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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.
91

Potencializando a experiência da criança de educação infantil através da interface gráfica no ambiente TVDi

Demarchi, Gustavo Scussel January 2015 (has links)
A presente pesquisa pretende demonstrar como o design, por meio do conhecimento das características cognitivas e psicológicas de crianças de educação infantil (idade entre quatro e cinco anos, de acordo com o MEC), frente às possibilidades tecnológicas do ambiente da TV Digital Interativa (TVDi) pode gerar diretrizes projetuais que permitam o desenvolvimento de aplicativos e que venham a auxiliar a construção de experiências mais ativas a esses usuários. Supõe-se que através da criação e sincronização desses elementos, se pode proporcionar o desenvolvimento de interfaces gráficas amigáveis (IGA´s) mais eficientes na construção do conhecimento. A pesquisa advém da necessidade de projetar aplicativos que utilizem de forma mais eficaz as possibilidades interativas, bem como contribuir com iniciativas que permitam o uso da TVDi como ferramenta de inclusão tecnológica e social. Esse cenário de pesquisa apresenta-se propício ao se verificar a abrangência da TV nos lares brasileiros, bem como a conversão definitiva do sinal analógico para digital, que ocorrerá até o ano de 2018. A investigação teórica relata os impactos na relação entre a criança e televisão a partir de estudos conduzidos ao longo dos anos, e busca entender como a informação é percebida por usuários nessa faixa etária, bem como estabelecer a abordagem narrativa mais adequada a esse usuário. Essa fase gerou diretrizes que embasaram o instrumento de coleta de dados por meio da pesquisa de campo, conduzidas a partir de entrevistas com especialistas das áreas de psicopedagogia, narrativa e design. A interpretação dos dados através do confronto proveniente da pesquisa teórica e prática dessas áreas do conhecimento geraram diretrizes de projeto de interface que tiveram a comprovação de sua eficácia em sua aplicabilidade por meio da avaliação em atividade de grupo focal, formado por especialistas da área do design. Essa etapa final da pesquisa resultou em um conjunto de diretrizes capazes de auxiliar desenvolvedores e projetistas a potencializarem a experiência da criança em educação infantil através da interatividade nos ambientes digitais. Finaliza-se com conclusões e contribuições e sugestões para futuros estudos. / This research aims to demonstrate how the design, through the knowledge of cognitive and psychological characteristics of childhood education (ages four and five, according to the Brazil’s Ministry of Education), toward to the environment of the technological capabilities of the Interactive Digital TV (iDTV), can generate projective guidelines that enable the development of applications which will help to build more active experiences for those users. It is assumed that through the creation and synchronization of these, it can provide the development of friendly graphical user interfaces (IGA's) more efficient in the construction of knowledge. The research comes from the need to design applications that use more effectively the interactive possibilities and contribute to effort to enable the use of iDTV as technological and social inclusion tool. This scenario research presents conducive to verify the scope of TV in Brazilian homes, and the final conversion of the analog signal to digital, which will occur by the year 2018. The theoretical research reports the impacts on the relationship between the child and television from studies conducted over the years, and seeks to understand how information is perceived by users in this age group and also to establish the most appropriate narrative approach to this user. This phase generated guidelines which supported the data collection instrument through field research, conducted through interviews with experts in educational psychology, narrative and design areas. Interpretation of the data through the coming confrontation of theoretical and practical research of these areas of knowledge generated interface design guidelines that had the evidence of its effectiveness in its applicability through the evaluation focus group activity, comprising the area of design experts. This final stage of the study resulted in a set of guidelines that can assist developers and designers potentiating the child's experience in early childhood education through interactivity in digital environments. The research ends with conclusions, contributions and suggestions for future studies.
92

[en] 3D TECHNOLOGIES EXPERIMENTATION BY STUDENTS IN THE KINDERGARTEN IN THE CITY OF RIO DE JANEIRO / [pt] EXPERIMENTAÇÃO DE TECNOLOGIAS 3D POR ALUNOS DO ÚLTIMO ANO DA EDUCAÇÃO INFANTIL NA CIDADE DO RIO DE JANEIRO

