 11 (asphalt concrete for wearing layers). In the theoretical part of the thesis there are dismantled the problems of Antiskid properties of the road surface and recycling of R-material. The practical part is dedicated to the design and laboratory production of the asphalt mixture ACO 11 without admixture of R-material and with content of 38 % R-material. In addition, the results of the measurement of friction coefficient after smoothed for these bitumen mixtures are shown in the work. The aim of the thesis was to determine the influence of the increased content of R-material on the anti-skid properties of the road surface as it is planned to update the standard ČSN EN 13108-1, which will allow the use of up to 40 % R-material into the mixtures of type ACO 11.

A novel, environmentally friendly, fast, and flexible polishing process for Nitinol parts is presented in this study. Nitinol samples with both superelastic and shape memory properties at room temperature were investigated. The chemical contamination and surface roughness of superelastic Nitinol plates were examined before and after plasma electrolytic polishing. The shift in phase transformation temperature and tensile strength before and after the polishing process were analysed using Nitinol wire with shape memory properties. The obtained experimental results were compared to the data obtained on reference samples examined in the as-received condition. It was found that plasma electrolytic polishing, when the right process parameters are applied, is capable of delivering Nitinol parts with extremely high surface quality. Moreover, it was experimentally proven that plasma electrolytic polishing does not have a negative impact on functionality or mechanical properties of polished parts.

Tesis por compendio / [ES] El mecanizado con brazos robots ha sido estudiado aproximadamente desde los años 90, durante este tiempo se han llevado a cabo importantes avances y descubrimientos en cuanto a su campo de aplicación. En general, los robots manipuladores tienen muchos beneficios y ventajas al ser usados en operaciones de mecanizado, tales como, flexibilidad, gran área de trabajo y facilidad de programación, entre otras, frente a las Máquinas Herramientas de Control numérico (MHCN) que necesitan de una gran inversión para trabajar piezas muy grandes o incrementar sus grados de libertad. Como desventajas, frente a las MHCN, los brazos robóticos poseen menor rigidez, lo que combinado con las altas fuerzas producidas en los procesos de mecanizado hace que aparezcan errores de precisión, desviaciones en las trayectorias, vibraciones y, por consiguiente, una mala calidad en las piezas fabricadas. Entre los brazos robots, los brazos colaborativos están en auge debido a su programación intuitiva y a sus medidas de seguridad, que les permiten trabajar en el mismo espacio que los operadores sin que estos corran riesgos. Como desventaja añadida de los robots colaborativos se encuentra la mayor flexibilidad que estos tienen en sus articulaciones, debido a que incluyen reductores del tipo Harmonic drive. El uso de un control de fuerza en procesos de mecanizado con brazos robots permite controlar y corregir en tiempo real las desviaciones generadas por la flexibilidad en las articulaciones del robot. Utilizar este método de control es beneficioso en cualquier brazo robot; sin embargo, el control interno que incluyen los robots colaborativos presenta ventajas que permiten que el control de fuerza pueda ser aplicado de una manera más eficiente. En el presente trabajo se desarrolla una propuesta real para la inclusión del control de esfuerzos en el brazo robot, así como también, se evalúa y cuantifica la capacidad de los robots industriales y colaborativos en tareas de mecanizado. La propuesta plantea cómo mejorar la utilización de un control de fuerza por bucle interior/exterior aplicado en un brazo colaborativo cuando se desconocen los pares reales de los motores del robot, así como otros parámetros internos que los fabricantes no dan a conocer. Este bucle de control interior/exterior ha sido utilizado en aplicaciones de pulido y lijado sobre diferentes materiales. Los resultados indican que el robot colaborativo es factible para realizar tales operaciones de mecanizado. Sus mejores resultados se obtienen cuando se utiliza un bucle de control interno por velocidad y un bucle de control externo de fuerza con algoritmos, Proporcional-Integral-Derivativo o Proporcional más Pre-Alimentación de la Fuerza. / [CA] El mecanitzat amb braços robots ha estat estudiat aproximadament des dels anys 90, durant aquest temps s'han dut a terme importants avanços i descobriments en el que fa al seu camp d'aplicació. En general, els robots manipuladors tenen molts beneficis i avantatges al ser usats en operacions de mecanitzat, com ara, flexibilitat, gran àrea de treball i facilitat de programació, entre d'altres, davant de Màquines Eines de Control Numèric (MECN) que necessiten d'una gran inversió per treballar peces molt grans o incrementar els seus graus de llibertat. Com a desavantatges, enfront de les MECN, els braços robòtics posseeixen menor rigidesa, el que combinat amb les altes forces produïdes en els processos de mecanitzat fa que apareguin errors de precisió, desviacions en les trajectòries, vibracions i, per tant, una mala qualitat en les peces fabricades. Entre els braços robots, els braços col·laboratius estan en auge a causa de la seva programació intuïtiva i a les seves mesures de seguretat, que els permeten treballar en el mateix espai que els operadors sense que aquests corrin riscos. Com desavantatge afegida als robots col·laboratius es troba la major flexibilitat que aquests tenen en les seves