Peen forming é um processo de conformação plástica a frio de laminas ou painéis metálicos através do impacto de um jato regulado de pequenas esferas de aço em sua superfície, a fim de produzir uma curvatura pré-determinada. A aplicação da técnica de shot peening como um processo de conformação já é conhecida da indústria desde a década de 1940, mas a demanda crescente por produtos de grande confiabilidade tem impulsionado o desenvolvimento de novas pesquisas visando o seu aperfeiçoamento e automação. . O planejamento do processo de peen forming requer medição e controle de diversas variáveis relacionadas à dinâmica do jato de granalhas e à sua interação com o material a ser conformado. Conforme demonstrado por diversos autores, a velocidade de impacto é uma das variáveis que mais contribui para a formação do campo de tensões residuais que leva o material a se curvar. Neste trabalho é apresentado um modelo dinâmico simplificado que descreve o movimento de um grande número de pequenas esferas arrastadas por um fluxo de ar em regime permanente e sujeitas a múltiplas colisões entre si e com a peça a ser conformada. Simulações deste modelo permitiram identificar a correlação entre o campo de velocidades das granalhas e os demais parâmetros do processo. Mediante a aplicação da técnica de projeto de experimentos pôde-se estimar os valores dos parâmetros que otimizam o processo. Ao final, elaborou-se um algoritmo que permite realizar o planejamento de processos de peen forming, ou seja, determinar os valores desses parâmetros, de modo tal a produzir uma curvatura pré-determinada em uma placa metálica originalmente plana. / Peen forming is a plastic cold work process of shaping a metallic sheet or panel through the impact of a regulated blast of small round steel shots on its surface, in order to produce a previously desired curvature. The application of the shot peening as a forming process has been a known technique in the industry since the decade of 1940, but the increasing demand for products of high reliability have pushed the development of new research in order to enhance and automate it. Peen forming process planning requires the measurement and control of several variables concerning the dynamics of the shot jet and its interaction with the piece to be shaped. As previously shown by several authors, impact velocity is one of the variables that most contribute to the development of the residual stress field that causes the material to bend. In this article we present a simplified dynamical model describing the motion of a large number of small spheres (shot) dragged by an air flow in steady conditions and exposed to multiple collisions with each other and with the piece to be shaped. Computer simulations of this model allowed to identify correlations between the shot field velocity and the parameters of the process. Applying design of experiments techniques it was possible to estimate the value of parameters that optimize the process. It was, then, elaborated an algorithm that enables peen forming process planning, allowing the determination of the parameters, in order to make a predetermined bending in a metallic plate originally plane.

<p>Process planning as a function for competitiveness is often neglected. However, as an intermediary between product development and manufacturing, it holds a key function in transforming product specifications and requirements into a producible process plan. Demands and requirements should be met concurrently as manufacturing costs and lead times are minimised. The focus of this thesis is the act of process planning, where the use of better methodologies, computer-aids and performance measurements are essential parts. Since process planning has the function of transforming demands and requirements, changing customer and regulative requirements are vital to regard. Since environmentally benign products and production increases in importance, the research presented in this thesis includes a CNC machining cost model, which relates machining costs to energy consumption.  The presented results in this thesis are based on quantitative and qualitative studies in the metal working industry.</p><p> </p><p>This thesis has contributed to an enhanced understanding of process planning to achieve better performance and important areas for improvements. Despite a 50 year history of computerised process planning aids, few of these are used in the industry, where manual process planning activities are more common. Process planning aids should be developed around the process planner so that non-value adding activities, such as information management and documentation are minimised in order to allow more resources for value adding activities, such as decision making. This thesis presents a study of systematic process planning in relation to perceived efficiency. This correlation could however not be verified, which opens up for further studies of other possible explanations for process planning efficiency. Process planning improvements in the industry are difficult to make, since there is little focus on process planning activities and limited knowledge about actual performance hereof. This means that measures taken regarding process planning development are difficult to verify.</p> / NFFP4

