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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.
151

Computer-Aided Manufacturing Planning (CAMP)of Mass Customization for Non-rotational Part Production

Yao, Suqin 16 December 2003 (has links)
"This research is aimed at studying the key technologies of Computer-Aided Manufacturing Planning (CAMP) of mass customization for non-rotational part production. The main goal of the CAMP is to rapidly generate manufacturing plans by using of the best-of-practice (BOP) provided by specific companies. A systematic information modeling hierarchy is proposed to facilitate changes in manufacturing plans according to changes in part design. The Object-oriented Systems Analysis (OSA) approach is used to represent information relationships and associativities in the CAMP. A feature-based part information model, a process model, a setup planning model, and manufacturing resource capability models are established. A three-level decision-making mechanism is proposed for the CAMP. At the feature- level, combined features are defined based on part families, and a process model is proposed to describe the information associativities between features and their manufacturing strategies, which include customized cutters and toolpaths. At the part level, graph-based setup planning is carried out by tolerance analysis and manufacturing resource capability analysis. At the machine level, multi-part fixtures are utilized to pursue high productivity. Cycle time is used to evaluate manufacturing plans. Computer software for the CAMP has been developed and integrated with CAD package Unigraphs. The BOP of part families is stored in XML format, which has good extendibility and can be read and edited by standard browsers."
152

Método de desenvolvimento de órtese personalizada de baixo custo para a manufatura aditiva / Method for low-cost custom orthosis development aiming additive manufacturing

Weigert, Mateus Collares 31 July 2017 (has links)
CAPES; CNPq / O emprego da Manufatura Aditiva (AM) vem aperfeiçoando a confecção de produtos assistivos customizados, mas para a sua utilização se faz necessário gerar o modelo geométrico digital. Uma das alternativas para obtê-lo é com o uso de escâneres 3D. Após a digitalização, dificilmente o resultado alcançado, geralmente uma malha digital da superfície 3D do modelo físico, pode ser utilizado diretamente na AM. Para tanto, é exigido alguns tratamentos desta tmalha em programas CAD (Computer-Aided Design) 3D. Algumas dessas ferramentas, tanto os escâneres 3D quanto os programas CAD 3D, são viáveis, mas de alto custo. Além disso, a etapa de tratamento da malha não é abordada nos estudos encontrados, prejudicando a disseminação dessas tecnologias. Desta forma, o presente trabalho propõe um método de baixo custo para o desenvolvimento de órtese de membro superior visando a fabricação por AM, tendo como foco principal a abordagem das etapas de tratamento da malha e modelagem da órtese. Como objeto de estudo foram utilizados 12 moldes em gesso de punho, mão e dedos confeccionados por um terapeuta ocupacional. A digitalização dos moldes em gesso ocorreu com o emprego de dois sistemas de baixo custo, o sensor do Kinect 360 e o programa Remake, e um de alto custo para servir como referência, o escâner REVscan. Para as etapas de tratamento da malha e modelagem da órtese foram utilizados dois programas CAD 3D gratuitos: Blender e Meshmixer. Os digitalizadores de baixo custo geraram malhas que foram validadas ao compará-las as geradas pelo REVscan. Diferentemente do Remake, o Kinect gerou malhas sem defeitos e em menor tempo, porém, apresentou os maiores desvios dimensionais e os maiores tamanhos de arquivo. Os defeitos apresentados nas malhas geradas pelo Remake foram do tipo lacunas e foram corrigidos com êxito pelos programas CAD 3D. Na etapa de tratamento da malha foi constatada a relevância da etapa de suavização das bordas no resultado final da órtese. Os resultados ressaltaram a importância da etapa de tratamento e correção das malhas para o desenvolvimento de produtos assistivos visando a fabricação por AM. De forma geral, foi possível desenvolver órteses personalizadas utilizando as ferramentas de baixo custo. Os procedimentos descritos neste estudo podem auxiliar no desenvolvimento de produtos assistivos e propiciar a disseminação desse conhecimento nas empresas e instituições dispensadoras de órteses. / The use of the Additive Manufacturing (AM) has improved the production of customized assistive products, but its use needs to generate the digital geometric model first. One of the alternatives to get it is with the use of 3D scanners. After the scanning, hardly the result achieved, usually a digital STL (stereolithography format) mesh of the 3D surface of the physical model, can be used directly in AM. Therefore, it is required some mesh treatments in 3D CAD (Computer-Aided Design) programs. Some of these tools, both 3D scanners and 3D CAD programs, are feasible but high cost. In addition, the mesh treatment step is not addressed in the studies found, hampering the spread of these technologies. In this way, the present work proposes a low cost method for the development of upper limb orthosis aimed at manufacturing by AM, focusing mainly on the steps of mesh treatment and orthosis modeling. As object of study were used 12 gypsum molds of wrist, hand and fingers made by an occupational therapist. The 3D digitizing of plaster casts occurred using two low-cost systems, the Kinect 360 sensor and the Remake program, and a high-cost scanner to serve as a reference, the REVscan. For the steps of mesh treatment and orthoses modeling, two free 3D CAD programs were used: Blender and Meshmixer. The lowcost scanners generated meshes that were validated by comparing them to those generated by REVscan. Unlike Remake, Kinect generated non-defective meshes and in less time, however, presented the largest dimensional deviations and the largest file sizes. The defects presented in the meshes generated by Remake were of the gaps type and were corrected successfully by 3D CAD programs. In the mesh treatment step, it was verified the relevance of the procedure of smoothing the edges in the final orthosis result. The results highlighted the importance of the meshes treating step for the development of assistive products aiming the manufacture by AM. In general, it was possible to develop customized orthoses using low-cost tools. The procedures described in this study can assist in the development of assistive products and facilitate the dissemination of this knowledge in companies and institutions that provide orthosis.
153

