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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Um sistema de auxílio ao projetista de peças fundidas através da integração entre a técnica DFM e projeto auxiliado por computador / not available

Silva, Alex Sander Chaves da 14 May 2002 (has links)
Um sistema composto por orientações de projeto e de processo, por um software CAD, mais especificamente, pelo PRO-ENGINEER (PRO-E) e um sistema de auxílio voltado para a manufatura (SEMF) foi desenvolvido como forma de auxílio ao engenheiro projetista no desenvolvimento do projeto de peças fundidas em areia. Este sistema integrado é capaz de analisar um desenho feito em sistema CAD (PRO-E), de um modelo de uma peça a ser fundida e fornecer um diagnóstico sobre possíveis violações quanto à sua manufatura. Isto é feito através de uma base de conhecimento que reúne informações de como minimizar possíveis defeitos com relação à geometria da peça a o processo de fundição. O desenho deve seguir um procedimento adequado para que as features criadas no PRO-E possam ser reconhecidas pelo sistema, para um possível diagnóstico de problemas existentes na geometria da peça e/ou no processo de fundição. / A computer system based on design and process guidelines and a CAD system has been developed in order to aid an engineer designer to develop cast parts free from defects. The proposed system can analyze and detect, automatically, problems that may happen during the casting process of a part. This is done through a built-in Knowledge Base that gather information on how to avoid defects related to part geometry and casting process. The parts must be designed using the CAD system, PRO-E, and the drawing of the part, must be done following a certain procedure, otherwise the system will not be able to check the part.
22

Um sistema de auxílio ao projetista de peças fundidas através da integração entre a técnica DFM e projeto auxiliado por computador / not available

Alex Sander Chaves da Silva 14 May 2002 (has links)
Um sistema composto por orientações de projeto e de processo, por um software CAD, mais especificamente, pelo PRO-ENGINEER (PRO-E) e um sistema de auxílio voltado para a manufatura (SEMF) foi desenvolvido como forma de auxílio ao engenheiro projetista no desenvolvimento do projeto de peças fundidas em areia. Este sistema integrado é capaz de analisar um desenho feito em sistema CAD (PRO-E), de um modelo de uma peça a ser fundida e fornecer um diagnóstico sobre possíveis violações quanto à sua manufatura. Isto é feito através de uma base de conhecimento que reúne informações de como minimizar possíveis defeitos com relação à geometria da peça a o processo de fundição. O desenho deve seguir um procedimento adequado para que as features criadas no PRO-E possam ser reconhecidas pelo sistema, para um possível diagnóstico de problemas existentes na geometria da peça e/ou no processo de fundição. / A computer system based on design and process guidelines and a CAD system has been developed in order to aid an engineer designer to develop cast parts free from defects. The proposed system can analyze and detect, automatically, problems that may happen during the casting process of a part. This is done through a built-in Knowledge Base that gather information on how to avoid defects related to part geometry and casting process. The parts must be designed using the CAD system, PRO-E, and the drawing of the part, must be done following a certain procedure, otherwise the system will not be able to check the part.
23

Produktanpassning vid insourcing av bearbetning : Tillverkningsanpassad konstruktion och insourcing i produktutvecklingsprocessen