Process planning as a function for competitiveness is often neglected. However, as an intermediary between product development and manufacturing, it holds a key function in transforming product specifications and requirements into a producible process plan. Demands and requirements should be met concurrently as manufacturing costs and lead times are minimised. The focus of this thesis is the act of process planning, where the use of better methodologies, computer-aids and performance measurements are essential parts. Since process planning has the function of transforming demands and requirements, changing customer and regulative requirements are vital to regard. Since environmentally benign products and production increases in importance, the research presented in this thesis includes a CNC machining cost model, which relates machining costs to energy consumption.  The presented results in this thesis are based on quantitative and qualitative studies in the metal working industry.   This thesis has contributed to an enhanced understanding of process planning to achieve better performance and important areas for improvements. Despite a 50 year history of computerised process planning aids, few of these are used in the industry, where manual process planning activities are more common. Process planning aids should be developed around the process planner so that non-value adding activities, such as information management and documentation are minimised in order to allow more resources for value adding activities, such as decision making. This thesis presents a study of systematic process planning in relation to perceived efficiency. This correlation could however not be verified, which opens up for further studies of other possible explanations for process planning efficiency. Process planning improvements in the industry are difficult to make, since there is little focus on process planning activities and limited knowledge about actual performance hereof. This means that measures taken regarding process planning development are difficult to verify. / NFFP4

To facilitate the transition of Stereolithography (SLA) into the manufacturing domain and to increase its appeal to the micro manufacturing industry, process repeatability and surface finish need to be improved. Researchers have mostly focused on improving SLA surface finish within the capabilities of commercially available SLA machines. The capabilities of these machines are limited and a machine-specific approach for improving surface finish is based purely on empirical data. In order to improve surface finish of the SLA process, a more systematic approach that will incorporate process parameters is needed. To achieve this, the contribution of different laser and process parameters, such as laser beam angle, irradiance distribution, and scan speed, to SLA resolution and indirectly to surface finish, need to be quantified and incorporated into an analytical model. In response, a dynamic analytical SLA cure model has been developed. This model has been applied to SLA geometries of interest. Using flat surfaces, the efficacy of the model has been computationally and experimentally demonstrated. The model has been applied to process planning as a computational inverse design method by using parameter estimation techniques, where surface finish improvement on slanted surfaces has been achieved. The efficacy of this model and its improvement over the traditional cure models has been demonstrated computationally and experimentally. Based on the experimental results, use of the analytical model in process planning achieves an order of magnitude improvement in surface roughness average of SLA parts. The intellectual contributions of this research are the development of an analytical SLA cure model and the application of this model to process planning along with inverse design techniques for parameter estimation and subsequent surface finish improvement.

The process of taking a solid model and producing a machined part requires the time and skillset of a range of professionals, and several hours of part review, process planning, and production. Much of this time is spent creating a methodical step-by-step process plan for creating the part from stock. The work presented here is part of a software package that performs automated process planning for a solid model. This software is capable of not only greatly decreasing the planning time for part production, but also give valuable feedback about the part to the designer, as a time and cost associated with manufacturing the part. In order to generate these parameters, we must simulate all aspects of creating the part. Presented here are models that replicate these aspects. For milling, an automatic tool selection method is presented. Given this tooling, another model uses specific information about the part to generate a tool path length. A machining simulation model calculates relevant parameters, and estimates a time for machining given the tool and tool path determined previously. This time value, along with