articulacions, a causa de que inclouen reductors del tipus Harmonic drive. L'ús d'un control de força en processos de mecanitzat amb braços robots permet controlar, i corregir, en temps real les desviacions generades per la flexibilitat en les articulacions del robot. Utilitzar aquest mètode de control és beneficiós en qualsevol braç robot, però, el control intern que inclouen els robots col·laboratius presenta avantatges que permeten que el control de força es puga aplicar d'una manera més eficient. En el present treball es desenvolupa una proposta real per a la inclusió del control d'esforços en el braç robot, així com s'avalua i quantifica la capacitat dels robots industrials i col·laboratius en tasques de mecanitzat. La proposta planteja com millorar la utilització d'un control de força per bucle interior/exterior aplicat en un braç col·laboratiu, quan es desconeixen els parells reals dels motors del robot, així com altres paràmetres interns que els fabricants no donen a conèixer. Aquest bucle de control interior/exterior ha estat utilitzat en aplicacions de polit sobre diferents materials. Els resultats indiquen que el robot col·laboratiu és factible de realitzar aquestes operacions de mecanitzat. Els seus millors resultats s'obtenen quan s'utilitza un bucle de control intern per velocitat i un bucle de control extern de força amb els algoritmes Proporcional-Integral-Derivatiu o Proporcional més Pre-alimentació de la Força. / [EN] Machining with robot arms has been studied approximately since the 90s; during this time, important advances and discoveries have been made in its field of application. In general, manipulative robots have many benefits and advantages when they are used in machining operations, such as flexibility, large work area, and ease of programming, among others, compared to Numerical Control Machine Tools (NCMT) that need a great investment to work very large pieces or increase their degrees of freedom. As for disadvantages, compared to NCMT, robotic arms have lower rigidity, which, combined with the high forces produced in machining processes, causes precision errors, path deviations, vibrations, and, consequently, poor quality in the manufactured parts. Among robot arms, collaborative arms are on the rise due to their intuitive programming and safety measures, which allow them to work in the same space without risk for the operators. An added disadvantage of collaborative robots is their flexibility in their joints because they include Harmonic drive type reducers. The use of force control in machining processes with robot arms makes possible to control and correct, in real-time, the deviations generated by the flexibility in the robot's joints. The use of this control method is beneficial for any robot arm. However, the internal control included in collaborative robots has advantages that allow the force control to be applied more efficiently. In this work, a real proposal is developed to include effort control in the robot arm. The capacity of industrial and collaborative robots in machining tasks is evaluated and quantified. The proposal recommends how to improve the use of an inner/outer force control loop applied in a collaborative arm, when the real torques of the robot's motors are unknown and other internal parameters that manufacturers do not disclose. This inner/outer control loop has been used in polishing and sanding applications on different materials. The results indicate that the collaborative robot is feasible to perform such machining operations. Best results are obtained using an internal velocity control loop and external force control loop with Proportional-Integral-Derivative or Proportional plus Feed Forward. / The authors are grateful for the financial support of the Spanish Ministry of Economy and European Union, grant DPI2016-81002-R (AEI/FEDER, UE). This work was funded by the CONICYT PFCHA/DOCTORADO BECAS CHILE/2017 – 72180157. / Pérez Ubeda, RA. (2022). Propuesta de inclusión de esfuerzos en el control de un brazo robot para asegurar el cumplimiento de la rugosidad superficial durante operaciones de lijado en diferentes materiales [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/182000 / Compendio

The focus of this thesis is on the most commonly used types of stone, the methods of quarrying stone, stone working, the tools developed and used for that purpose, and the ways in which stone was transported and hoisted into place. This is starting from the earliest times in which large temples or buildings were constructed, namely the Neolithic, up till the time of the Roman Empire. Besides being a kind of compendium of most aspects of stone working, which could be found, also attention is given to the ideal conditions under which the construction of a large temple or monument could take place. The framework, which is developed from the description of the construction of Solomon’s Temple in Jerusalem in I Kings 5 and I Chronicles 28, is used to analyse the construction of a number of other temples in different times, places and settings, and with the use of different materials, to test if the framework is applicable in all these situations. Moreover, also other aspects of stone working, such as mosaics and the manufacturing of stone vessels in Jerusalem are described and analysed as to their origins and uses. The intention is to give an overview of the many ways in which stone has been used, so that the reader can get an idea of how large temples and monuments were built and to gain an understanding of what kind of technical know-how and ingenuity existed in antiquity. / Religious Studies and Arabic / D. Phil. (Religious Studies (Biblical Archaeology))