Interactive Design Interfaces to support Ideation & Rapid Prototyping

Devashri Utpal Vagholkar (11816888) 19 December 2021 (has links)
Generating ideas and creating prototypes of physical products is a highly non-linear and iterative process. Current tools divide this process into multiple discrete steps with different tools to support each of these steps such as CAD modelling, simulation and fabrication. We believe, design interfaces that combine different steps of the process and create different layers of abstraction depending on the type of the user and where they are in the process can support users in generating more creative ideas and creating better functioning prototypes more efficiently. In order to validate this, we developed three interfaces- a sketch-based ideation tool, a live programming interface to create IoT devices and a design tool to support design and fabrication of hand wearables. The foundation of these design interfaces is the layer of abstraction that allows users to focus on idea generation and converting it into a tangible prototype with little or no technical knowledge, and a continuous visual feedback that guides the user to make necessary changes to improve their design. The three tools were evaluated through user testing for supporting creation of different ideas and converting them into functional prototypes.
154

Uso do software CAM em auxílio a estimativa de custos de fabricação na fase inicial do desenvolvimento de produtos poliméricos injetados

Holzmann, Henrique Ajuz 30 May 2014 (has links)
Capes / No contexto atual do setor industrial onde a competitividade é cada vez maior, reduzir as incertezas presentes durante o desenvolvimento de novos produtos se torna essencial. Para isso podem ser utilizados os modelos de referência do PDP (Processo de Desenvolvimento do Produto), os quais visam uma melhoria de projeto, facilitando seu desenvolvimento e reduzindo as incertezas. Alguns segmentos industriais exigem grandes investimentos iniciais para a produção do produto, podendo-se destacar o de injeção polimérica. Neste processo há uma aquisição inicial do molde de injeção, o qual é responsável por grande parcela dos custos finais do produto, sendo este indispensável à realização da etapa. Visto isso, a utilização de ferramentas que propiciem uma redução de incertezas torna-se de grande valia. Uma destas ferramentas é o software CAM, que rotineiramente é utilizado nas fases do projeto detalhado e preparação da produção. Utilizá-lo de maneira não tradicional, em auxílio a estimativa de custos, já nas fases iniciais do PDP pode trazer algumas vantagens ao desenvolvimento do projeto. Com isso busca-se identificar a contribuição do software CAM como ferramenta de auxílio na estimativa de custos para tomada de decisão na fase inicial do processo de desenvolvimento de produtos poliméricos injetados. Para a realização do trabalho, buscou-se avaliar as fases iniciais dos modelos de referência do PDP a fim de identificar as atividades dadas como essenciais ao processo. Com a identificação das fases, foram correlacionadas quais funcionalidades do software CAM auxiliam na realização das atividades na fase inicial do PDP. Com isso propôs-se uma metodologia para estimar os custos de fabricação do molde de injeção para a fase inicial do PDP. Realizou-se então um estudo de caso, variando-se o design do produto, no qual buscou-se identificar a contribuição do software CAM na estimativa dos custos de fabricação. Após a realização do estudo de caso, percebe-se que a ferramenta CAM pode auxiliar na fase inicial do projeto, pois a mesma favorece a seleção do design do produto a ser fabricado, visto que pode-se através do software CAM estimar os tempos e as ferramentas de usinagem necessárias à fabricação do molde de injeção. Nota-se ainda que esta ferramenta favorece a definição do portfólio de produtos através da estimativa dos custos para fabricação do molde. / In the current context of the industrial sector where competitiveness is increasing, reducing the uncertainties present during the development of new products becomes essential. For this reference model of the PDP, which aim to improve the design, facilitating their development and reducing uncertainty can be used. Some industries require large initial investment for the production of the product and may highlight the polymer injection. In this process, there is an initial purchase of injection mold, which is responsible for a large portion of the final cost of the product, which is essential to carry out the step. Seen that the use of tools that may reduce the uncertainties become very valuable. One of these tools is the CAM software, which is routinely used in the stages of detailed design and production preparation. Use it for non-traditional way, aid in the cost estimate, since in the early stages of the PDP can bring some advantages to the project development. Thus, we seek to identify the contribution of CAM software tool to aid in estimating costs for decision-making early in the development process injected polymer products. To conduct the study sought to evaluate the early stages of the reference models of the PDP in order to identify activities as essential given the process. With the identification of the phases of CAM, software features, which assist in performing the activities in the initial phase of the PDP, were correlated. With this proposed a methodology for estimating the costs of manufacturing injection mold for the initial phase of the PDP. Then performed a case study, varying the design of the product, in which we attempted to identify the contribution of CAM software in estimates of manufacturing costs. After the completion of the case study, it can be seen that the CAM tool can assist in the initial design stage, because it favors the selection of the design of the product being manufactured, as it can be through the CAM software to estimate the times and machining tools needed to manufacture the injection mold. Note also that this tool favors the definition of the product portfolio by estimating costs for mold manufacturing.
155