the machining parameters, is used to estimate the wear to the tooling used in the process. Using the machining time and the tool wear a cost for the process can be determined. Other models capture the time of non-machining production times, and all times are combined with billing rates of machines and operators to present an overall cost for machining a feature on a part. If several such features are required to create the part, these models are applied to each feature, until a complete process plan has been created. Further post processing of the process plan is required. Using a list of available machines, this work considers creating the part on all machines, or any combination of these machines. Candidates for creating the part on specific machines are generated and filtered based on time and cost to keep only the best candidates. These candidates can be returned to the user, who can evaluate, and choose, one candidate. Results are presented for several example parts. / text

Computer aided process planning (CAPP) is generally acknowledged as a significant activity to achieve Computer Integrated Manufacturing (CIM). In coping with the dynamic changes in the modern manufacturing environment, the awareness of developing integrated and intelligent CAPP systems has been raised in an attempt to generate more successful implementation of intelligent manufacturing systems. The main objective of this research work has been to develop an integrated intelligent process planning system that helps designers and process planners to improve their design and planning in the early stages of the product life cycle. In order to achieve this goal, the following specific objectives have been accomplished: (1) Developed a STEP-based feature modeler for building mechanical parts using high-level 3D solid features as the basic design entities. The modeler is capable of generating high-level product data in XML format according to ISO 10303-AP224 standard. This file can be used to integrate into CAPP/CAM systems without using a complex feature recognition process. (2) Developed a STEP-based intelligent process planning system for prismatic parts. The system maps STEP AP224 XML data file and produces the corresponding machining operations to generate a digital process plan in XML format according to ISO 14649 (STEP-NC) standard. A Hybrid approach of most recent techniques of artificial intelligence (neural networks, fuzzy logic and rule-based) is used as the inference engine of the developed system. Three neural network models are implemented to select machining operations, cutting tools, and machine tools. Several fuzzy logic models are utilized to select machining parameters for different machining operations, work material, and tool material combinations. The rule-based functions are utilized to perform operation sequence and setup planning. An object-oriented approach has been used in the definition and implementation of the developed system. This approach offers advantages of incremental system development and reusability. The developed system is integrated with AutoCAD using Activex automation interface. Several examples have been presented to demonstrate and verify the applicability of the developed system. Finally, this research will contribute significantly to the applicability of advanced artificial intelligent techniques in CAPP systems. The implementation of STEP technology in this research will support the integration of CAPP system with other systems in CIM environment. The developed system is intended to be an effective concurrent engineering tool that bridges the gap between design and manufacturing.

A previously developed feature library and algorithm are improved in order to develop a software capable of designing of parts to be manufactured using a four-axis CNC lathe. The developed program is composed of sections which are / part geometry design, process planning, cutting tool and machining parameter selection, part program generation and G-code simulation for verification. The developed program is capable of designing parts which contain axisymetric features for turning and related operations, and non-axisymetric features for milling on facial, lateral and cylindrical surfaces. Implemented design procedure defines a blank material shape that can be circular or polygonal cross-sectioned bar or a pre-manufactured part. A detailed database is created for proper cutting tool selection and machining data determination. User can either define or let the program to automatically select the cutting parameters like cutting speed, feed rate and depth of cut for each cutting tool with respect to the workpiece material being machined. After completing design and process planning procedures / information for generation of the CNC program becomes readily available for editing or transferring to the CNC machine tool. User can also simulate the NC program to verify the tool path. User friendly interface, which runs on Autodesk&#039 / s INVENTOR software to visualize the design process, allows design and modifications to be done very easily moreover previously designed parts can be redesigned to produce new modified parts.