Karlsson, David January 2017 (has links)
Hög produktkvalitet och låg tillverkningskostnad är avgörande för den ekonomiska framgången för en produkt, och för att uppnå en sådan framgång används metoden tillverkningsanpassad konstruktion (DFM). DFM är en väldigt integrativ metod och kräver ett tvärfunktionellt arbete mellan experter så som produktionstekniker, produktionsberedare och tillverkningspersonal (Ulrich & Eppinger, 2014). Volvo CE har ett kontinuerligt arbete med DFM och det utförs idag genom många iterationer och direkt kontakt mellan tillverknings- och utvecklingsavdelningen. Trots det kontinuerliga arbetet med DFM eftersöker nu avdelningen Driveline Systems Product Improvement en metod för detta arbete, eftersom att ingen metod används idag. Metoder för DFM finns beskrivna på flera olika sätt och av flera olika författare, och i detta arbete undersöks metoder av Ulrich & Eppinger (2014), Dalton et al. (2016) and O’Driscoll (2002). En standardiserad metod och ett överskådligt arbete med DFM kan skapa bättre förutsättningar för kunskapsåterföring för att se och lära från tidigare arbeten kopplat till tillverkning av produkterna. Samtidigt som en DFM-metod efterfrågas undersöks Volvos nuvarande produktutvecklingsprocess, DMAIC, på den aktuella avdelningen, som idag är anpassad till utveckling och förbättringar av befintliga artiklar. För det aktuella ärendet är orsaken att öka beläggningen och genomförandet föregås således inte av någon förbättring eller utveckling av artiklarna. Därför ska det aktuella insourcing-ärendet jämföras mot Volvos egna process. För att knyta an det aktuella ärendet till vedertagna produktutvecklingsprocesser används en teoretisk produktutvecklingsprocess, och ärendet jämförs även mot denna process. I arbetet utförs fältarbete, inklusive fallstudier och intervjuer, samt en kompletterande litteraturstudie runt metoden DFM och insourcing. I fältarbetet undersöks två externt tillverkade artiklar som två fall som väljs ut genom ett projektval, vari totalt sex artiklar ingår från början. För att genomföra projektvalet och vidare utveckling av artiklarna tillämpades i huvudsak Ullmans (2010) produktutvecklingsprocess med tillhörande metoder (relevanta för detta arbete), med något inslag av Ulrich & Eppingers (2014) process. Utifrån den eftersökta metoden för arbete med DFM, och aktuella fallstudier och processer ska följande frågor besvaras:   Hur korrelerar en insourcing-process med teoretiska produktutvecklingsprocesser och Volvos produktutvecklingsprocess? I vilka steg i insourcing-processen är det relevant att inkludera DFM?   Aspekter kopplat till tillverkningsanpassad konstruktion, och således DFM, är aspekter som påverkar tillverkningskostnaden. Vid insourcing är förädlingskostnaden och skiftgraden de mest relevanta och kanske viktigaste aspekterna, som bör adresseras redan i projektvalet. Både förädlingskostnaden och skiftgraden är aspekter som påverkar tillverkningskostnaden. Vid insourcing är det dessutom viktigt att beakta orsaker till outsourcing, som inte framgår i varken processen DMAIC eller Ullmans (2010) process. Kopplat till processerna jämfört med insourcing-ärendet så förekommer vissa skillnader mellan både Ullmans (2010) produktutvecklingsprocessen och Volvos process DMAIC, även om en del likheter också finns. / High product quality together with low manufacturing cost are vital aspects of the economic success of a product. To achieve such success the method Design for Manufacturing (DFM) is used. DFM is a highly integrative method and demands a cross-functional team consisting of experts such as production engineers, pre-process engineers and manufacturing personnel (Ulrich & Eppinger, 2014). Volvo CE has a continuous work with DFM and it is done through many iterations and direct contact between the manufacturing- and design department. Although the overall work with DFM is continuous the department Driveline Systems Product Improvement is requesting a method for this work, due to the lack of any methods used today. It is discovered that there are many different methods for DFM described by many authors, and in this thesis methods by Ulrich & Eppinger (2014), Dalton et al. (2016) and O’Driscoll (2002) are investigated. A standardized way may increase the quality of the DFM work and may help create a more holistic view. A holistic view over the work with DFM can help create better conditions for re-use of previous knowledge related to manufacturing of the parts. In addition of the requested method for DFM the current product development process used, DMAIC, is investigated. The process is today mainly used and adapted for the development and improvement of existing products. The reason of the current case studies is to increase the utilization level at the current manufacturing department, and thus no improvement or development is initially present. Therefore, the current insourcing case studies are compared to the Volvo process DMAIC. To connect the current case to established product development processes the case studies are also compared to a theoretical product development process.   Methods used within this thesis are field work, with interviews and case studies, and a complementary literature study to investigate methods and to increase the understanding of DFM and insourcing. In the field work two parts for insourcing are investigated as two case studies. The parts are initially selected through a project selection, where a total of six parts are included. To perform the selection and further development of the current case studies Ullmans (2010) design process were applied, with use of relevant methods and tools for this work. Also, some elements of the product development process according to Ulrich & Eppinger (2014) were applied. Based on the requested method for DFM and the current case studies the following research questions were raised:   How does an insourcing process correlate with theoretical design processes and with Volvo’s product development process? Where in the insourcing process is it relevant to include DFM?   Aspects of DFM are aspects that affect the manufacturing cost. When insourcing processing of parts and labour shift rate are the most relevant and important aspects and should be addressed when selecting and evaluating project. Both processing of parts and labour shift rate are aspects that affect the manufacturing cost. When insourcing it is also important to include aspects connected to outsourcing, and this fact cannot be identified in the DMAIC process nor the design process of Ullman (2010). Compared to the current insourcing case studies there are some differences between both the design process of Ullman (2010) and the Volvo process DMAIC, even if there also are some similarities.
24