La présente étude porte sur le comportement mécanique de deux types de supports de catalyseurs utilisés industriellement en hydrotraitement des résidus. Ces supports extrudés, fabriqués par IFPEN, sont constitués d’alumine de transition γ avec un taux de porosité proche de 70%. La porosité du premier matériau est uniquement constituée de mésopores (< 50 nm). La porosité du second matériau est constituée de mésopores et de macropores (jusqu’à 20 µm). Les niveaux de sollicitation en service étant très peu connus, cette étude s’attache à décrire de manière précise et exhaustive le comportement mécanique de ces supports sous une large gamme de sollicitations, et à identifier les différents mécanismes de ruine possibles. L’objectif final est de mieux comprendre les relations entre les paramètres microstructuraux et les propriétés mécaniques afin d’identifier des leviers d’amélioration de la tenue mécanique des supports. Dans un premier temps, une méthodologie adaptée de caractérisation mécanique est établie. Le comportement des supports est étudié d’une part en traction, à l’aide d’essais de flexion trois points et d’écrasement diamétral, et d’autre part, en compression sous différents taux de triaxialité, à l’aide d’essais de compression uniaxiale et hydrostatique et d’essais de micro-indentation sphérique. Les différents mécanismes responsables de la ruine des supports sont identifiés au moyen de techniques d’imagerie telles que la microscopie électronique à balayage et la micro-tomographie à rayons X. En traction, le comportement est fragile avec l’amorçage de la rupture sur un défaut critique. En compression, une transition fragile / quasi-plastique du comportement est observée avec l’augmentation du taux de confinement. Cette quasi-plasticité s’exprime en particulier à travers un phénomène de densification de la macroporosité. Dans un deuxième temps, un critère de rupture est identifié pour chaque type de matériau en vue de représenter sur une même surface de charge les différents types de comportement et phénomènes physiques observés. Cette identification est réalisée en couplant les essais d’indentation sphérique à une analyse numérique. Des critères faisant intervenir la pression hydrostatique permettent de rendre compte de la forte dissymétrie du comportement des matériaux en traction et en compression. Enfin, dans un souci de se rapprocher des sollicitations subies par les supports de catalyseurs dans un réacteur en service, le comportement d’un empilement de supports est étudié en compression œdométrique. L’analyse de cet essai par tomographie à rayons X permet de déterminer les différents mécanismes de ruine intervenant au sein d’un empilement, en particulier ceux responsables de la génération de fines. Les résultats illustrent la pertinence de la caractérisation en flexion et en indentation des supports de catalyseurs seuls pour prévoir leur comportement au sein d’un empilement en compression. / In this work, we study the mechanical behaviour of two types of catalysts supports produced by IFPEN and industrially used in residues hydrotreating. Those extruded supports are made of transition γ-alumina with about 70% of porous volume. The first material’s porosity is exclusively composed of mesopores (< 50 nm). The porosity of the second material is composed of both mesopores and macropores (up to 20 µm). Because of the limited knowledge of the stress fields in embedded catalysts supports in use in a reactor, this study aims at precisely and exhaustively describing the mechanical behaviour of those supports under a wide range of stresses, and identifying the possible damage mechanisms. The final objective is to better understand the influence of microstructural parameters on the mechanical properties of the supports in order to propose some leads about how to improve their mechanical strength. First, an adequate mechanical characterization methodology is set. On one hand, the tensile mechanical behaviour of the supports is studied with three-point bending and diametrical crushing tests. On the other hand, their compressive behaviour under various triaxiality rates is characterized in uniaxial and hydrostatic compression, and by spherical micro-indentation. The different damaging mechanisms are identified by imaging techniques such as scanning electronic microscopy and X-ray micro-tomography. Under tensile stresses, the supports exhibit a brittle behaviour and fracture initiates at a critical flaw. Under compressive stresses, a brittle/quasi-plastic transition is observed with increasing the triaxiality rate. The quasi-plasticity is mainly due to the densification of the macroporosity. The second part of the study consists in identifying, for each material, a fracture criterion able to represent every types of behaviour and physical phenomena observed on the same yield surface. This identification is achieved by coupling the spherical indentation tests to a numerical analysis. Fracture criteria involving hydrostatic pressure are well suited to describe the highly dissymmetric mechanical behaviour of the materials in tension and in compression. The last part of this work aims at studying the mechanical behaviour of a stack of supports under œdometric compression in order to produce stress fields more representative of those existing within the supports stacked in a reactor. This test is analysed by X-ray tomography, which allows us to determine/acknowledge the different damaging mechanisms involved in fragments and fines generation. The results illustrate the suitability of the bending and indentation tests to characterize the mechanical properties of a single support and relate them to its mechanical behaviour in a stack of supports under compression.