Actuellement, les matériaux collectés à partir de produits en fin de vie sont recyclés en matière première pour être réutilisés dans un nouveau cycle de production. Cependant, la consommation énergétique des filières de recyclage reste importante. Le processus du recyclage fait aussi perdre la valeur ajoutée et l’énergie utilisée durant la fabrication de pièces originales. Aujourd’hui, les techniques de fabrication additive sont suffisamment performantes et permettent une fabrication de produits avec un matériau compatible avec l’usage. La prise en compte des performances de ces nouvelles techniques dans une stratégie soutenable peut ouvrir des pistes pour modifier les pièces et les réutiliser directement sans retourner au niveau de matière première. Cette thèse a pour objectif de développer une stratégie soutenable, qui permet de donner une nouvelle vie à une pièce en fin de vie (ou une pièce existante) en la transformant directement en une nouvelle pièce destinée à un autre produit. Afin de développer une telle stratégie, les travaux menés de la thèse visent à résoudre les verrous scientifiques suivants :Le premier verrou scientifique est lié à la faisabilité technologique : est-il possible de déposer de la matière sur une pièce existante en utilisant les techniques de fabrication additive pour obtenir la nouvelle pièce avec une bonne santé de matière ? Cette question a été résolue en réalisant une étude expérimentale sur l’observation de microstructures et de propriétés mécaniques des éprouvettes, qui sont fabriquées par ajout de nouvelles entités sur une pièce existante en EBM. Le deuxième verrou scientifique est lié à l’étude de la chaîne complète de fabrication d’un point de vue technologique. Comment concevoir des gammes de fabrication en combinant intelligemment des opérations additives et soustractives pour obtenir la pièce attendue à partir de la pièce existante ? Une méthode de conception des gammes de fabrication combinant les procédés additifs et soustractifs a été proposée en s’appuyant sur le concept d’entités de fabrication additive et soustractive. Le troisième verrou scientifique est lié à la soutenabilité et la stratégie présente-t-elle des avantages par rapport à la stratégie conventionnelle en termes de soutenabilité ? Une approche s’appuyant sur la méthode d’Analyse du Cycle de Vie (ACV) a aussi été développée pour évaluer des impacts environnementaux. Des critères permettant de qualifier le domaine de la stratégie proposée vis-à-vis de la stratégie conventionnelle ont été identifiés / Currently, materials collected from end-of-life (EoL) products are recycled into raw material for reusing in a new production cycle. However, energy consumptions of recycling sectors remain important. The added values and energy used in the manufacture of original parts are also lost during the material recycling process. Nowadays, additive manufacturing techniques are sufficiently efficient and allow the manufacture of products with a material compatible with the use. Taking into account the performances of these techniques in a sustainable strategy can open the ways to modify parts and reuse them directly without returning to the raw material level. This thesis aims to develop a sustainable strategy, which allows giving a new life to an EoL part (or an existing part) by transforming it directly into a new part intended for another product. In order to develop such a strategy, the works of the thesis aims to solve the following scientific issues : the first scientific issue is related to the technological feasibility : is it possible to deposit material on an existing part using additive manufacturing technologies to obtain the new part with good material health ? This question is solved by carrying out an experimental study on the observation of microstructures and mechanical properties of the samples, which are manufactured by adding new features into an existing part in EBM. The second scientific issue is related to the study of the complete manufacturing chain from a technological point of view. How to design the process planning for additive and subtractive manufacturing combination to manufacture the expected part from the existing part ? To solve this question, a methodology to design the process planning for combining these manufacturing processes has been proposed based on the concept of additive manufacturing and machining features.The third scientific issue is linked to the sustainability and does the new strategy have advantages in comparison to the conventional strategy in terms of sustainability ? An approach based on the Life Cycle Assessment (LCA) method has also been developed to assess environmental impacts. The criteria for qualifying the domain of the proposed strategy vis-a-vis the conventional strategy were also identified