MARIO RICARDO DA SILVA LIMA 26 July 2017 (has links)
[pt] As tecnologias 3D estão se consolidando em espaços profissionais e, entre suas possibilidades de uso, está seu emprego no contexto educacional. As pesquisas para desenvolvimento de tecnologias partem de um referencial ainda distante da realidade educacional e com predominância de visões advindas do público adulto. Nesse sentido, há espaço para o entendimento de como as crianças experimentam tais tecnologias - impressão 3D (manufatura aditiva), modelagem 3D e escaneamento 3D - no ambiente escolar da Educação Infantil. A presente pesquisa busca investigar qual a contribuição da experimentação das tecnologias 3D para a Educação Infantil, objetivando abrir possibilidades para o entendimento das formas de experimentação pelos alunos. A partir da leitura de documentos governamentais e de teóricos da educação e do desenvolvimento infantil, além do levantamento de outras experiências semelhantes, foi estruturado um experimento composto por três encontros, baseados no método de pesquisa-ação. O primeiro encontro ocorreu no espaço não formal do museu - para apresentação das tecnologias - e os outros dois no ambiente de sala de aula - para a experimentação e reflexão sobre as tecnologias. Para o experimento, foram selecionadas três turmas do último ano da Educação Infantil da escola Curiosa Idade, além do Museu Internacional de Arte Naif. Para a análise dos dados obtidos, foi utilizada a abordagem da Sociolinguística Interacional. Foi constatado que os alunos do último ano da Educação Infantil são capazes de compreender todo o processo, do escaneamento 3D de objetos, passando pela customização via modelagem 3D e chegando ao objeto modificado impresso em 3D. Além disso, verificou-se que a ludicidade e a criatividade são potencializadas pelo uso das tecnologias 3D. / [en] The 3D technologies are ever more present in professional spaces, and among their possibilities is their employment in the educational context. The research for technologies development starts from a referential still far from the educational reality and with visions coming predominatly from the perspective of adults. In this sense, there is room for understanding how children experience such technologies - 3D printing (additive manufacturing), 3D modeling and 3D scanning - in the preschool environment of Educação Infantil (brazilian stage similar to the Early Childhood Education). The present research seeks to investigate the contribution of the 3D technologies experimentation to Educação Infantil, aiming to open possibilities for the understanding of the ways of experimentation by the students. Having reviewed governmental documents and education and child development theorists, besides surveying similar experiences, an experiment was structured consisting of three meetings, based on the action-research method. The first meeting took place in the museum s non-formal space - for the presentation of technologies - and the other two in the classroom environment - for experimentation and reflection on technologies. For the experiment, three groups attending the kindergarten at the Curiosa Idade school, as well as the International Museum of Naif Art, were selected. For the analysis of the obtained data, the approach of Interactional Sociolinguistics was applied. It was found that the students of the kindergarten are able to understand the whole process, from the 3D scanning of objects, to the customization through 3D modeling and to the modified object 3D printed. In addition, it has been found that playfulness and creativity are enhanced by the mediated use of 3D technologies.
93

Effect of a material science course on the perceptions and understanding of teachers in Zimbabwe regarding content and instructional practice in design and technology

Kwaira, Peter January 2007 (has links)
Philosophiae Doctor - PhD / The purpose of this study was therefore to address the following primary research question: ‘What effect would a specially designed, developed, implemented and evaluated Material Science (MS) course have on serving teachers in terms of their perceptions and knowledge/understanding regarding content in MS and instructional practice in D&T?’
94

Výroba prototypu lovecké kuše / Production of a hunting crossbow prototype

Ventruba, Petr January 2021 (has links)
This master's thesis deals with the manufacturing of a hunting crossbow prototype. The first part summarizes the history of crossbows, their historical development and usage. The following chapter contains theoretical knowladge about the technological methods that are used in the production. This is followed by a designing of the prototype, creating a technological process and final production. Final part of this thesis evaluates individual parts of the production and the final prototype.
95

O uso do design e das tecnologias 3D na criação do repositório digital de elementos de fachada dos prédios históricos da UFRGS