Creating Total Value Engineering Through Combining Design for Manufacturing and Design for Six Sigma Constructs

Christensen, David Ryan 08 July 2014 (has links) (PDF)
The modern manufacturing world has been driven to compete in a more international and interconnected system. This has led to increased focus upon frameworks and architectures to guarantee quality, high market acceptance, and reduce cost. Modern manufacturing design processes evolved largely from Henry Ford at Ford Motor Company, and Alfred Sloan at General Motors. Their structures embody two different focuses on quality and value engineering which have influenced many recent design frameworks. In the 1970s a heavy emphasis was placed upon Design for Manufacturing, which uses group technology, commonality of processes, and continual focus to reduce part count. Some companies have desired a design process that better accounts for new market needs and Voice of the Customer changes, allowing them to break out of the old processes by using a new framework called Design for Six Sigma. Contextual and survey analysis contrasting DFSS and DFM showed these systems have different definitions of what creates value; which causes a different focus on how to improve value. As the market frequently errs at knowing when to apply DFM or DFSS, using a simple case study of a product with high part and assembly cost, teams were challenged to create a better flashlight using both DFM for part reduction, and DFSS for function improvement. The aim was to increase value. Value has been defined by the formula: value = (performance + capability) / cost or as value = function/cost. Results from the case study combining DFM and DFSS constructs demonstrate a total value engineering construct. It was also shown that DFM indicated effectiveness for a slow-changing market with cost reduction focus, and DFSS demonstrated effectiveness for analyzing continually changing market needs. Disruptive innovations can replace a formerly lull market, for which DFM can be completely unprepared; while DFSS is not effective in slow product-change markets. Incorporating the best of DFSS and DFM creates a Total Value Engineering framework.
25

Systematic Feature Extraction and Feature-based Manufacturing Process Selection for Hybrid Manufacturing

Jha, Smriti 22 August 2022 (has links)
No description available.
26

Organização de conhecimento e informações para integração de componentes em um arcabouço de projeto orientado para a manufatura