Submitted by June Marques Fernandes (june.marques@gmail.com) on 2018-01-11T14:24:34Z No. of bitstreams: 1 05-Tese Doutorado June Marques Fernandes-11jan2018.pdf: 5912972 bytes, checksum: f1f62a045568184533b4f304b9275ee6 (MD5) / Approved for entry into archive by Maria Tereza Fernandes Conselmo (maria.conselmo@fgv.br) on 2018-01-11T17:15:12Z (GMT) No. of bitstreams: 1 05-Tese Doutorado June Marques Fernandes-11jan2018.pdf: 5912972 bytes, checksum: f1f62a045568184533b4f304b9275ee6 (MD5) / Made available in DSpace on 2018-01-11T17:25:57Z (GMT). No. of bitstreams: 1 05-Tese Doutorado June Marques Fernandes-11jan2018.pdf: 5912972 bytes, checksum: f1f62a045568184533b4f304b9275ee6 (MD5) Previous issue date: 2017-12-12 / As universidades e os centros de pesquisa passaram a desempenhar o papel de capitalizar o conhecimento, propiciando a geração de riqueza e o desenvolvimento social, caracterizando-se como universidades empreendedoras. Contudo, para promover a inovação tecnológica no ambiente acadêmico, observa-se a importância de estruturar um processo de planejamento de negócios tecnológicos (PPNT) que consiga contemplar aspectos sobre produto, tecnologia, transferência de tecnologia e negócios. Dessa forma como parte das contribuições deste estudo, foi realizada aintegração de três processos para consubstaciação do PPNT, são eles: i) o Processo de Planejamento Tecnológico (PPTec), que busca auxiliar na incorporação da tecnologia ao produto e na aproximação deste em relação ao mercado; ii) o Processo de Planejamento de Transferência de Tecnologia (PPTT), que consiste em uma estruturação das fases que compõem o processo de transferência de tecnologia das Universidades para o mercado; e iii) o Processo de Planejamento de Negócios (PPNeg), que corresponde às fases de desenvolvimento do negócio. Observa-se que esses processos de auxílio à gestão da inovação ainda estão envoltos em desperdícios que afetam sua efetiva operacionalização. Em termos práticos isso implica assumir maiores custos para a entrega de tecnologias e negócios ao mercado. Esse aspecto nos conduz a uma reflexão sobre a necessidade da adoção de métodos e ferramentas (denominaremos de “práticas”) orientados pelos princípios lean, em especial para o Lean Product Development (LPD) e o Lean Startup Methodology (LSM). Para responder ao problema de pesquisa proposto – qual seja, “Como as práticas do LPD e LSM contribuem para o PPNT no ambiente acadêmico?” –, foram definidos dois objetivos gerais de pesquisa: a) identificar um conjunto de práticas do LPD que contribuem para a operacionalização do PPTec; b) identificar e avaliar as contribuições das práticas LSM às fases do PPTec, do PPNeg e do PPTT. Para proceder à investigação, esta tese está organizada em quatro capítulos: (i) no capítulo 1, utilizando a pesquisa-ação, objetivou-se a caracterização do modelo de negócios de cada projeto tecnológico analisado; (ii) no capítulo 2, por meio do estudo de casos múltiplos, foi obtida a frequência com que os pesquisadores-empreendedores vivenciaram as categorias e subcategorias de desperdícios durante o desenvolvimento do PPNT, sob a perspectiva do LPD; (iii) no capítulo 3, com a revisão de literatura, foi possível identificar as práticas relacionadas ao LPD capazes de contribuir com a redução dos desperdícios vivenciados pelas equipes dos projetos em diferentes fases do PPTec; (iv) o capítulo 4, por meio da revisão de literatura e, posteriormente, da pesquisa ação, teve o objetivo de identificar e avaliar as práticas LSM capazes de contribuir para mitigar os desperdícios vivenciados pelas equipes dos projetos nas diferentes fases do PPTT e PPNeg. Como resultado da pesquisa, tem-se: 1) a caracterização do modelo de negócio dos casos analisados e a validação empírica do modelo proposto por Reis, Ladeira e Fernandes (2015); 2) uma contribuição ao arcabouço teórico sobre o LPD, na medida em que foi possível identificar as práticas LPD capazes de contribuir com a operacionalização do PPTec em suas diferentes fases, sob uma perspectiva teórica; e 3) uma contribuição ao arcabouço teórico sobre o LSM, uma vez que foram identificadas as práticas LSM capazes de contribuir na operacionalização do PPTec, PPTT e PPNeg, sob uma perspectiva prática. Como limitação da pesquisa, destaca-se que não foram confrontadas as práticas e desperdícios na etapa de ideação da tecnologia. Outra limitação reside no fato da pesquisa ter sido aplicada em somente nove projetos de base tecnológica no ambiente acadêmico. Assim, entende-se importante a ampliação do estudo para spinoffs de outros contextos (corporativos ou públicos). A pesquisa pôde contribuir com o enriquecimento e a ampliação da literatura sobre LPD, LSM e PPNT, além de auxílio ao processo de inovação tecnológica na universidade. / Universities and research centers began to play the role of capitalizing knowledge, fostering wealth generation and social development, characterizing themselves as entrepreneurial universities. However, to promote technological innovation in the academic environment, it is important to structure a Technological Business Planning Process (TBPP), whose composition is based on three pillars: (i) Technological Planning Process (TPP), that seeks to aid the incorporation of technology, (ii) the Technology Transfer Planning Process (TTPP), consisting of a structuring of all the phases that make up the process of