Muniz, Guilherme Resende January 2015 (has links)
As novas tecnologias informacionais mudaram o nosso modo de vida, modificaram nossos hábitos e transformaram profundamente a sociedade. A evolução da informática e da internet trouxe um mundo no qual estamos constantemente conectados através de smartphones, tablets e/ou computadores. Entretanto, na era da informação a velocidade e a facilidade de acesso aos dados, muitas vezes, têm se mostrado superiores à nossa capacidade de absorvê-los e transformar a informação em conhecimento. Neste contexto, novas mídias emergem criando possibilidades de comunicação, dentre as quais destacam-se as tecnologias 3D. Essas abrem novas possibilidades nas mais diversas áreas, oferecendo maior liberdade para que os objetos sejam representados e manipulados no espaço. O campo da educação, por sua vez, tem encontrado dificuldades de absorver estas tecnologias e utilizá-las como ferramentas didáticas. Acredita-se que as tecnologias 3D possam vir a ser importantes instrumentos para a prática pedagógica. O presente trabalho tem como objetivo pesquisar possibilidades de ampliação e facilitação do uso da tecnologia 3D para fins educacionais e de preservação histórica. Para tal, realizou-se uma pesquisa sobre como esta tecnologia tem sido utilizada em ambos os campos. Após, foi realizado levantamento das principais técnicas de digitalização em 3D. Em seguida, foram testadas as principais plataformas e tecnologias para a exibição deste tipo de conteúdo: Cl3ver, Sketchfab, JSC3D, WebGL, Three.js, VRML, X3D, PDF3D e Unity. A partir desta análise, em caráter experimental, criou-se um repositório virtual 3D, o qual encontra-se hospedado nos servidores da UFRGS. O repositório facilita a divulgação de modelos 3D por parte dos criadores deste tipo de conteúdo, pois permite a sua inserção na internet de forma simples, sem a necessidade de conhecimento prévio de programação. Deste modo, o conteúdo gerado pode ser visualizado em computadores e/ou dispositivos móveis, diretamente no navegador, dispensando a instalação de programas complementares, contribuindo para a propagação deste tipo de mídia. Também é possível disponibilizar as obras digitalizadas para reprodução física, mediante técnicas de prototipagem rápida como manufatura aditiva (popularmente conhecida como impressão 3D) e/ou usinagem em CNC. Para a criação do conteúdo 3D, digitalizou-se em três dimensões de quatro elementos, fachadas específicas dos prédios históricos da UFRGS. Os modelos gerados a partir da digitalização foram disponibilizados, através do repositório 3D, e podem ser acessadas no endereço: www.ufrgs.br/ldsm/3d. O repositório 3D dos prédios da UFRGS é uma ação inovadora com propósitos educacionais e de conservação de patrimônio histórico, agindo como catalisador, onde arte, tecnologia e educação convergem em prol da construção do conhecimento. / The new informational technologies have changed our way of life, have changed our habits and profoundly transformed the society. The evolution of computer science and the internet brought a world in which we are constantly connected, whether through smartphones, tablets, and/or computers. However, in this Information Age, the speed and ease of access to data often has been shown to be superior to our capacity to absorb them and to transform the information into knowledge. Within this context, new media has emerged creating new possibilities of communication, among which stand out the 3D technologies, which open up new possibilities in the most diverse areas, offering greater freedom for the objects that are represented and manipulated in space. Fields of education, in this matter, have found difficulties to absorb these technologies and use them as teaching tools. In this context, it is believed that 3D technologies are likely to be important instruments for the pedagogic practice. The present study aims to search possibilities of expansion and facilitation in the use of 3D technology for educational purposes and historical preservation. With this research, it was studied on how this technology has been used in both fields. After this, it was done a survey of the main techniques of 3D scanning. Then, were tested major platforms and technologies for the display of this content type: Cl3ver, Sketchfab, JSC3D, WebGL, Three.js, VRML, X3D, PDF3D and Unity. Trough this analysis, for experimental, purposes was done the creation of a 3D virtual repository which is hosted on the servers of UFRGS. The repository facilitates the dissemination of 3D content by content creators, as it allows its insertion on the Internet in a simple way, without the need for programming skills, so that the content generated can be viewed on computers and/or mobile devices directly in the browser, without the need to install additional programs, contributing to the popularization of this type of media. It is also possible to transform the digitized 3D data creating physical models through rapid prototyping techniques, such as additive manufacturing (popularly known as 3D printing) and/or CNC machining. To create 3D content, 3D scanning was performed of four elements of specific historical UFRGS buildings facades. The models generated from scanning were provided through 3D repository, that can be accessed at: www.ufrgs.br/ldsm/3d. The 3D buildings of UFRGS repository is an innovative action, with educational purposes besides the conservation of historical heritage, acting as a catalyst where art, technology and education converge towards the construction of knowledge.
96

O uso do design e das tecnologias 3D na criação do repositório digital de elementos de fachada dos prédios históricos da UFRGS