Ramos, André Luiz Tietböhl January 2015 (has links)
A constante evolução de métodos, tecnologias e ferramentas associadas na área de projeto fornece maior capacidade para o projetista. Entretanto, ela também aumenta os requisitos de interfaces e controle do conjunto de componentes de projeto consideravelmente. Tipicamente, este aspecto está presente na área de Projeto Orientado para a Manufatura (DFM) onde existem diversos distintos componentes. Cada um dos componentes existentes, ou futuros, pode ter foco diferente, consequentemente com requisitos de informação, utilização e execução distintos. Este trabalho propõe a utilização de padrões conceituais flexíveis de informação e controle de forma abrangente em uma arquitetura de Projeto Orientado para a Manufatura (DFM). O objetivo principal é auxiliar a análise e resolução de DFM, bem como dar suporte à atividade de projeto estruturando e propondo uma solução em relevantes aspectos em DFM: estruturação do contexto das informações (ou conhecimento) em DFM. A arquitetura utiliza as seguintes atividades de projeto em processos de usinagem: Tolerância, Custo, Acessibilidade da ferramenta, Disponibilidade de máquinas e ferramentas e Análise de materiais para demonstrar a relevância da correta contextualização e utilização da informação no domínio DFM . Sob forma geral, concomitantemente, as amplas necessidades de compreensão dos distintos tipos e formas da informação em DFM demandam que uma arquitetura de projeto tenha capacidade de gerenciar/administrar diferentes contextos de informações de projeto. Este é um tópico relevante tendo em vista que existem diferentes atividades DFM que eventualmente devem ser incluídas no ato de projetar. Tipicamente, cada uma delas tem requisitos distintos em termos de dados e conhecimento, ou contextualização do projeto, que idealmente poderiam ser gerenciados através da arquitetura de informação atual – STEP.Aarquitetura proposta gerencia contextos de informações de projeto através de ontologias direcionadas no domínio DFM. Através dela, será possível compreender e utilizar melhor as intrínsecas interfaces existentes nas informações deste domínio, além de, através disto, aumentar a flexibilidade e eficácia de sistemas DFM. / This work proposes the use of industry standards to support the utilization of Design for Manufacturing (DFM) techniques in a comprehensive scale in the design field. The specific aspect being considered in an architecture is the definition and structure of DFM information context. In order to demonstrate the research concepts, some design activities are implemented the framework (which is focused in machining processes): Tolerancing model, Cost model based on material remove processes, Tool Accessibility model taking into consideration the part being designed, Availability of Machines and Tools model, and Material analysis. The broad needs of design–based frameworks, in general, require that its architecture must have the capabilities to handle di erent framework design information utilization contexts, or information context concepts. This is a relevant aspect since there are severalDFMcomponents/activities that preferably should be included in the design process. Traditionally, each one of them might have distinct data & knowledge requirements, which can be handled by the current information architecture – STEP – only in part. Additionally, each one of them might have, or need, di erent forms of understanding DFM information (information context). The framework handles information context concepts through the use of the ontologies targeted to the DFMfield. It is expected that a better comprehension and usage of the intrinsic information interfaces existent in its domain be achieved. Through it, more flexible and e ective DFM systems information-wise can be obtained.
27

Lithography variability driven cell characterization and layout optimization for manufacturability

Ban, Yong Chan 31 May 2011 (has links)
Standard cells are fundamental circuit building blocks designed at very early design stages. Nanometer standard cells are prone to lithography proximity and process variations. How to design robust cells under variations plays a crucial role in the overall circuit performance and yield. This dissertation studies five related research topics in design and manufacturing co-optimization in nanometer standard cells. First, a comprehensive sensitivity metric, which seamlessly incorporates effects from device criticality, lithographic proximity, and process variations, is proposed. The dissertation develops first-order models to compute these sensitivities, and perform robust poly and active layout optimization by minimizing the total delay sensitivity to reduce the delay under the nominal process condition and by minimizing the performance gap between the fastest and the slowest delay corners. Second, a new equivalent source/drain (S/D) contact resistance model, which accurately calculates contact resistances from contact area, contact position, and contact shape, is proposed. Based on the impact of contact resistance on the saturation current, robust S/D contact layout optimization by minimizing the lithography variation as well as by maximizing the saturation current without any leakage penalty is performed. Third, this dissertation describes the first layout decomposition methods of spacer-type self-aligned double pattering (SADP) lithography for complex 2D layouts. The favored type of SADP for complex logic interconnects is a two-mask approach using a core mask and a trim mask. This dissertation describes methods for automatically choosing and optimizing the manufacturability of base core mask patterns, generating assist core patterns, and optimizing trim mask patterns to accomplish high quality layout decomposition in SADP process. Fourth, a new cell characterization methodology, which considers a random (line-edge roughness) LER variation to estimate the device performance of a sub-45nm design, is presented. The thesis systematically analyzes the random LER by taking the impact on circuit performance due to LER variation into consideration and suggests the maximum tolerance of LER to minimize the performance degradation. Finally, this dissertation proposes a design aware LER model which claims that LER is highly related to the lithographic aerial image fidelity and the neighboring geometric proximity. With a new LER model, robust LER aware poly layout optimization to minimize the leakage power is performed. / text
28