transferring technology from universities to the market, and (iii) the Business Planning Process (BPP), that corresponds to the phases of business development. Together, these three processes comprise the Technological Business Planning Process (TBPP). The structuring of the processes of these businesses is immersed in several situations involving losses and wastes (for example: excessive waiting time, delay and rework during the development process, among others). This aspect leads us to a reflection on the need to adopt methods and tools (we will call this research as practices), guided by lean principles, especially for Lean Product Development (LPD) and Lean Startup Methodology (LSM). In order to respond to the proposed research problem, namely: “How do LPD and LSM practices contribute to PPNT in the academic environment?”, two general research objectives were defined: a) identify a set of LPD practices that contribute to the operation of the PPTec; b) to evaluate the contributions of LSM practices to the TPP, BPP and TTPP phases. In order to proceed with the research, this thesis was organized into four chapters with objectives and different methodological strategies: i) in chapter 1 using the methodological action research strategy was aimed at characterizing the business model of each technological project analyzed; ii) in chapter 2, through the multi-case study, the frequency with which the entrepreneur-researchers had experienced the waste categories and subcategories during the development of the three processes that integrate the TBPP, using the perspective of the LPD; iii) in chapter 3, based on the literature review, it was possible to identify LPD-related practices that can contribute to the reduction of waste experienced by project teams in different phases of the TPP process; iv) chapter 4, through literature review and later action research, had the objective of identifying the LSM practices that could contribute to mitigate the waste experienced by project teams in the different phases of TTPP and BPP. As a result of the research we have: 1) improvement and empirical validation of the model proposed by Reis, Ladeira and Fernandes (2015); 2) contribution to the theoretical framework on LPD, since it was possible to identify LPD practices capable of contributing to the operation of the TPP in its different phases; 3) contribution to the theoretical framework on LSM, since the LSM practices were able to contribute to the operationalization of TTPP and BPP, from a theoretical perspective. As a limitation of the research, we have not been confronted with the practices and wastes in the stage of ideation of the technology, in order to identify the contributions of the same to the initial stages of the business. In part this limitation was related to the specificities of the analyzed projects, since all had a version of its technological product. Another limitation is that the research was applied in only 9 technology-based projects in the academic environment. From this aspect it is important to expand the studies for spinoffs of corporate contexts or belonging to other programs and initiatives to encourage innovation. For the time being, this research was able to contribute to the enrichment and expansion of the literature on LPD, LSM and TBPP, as well as to present mechanisms to aid the process of technological innovation in the academic environment, and to have guided the development of the cases studied.

Orientador: Antônio Carlos Moretti / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-17T07:59:31Z (GMT). No. of bitstreams: 1 Pinto_LuisFrancodeCampos_M.pdf: 11074962 bytes, checksum: 1a81559fbea90f37c92a435180da70b3 (MD5) Previous issue date: 2010 / Resumo: Neste trabalho, foi desenvolvida uma aplicação prática de técnicas da pesquisa operacional para a resolução de um problema real de esquematização ou programação de máquinas. Este problema deriva de um flexible job shop scheduling, porém apresentando diversas características próprias, impossibilitando a aplicação de modelos disponíveis na literatura. O desempenho da utilização da combinação de um modelo de programação linear inteira mista com uma heurística de construção e uma heurística de melhoramento foi avaliado diante de cenários reais obtidos da indústria de produção de frascos plásticos. Estas técnicas provaram ser eficientes para a resolução dos casos propostos / Abstract: In this work, a practical application of operational research techniques was developed to solve a real machine scheduling or programming problem. This problem derives from a flexible job shop scheduling framework, but presents several unique characteristics, which makes it impossible to apply models available in literature. The performance of using a combination of a mixed integer programming model with a construction heuristic and a improvement heuristic was evaluated using real world scenarios obtained from the plastic bottle production industry. Theses techniques were proven efficient in resolving the proposed cases / Mestrado / Pesquisa Operacional / Mestre em Matemática Aplicada