Uso do software CAM em auxílio a estimativa de custos de fabricação na fase inicial do desenvolvimento de produtos poliméricos injetados

Holzmann, Henrique Ajuz 30 May 2014 (has links)
Capes / No contexto atual do setor industrial onde a competitividade é cada vez maior, reduzir as incertezas presentes durante o desenvolvimento de novos produtos se torna essencial. Para isso podem ser utilizados os modelos de referência do PDP (Processo de Desenvolvimento do Produto), os quais visam uma melhoria de projeto, facilitando seu desenvolvimento e reduzindo as incertezas. Alguns segmentos industriais exigem grandes investimentos iniciais para a produção do produto, podendo-se destacar o de injeção polimérica. Neste processo há uma aquisição inicial do molde de injeção, o qual é responsável por grande parcela dos custos finais do produto, sendo este indispensável à realização da etapa. Visto isso, a utilização de ferramentas que propiciem uma redução de incertezas torna-se de grande valia. Uma destas ferramentas é o software CAM, que rotineiramente é utilizado nas fases do projeto detalhado e preparação da produção. Utilizá-lo de maneira não tradicional, em auxílio a estimativa de custos, já nas fases iniciais do PDP pode trazer algumas vantagens ao desenvolvimento do projeto. Com isso busca-se identificar a contribuição do software CAM como ferramenta de auxílio na estimativa de custos para tomada de decisão na fase inicial do processo de desenvolvimento de produtos poliméricos injetados. Para a realização do trabalho, buscou-se avaliar as fases iniciais dos modelos de referência do PDP a fim de identificar as atividades dadas como essenciais ao processo. Com a identificação das fases, foram correlacionadas quais funcionalidades do software CAM auxiliam na realização das atividades na fase inicial do PDP. Com isso propôs-se uma metodologia para estimar os custos de fabricação do molde de injeção para a fase inicial do PDP. Realizou-se então um estudo de caso, variando-se o design do produto, no qual buscou-se identificar a contribuição do software CAM na estimativa dos custos de fabricação. Após a realização do estudo de caso, percebe-se que a ferramenta CAM pode auxiliar na fase inicial do projeto, pois a mesma favorece a seleção do design do produto a ser fabricado, visto que pode-se através do software CAM estimar os tempos e as ferramentas de usinagem necessárias à fabricação do molde de injeção. Nota-se ainda que esta ferramenta favorece a definição do portfólio de produtos através da estimativa dos custos para fabricação do molde. / In the current context of the industrial sector where competitiveness is increasing, reducing the uncertainties present during the development of new products becomes essential. For this reference model of the PDP, which aim to improve the design, facilitating their development and reducing uncertainty can be used. Some industries require large initial investment for the production of the product and may highlight the polymer injection. In this process, there is an initial purchase of injection mold, which is responsible for a large portion of the final cost of the product, which is essential to carry out the step. Seen that the use of tools that may reduce the uncertainties become very valuable. One of these tools is the CAM software, which is routinely used in the stages of detailed design and production preparation. Use it for non-traditional way, aid in the cost estimate, since in the early stages of the PDP can bring some advantages to the project development. Thus, we seek to identify the contribution of CAM software tool to aid in estimating costs for decision-making early in the development process injected polymer products. To conduct the study sought to evaluate the early stages of the reference models of the PDP in order to identify activities as essential given the process. With the identification of the phases of CAM, software features, which assist in performing the activities in the initial phase of the PDP, were correlated. With this proposed a methodology for estimating the costs of manufacturing injection mold for the initial phase of the PDP. Then performed a case study, varying the design of the product, in which we attempted to identify the contribution of CAM software in estimates of manufacturing costs. After the completion of the case study, it can be seen that the CAM tool can assist in the initial design stage, because it favors the selection of the design of the product being manufactured, as it can be through the CAM software to estimate the times and machining tools needed to manufacture the injection mold. Note also that this tool favors the definition of the product portfolio by estimating costs for mold manufacturing.
156