Organização de conhecimento e informações para integração de componentes em um arcabouço de projeto orientado para a manufatura

Ramos, André Luiz Tietböhl January 2015 (has links)
A constante evolução de métodos, tecnologias e ferramentas associadas na área de projeto fornece maior capacidade para o projetista. Entretanto, ela também aumenta os requisitos de interfaces e controle do conjunto de componentes de projeto consideravelmente. Tipicamente, este aspecto está presente na área de Projeto Orientado para a Manufatura (DFM) onde existem diversos distintos componentes. Cada um dos componentes existentes, ou futuros, pode ter foco diferente, consequentemente com requisitos de informação, utilização e execução distintos. Este trabalho propõe a utilização de padrões conceituais flexíveis de informação e controle de forma abrangente em uma arquitetura de Projeto Orientado para a Manufatura (DFM). O objetivo principal é auxiliar a análise e resolução de DFM, bem como dar suporte à atividade de projeto estruturando e propondo uma solução em relevantes aspectos em DFM: estruturação do contexto das informações (ou conhecimento) em DFM. A arquitetura utiliza as seguintes atividades de projeto em processos de usinagem: Tolerância, Custo, Acessibilidade da ferramenta, Disponibilidade de máquinas e ferramentas e Análise de materiais para demonstrar a relevância da correta contextualização e utilização da informação no domínio DFM . Sob forma geral, concomitantemente, as amplas necessidades de compreensão dos distintos tipos e formas da informação em DFM demandam que uma arquitetura de projeto tenha capacidade de gerenciar/administrar diferentes contextos de informações de projeto. Este é um tópico relevante tendo em vista que existem diferentes atividades DFM que eventualmente devem ser incluídas no ato de projetar. Tipicamente, cada uma delas tem requisitos distintos em termos de dados e conhecimento, ou contextualização do projeto, que idealmente poderiam ser gerenciados através da arquitetura de informação atual – STEP.Aarquitetura proposta gerencia contextos de informações de projeto através de ontologias direcionadas no domínio DFM. Através dela, será possível compreender e utilizar melhor as intrínsecas interfaces existentes nas informações deste domínio, além de, através disto, aumentar a flexibilidade e eficácia de sistemas DFM. / This work proposes the use of industry standards to support the utilization of Design for Manufacturing (DFM) techniques in a comprehensive scale in the design field. The specific aspect being considered in an architecture is the definition and structure of DFM information context. In order to demonstrate the research concepts, some design activities are implemented the framework (which is focused in machining processes): Tolerancing model, Cost model based on material remove processes, Tool Accessibility model taking into consideration the part being designed, Availability of Machines and Tools model, and Material analysis. The broad needs of design–based frameworks, in general, require that its architecture must have the capabilities to handle di erent framework design information utilization contexts, or information context concepts. This is a relevant aspect since there are severalDFMcomponents/activities that preferably should be included in the design process. Traditionally, each one of them might have distinct data & knowledge requirements, which can be handled by the current information architecture – STEP – only in part. Additionally, each one of them might have, or need, di erent forms of understanding DFM information (information context). The framework handles information context concepts through the use of the ontologies targeted to the DFMfield. It is expected that a better comprehension and usage of the intrinsic information interfaces existent in its domain be achieved. Through it, more flexible and e ective DFM systems information-wise can be obtained.
29

Organização de conhecimento e informações para integração de componentes em um arcabouço de projeto orientado para a manufatura

Ramos, André Luiz Tietböhl January 2015 (has links)
A constante evolução de métodos, tecnologias e ferramentas associadas na área de projeto fornece maior capacidade para o projetista. Entretanto, ela também aumenta os requisitos de interfaces e controle do conjunto de componentes de projeto consideravelmente. Tipicamente, este aspecto está presente na área de Projeto Orientado para a Manufatura (DFM) onde existem diversos distintos componentes. Cada um dos componentes existentes, ou futuros, pode ter foco diferente, consequentemente com requisitos de informação, utilização e execução distintos. Este trabalho propõe a utilização de padrões conceituais flexíveis de informação e controle de forma abrangente em uma arquitetura de Projeto Orientado para a Manufatura (DFM). O objetivo principal é auxiliar a análise e resolução de DFM, bem como dar suporte à atividade de projeto estruturando e propondo uma solução em relevantes aspectos em DFM: estruturação do contexto das informações (ou conhecimento) em DFM. A arquitetura utiliza as seguintes atividades de projeto em processos de usinagem: Tolerância, Custo, Acessibilidade da ferramenta, Disponibilidade de máquinas e ferramentas e Análise de materiais para demonstrar a relevância da correta contextualização e utilização da informação no domínio DFM . Sob forma geral, concomitantemente, as amplas necessidades de compreensão dos distintos tipos e formas da informação em DFM demandam que uma arquitetura de projeto tenha capacidade de gerenciar/administrar diferentes contextos de informações de projeto. Este é um tópico relevante tendo em vista que existem diferentes atividades DFM que eventualmente devem ser incluídas no ato de projetar. Tipicamente, cada uma delas tem requisitos distintos em termos de dados e conhecimento, ou contextualização do projeto, que idealmente poderiam ser gerenciados através da arquitetura de informação atual – STEP.Aarquitetura proposta gerencia contextos de informações de projeto através de ontologias direcionadas no domínio DFM. Através dela, será possível compreender e utilizar melhor as intrínsecas interfaces existentes nas informações deste domínio, além de, através disto, aumentar a flexibilidade e eficácia de sistemas DFM. / This work proposes the use of industry standards to support the utilization of Design for Manufacturing (DFM) techniques in a comprehensive scale in the design field. The specific aspect being considered in an architecture is the definition and structure of DFM information context. In order to demonstrate the research concepts, some design activities are implemented the framework (which is focused in machining processes): Tolerancing model, Cost model based on material remove processes, Tool Accessibility model taking into consideration the part being designed, Availability of Machines and Tools model, and Material analysis. The broad needs of design–based frameworks, in general, require that its architecture must have the capabilities to handle di erent framework design information utilization contexts, or information context concepts. This is a relevant aspect since there are severalDFMcomponents/activities that preferably should be included in the design process. Traditionally, each one of them might have distinct data & knowledge requirements, which can be handled by the current information architecture – STEP – only in part. Additionally, each one of them might have, or need, di erent forms of understanding DFM information (information context). The framework handles information context concepts through the use of the ontologies targeted to the DFMfield. It is expected that a better comprehension and usage of the intrinsic information interfaces existent in its domain be achieved. Through it, more flexible and e ective DFM systems information-wise can be obtained.
30

Intégration des contraintes d’industrialisation des pièces en matériaux composites pour l’aide à la décision en conception préliminaire appliquée au procédé RTM