The Study of Behavior of Passenger Car-Semi-Autonomous Trailer Connections under Load

Yury Kuleshov (11187051) 27 July 2021 (has links)
<div><p>A variety of passenger car-trailer connections exist on the market. One specific type of the connections provides a tensile force measurement capability for the purpose of providing feedback for the semi-autonomous trailer’s control system. Semi-autonomous trailer is an innovative technology that can encourage drivers to use smaller vehicles for towing, which will contribute to restoration and improvement of urban infrastructure (NAE Grand Challenges for Engineering, 2020). The vehicle-semi-autonomous trailer connection’s safety concerns depend on multiple factors, but start with either a mechanical, or an electrical failure. The topic of safety of passenger car-semi-autonomous trailer connections is not well present in literature. The connections’ mechanical failures under load are in the focus of this work. The author addressed the following research question and the sub question. How do the existing “passenger car-trailer” connections with tensile force measurement capability compare to one another under load in terms of the possible failure? What is the failure mode of each of the compared connections? The author selected three prototypes from the literature, built three-dimensional (3D) models in SolidWorks 2018 and simulated the tests in the program’s add-on in accordance with the requirements of an industry standard on real-life testing of specific vehicle systems. The author compared the three prototypes by a number of different parameters. The research showed that none of the three existing prototypes are public road-ready in terms of safety. The study can be useful for future designers of passenger-car-semi-autonomous trailer connections.</p></div>
157

PRODUCT-APPLICATION FIT, CONCEPTUALIZATION, AND DESIGN OF TECHNOLOGIES: PROSTHETIC HAND TO MULTI-CORE VAPOR CHAMBERS

Soumya Bandyopadhyay (13171827) 29 July 2022 (has links)
<p>From idea generation to conceptualization and development of products and technologies is a non-linear and iterative process. The work in this thesis follows a process that initiates with the review of existing technologies and products, examining their unique value proposition in the context of the specific applications for which they are designed. Next, the unmet needs of novel or emerging applications are identified that require new product or technologies. Once these user needs and product requirements are identified, the specific functions to be addressed by the product are specified. The subsequent process of design of products and technologies to meet these functions is enabled by engineering tools such as three-dimensional modelling, physics-based simulations, and manufacturing of a minimum viable prototype. In these steps, un-biased decisions have to be taken using weighted decision matrices to cater to the design requirements. Finally, the minimum viable prototype is tested to demonstrate the principal functionalities. The results obtained from the testing process identify the potential future improvements in the next generations of the prototype that would subsequently inform the final design of product. This thesis adopted this methodology to initiate the design two product-prototypes: i) an image-recognition-integrated service (IRIS) robotic hand for children and ii) cascaded multi-core vapor chamber (CMVC) for improving performance of next-generation computing systems. Minimum viable product-prototypes were manufactured to demonstrate the principal functionalities, followed by clear identification of future potential improvements. Tests of the prosthetic hand indicate that the image-recognition based feedback can successfully drive the actuators to perform the intended grasping motions. Experimental testing with the multi-core vapor chamber demonstrates successful performance of the prototype, which offers notable reduction in temperatures relative to the existing benchmark solid copper spreader. </p>
158

The Biowall Field Test Analysis and Optimization

Jacob J. Torres (5930906) 14 May 2019 (has links)
<div> <p>A residential botanical air filtration system (Biowall) to investigate the potential for using phytoremediation to remove contaminants from indoor air was developed. A full scale and functioning prototype was installed in a residence located in West Lafayette, Indiana. The prototype was integrated into the central Heating, Ventilating, and Air Conditioning (HVAC) system of the home. This research evaluated the Biowall operation to further its potential as an energy efficient and sustainable residential air filtration system.<br></p> <p> </p> <p>The main research effort began after the Biowall was installed in the residence. A field evaluation, which involved a series of measurements and data analysis, was conducted to identify treatments to improve Biowall performance. The study was conducted for approximately one year (Spring 2017-Spring 2018). Based on the initial data set, prioritization of systems in need of improvement was identified and changes were imposed. Following a post-treatment testing period, a comparison between the initial and final performances was completed with conclusions based on this comparison. </p> <p> </p> <p>The engineering and analysis reported in this document focus on the air flow path through the Biowall, plant growth, and the irrigation system. The conclusions provide an extensive evaluation of the design, operation, and function of the Biowall subsystems under review.</p> </div> <br>

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