Mouton, Serge 21 May 2010 (has links)
L’intégration des contraintes d’industrialisation, des pièces en matériaux composites, en conception préliminaire, est un enjeu majeur de la compétitivité des entreprises, et s’inscrit dans une démarche de développement durable. Un travail de captation et de mise en forme de la connaissance industrielle a permis de développer une stratégie d’optimisation. Cette stratégie repose sur une approche multi-métiers, elle permet d’estimer la performance technique et économique d’une solution d’industrialisation. L’estimation de la performance est basée sur l’évaluation, pour chaque solution d’industrialisation, du risque de rupture du composant assemblé, du niveau d’intégration fonctionnelle et du coût de fabrication. La définition de la meilleure alternative est obtenue par la comparaison de la performance de solutions et s’appuie sur des méthodes et outils d’aide à la décision. Le risque de rupture est estimé à partir des écarts entre des caractéristiques de la pièce fabriquée par procédé Resin Transfer Molding (RTM) et les caractéristiques nominales. Les caractéristiques de la pièce fabriquée prises en compte sont : - les écarts géométriques, - les écarts de caractéristiques mécaniques. Dans l’industrie aéronautique, certaines pièces de structure en matériaux composites sont réalisées par le procédé RTM. Dans ce type de mise en forme, les caractéristiques mécaniques du composant sont directement liées au niveau d’imprégnation de la préforme. Dans le travail de thèse, les défauts d’imprégnation sont identifiés comme des écarts volumiques d’imprégnation. Ces écarts ont pour conséquence d’altérer les propriétés mécaniques du matériau qui constitue la pièce. L’estimation des écarts volumiques d’imprégnation est obtenue à partir de l’analyse des résultats de la simulation par éléments finis de l’écoulement de résine dans le renfort fibreux (logiciel Pam RTM®). La géométrie de la pièce obtenue par procédé RTM diffère de la géométrie nominale, cet écart est due en partie aux différences entre les caractéristiques physiques des constituants du matériau composite. Les variations géométriques de la pièce fabriquée sont identifiées comme des écarts géométriques de fabrication. Les écarts géométriques sont compensés, lors de la phase d’assemblage, par des déformations garantissant les contacts avec les pièces adjacentes. Ces déformations génèrent un état de contraintes mécaniques au sein de la pièce. La quantification de l’état de contraintes mécaniques est obtenue à partir d’une simulation thermomécanique par éléments finis réalisée par le logiciel Samcef®. L’aide à la décision est basée sur l’étude combinée de l’état de contraintes mécaniques due à la compensation des écarts géométriques et de l’incidence des écarts volumiques d’imprégnation sur les propriétés mécaniques de la pièce. Trois critères permettent d’estimer le risque de rupture du composant assemblé : un critère de rupture des matériaux composites quantifie le risque de rupture, les deux autres critères, prenant en compte les défauts d’imprégnation, majorent le risque de rupture. Afin de faciliter l’interprétation des résultats et la phase de comparaison de solutions, le risque de rupture est présenté sous forme d’une cartographie. En fonction des couplages des valeurs des critères, une optimisation de la conception et/ou de l’industrialisation est proposée. Une évaluation du niveau d’intégration fonctionnelle ainsi que du coût de fabrication complète la démarche d’aide à la décision. / Integrating industrialization constraints of composite materials into preliminary design is a major challenge for companies in terms of competitiveness, and is part of a sustainable development approach. Work on capturing and formatting industry knowledge has helped develop a design optimization strategy. This strategy is based on multidisciplinary rules, and estimates the technical and economic performance of an industrialization solution. This estimate is based on the evaluation of failure risk of component assembly, level of functional integration and manufacturing cost. The definition of the best alternative is obtained by comparing solution performances, relying on decision support methods and tools. The failure risk is estimated from differences between the characteristics of the part manufactured by Resin Transfer Molding Process (RTM) and the nominal part (CAD). The following characteristics of the manufactured part are taken into account: ? - geometric deviations, ? - characteristic mechanical deviations. In the aviation industry, some structural composite parts are manufacture by RTM. In this type of manufacture, the mechanical properties of the component are directly related to the level of preform impregnation. In this thesis, the impregnation defects are identified as volumic impregnation deviations. These deviations have the effect of altering the mechanical properties of material. Estimated volume impregnation deviations are obtained by analysing the results of the finite element simulation of resin flow into the fibrous reinforcement (software Pam RTM ®). The part geometry obtained using the RTM process differs from the nominal geometry, with the deviation due partly to differences between the physical components of the composite material. The geometric variations in the manufactured part are identified as geometric manufacturing deviations. These geometric deviations are offset, in the assembly phase, by deformations due to contact with adjacent parts, which generate a state of mechanical stress within the part. The mechanical stress state is quantified from a finite element thermomechanical simulation carried out using the Samcef ® software. Decision support is based on the combined study of the state of mechanical stress due to the compensation of geometric deviations and the incidence of volume impregnation deviations on the mechanical properties of the part. Three criteria are used to estimate the failure risk of the assembled component: a composite materials failure criterion quantifies failure risk; the other two criteria, taking into account the impregnation defects, increase the failure risk. To facilitate interpretation of results and the solution comparison phase, the failure risk is represented by mapping. Depending on the coupling values of the criteria, optimizing the design and/or industrialization is proposed. An evaluation of the level of functional integration and manufacturing cost complete the decision support process.

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