Muniz, Guilherme Resende January 2015 (has links)
As novas tecnologias informacionais mudaram o nosso modo de vida, modificaram nossos hábitos e transformaram profundamente a sociedade. A evolução da informática e da internet trouxe um mundo no qual estamos constantemente conectados através de smartphones, tablets e/ou computadores. Entretanto, na era da informação a velocidade e a facilidade de acesso aos dados, muitas vezes, têm se mostrado superiores à nossa capacidade de absorvê-los e transformar a informação em conhecimento. Neste contexto, novas mídias emergem criando possibilidades de comunicação, dentre as quais destacam-se as tecnologias 3D. Essas abrem novas possibilidades nas mais diversas áreas, oferecendo maior liberdade para que os objetos sejam representados e manipulados no espaço. O campo da educação, por sua vez, tem encontrado dificuldades de absorver estas tecnologias e utilizá-las como ferramentas didáticas. Acredita-se que as tecnologias 3D possam vir a ser importantes instrumentos para a prática pedagógica. O presente trabalho tem como objetivo pesquisar possibilidades de ampliação e facilitação do uso da tecnologia 3D para fins educacionais e de preservação histórica. Para tal, realizou-se uma pesquisa sobre como esta tecnologia tem sido utilizada em ambos os campos. Após, foi realizado levantamento das principais técnicas de digitalização em 3D. Em seguida, foram testadas as principais plataformas e tecnologias para a exibição deste tipo de conteúdo: Cl3ver, Sketchfab, JSC3D, WebGL, Three.js, VRML, X3D, PDF3D e Unity. A partir desta análise, em caráter experimental, criou-se um repositório virtual 3D, o qual encontra-se hospedado nos servidores da UFRGS. O repositório facilita a divulgação de modelos 3D por parte dos criadores deste tipo de conteúdo, pois permite a sua inserção na internet de forma simples, sem a necessidade de conhecimento prévio de programação. Deste modo, o conteúdo gerado pode ser visualizado em computadores e/ou dispositivos móveis, diretamente no navegador, dispensando a instalação de programas complementares, contribuindo para a propagação deste tipo de mídia. Também é possível disponibilizar as obras digitalizadas para reprodução física, mediante técnicas de prototipagem rápida como manufatura aditiva (popularmente conhecida como impressão 3D) e/ou usinagem em CNC. Para a criação do conteúdo 3D, digitalizou-se em três dimensões de quatro elementos, fachadas específicas dos prédios históricos da UFRGS. Os modelos gerados a partir da digitalização foram disponibilizados, através do repositório 3D, e podem ser acessadas no endereço: www.ufrgs.br/ldsm/3d. O repositório 3D dos prédios da UFRGS é uma ação inovadora com propósitos educacionais e de conservação de patrimônio histórico, agindo como catalisador, onde arte, tecnologia e educação convergem em prol da construção do conhecimento. / The new informational technologies have changed our way of life, have changed our habits and profoundly transformed the society. The evolution of computer science and the internet brought a world in which we are constantly connected, whether through smartphones, tablets, and/or computers. However, in this Information Age, the speed and ease of access to data often has been shown to be superior to our capacity to absorb them and to transform the information into knowledge. Within this context, new media has emerged creating new possibilities of communication, among which stand out the 3D technologies, which open up new possibilities in the most diverse areas, offering greater freedom for the objects that are represented and manipulated in space. Fields of education, in this matter, have found difficulties to absorb these technologies and use them as teaching tools. In this context, it is believed that 3D technologies are likely to be important instruments for the pedagogic practice. The present study aims to search possibilities of expansion and facilitation in the use of 3D technology for educational purposes and historical preservation. With this research, it was studied on how this technology has been used in both fields. After this, it was done a survey of the main techniques of 3D scanning. Then, were tested major platforms and technologies for the display of this content type: Cl3ver, Sketchfab, JSC3D, WebGL, Three.js, VRML, X3D, PDF3D and Unity. Trough this analysis, for experimental, purposes was done the creation of a 3D virtual repository which is hosted on the servers of UFRGS. The repository facilitates the dissemination of 3D content by content creators, as it allows its insertion on the Internet in a simple way, without the need for programming skills, so that the content generated can be viewed on computers and/or mobile devices directly in the browser, without the need to install additional programs, contributing to the popularization of this type of media. It is also possible to transform the digitized 3D data creating physical models through rapid prototyping techniques, such as additive manufacturing (popularly known as 3D printing) and/or CNC machining. To create 3D content, 3D scanning was performed of four elements of specific historical UFRGS buildings facades. The models generated from scanning were provided through 3D repository, that can be accessed at: www.ufrgs.br/ldsm/3d. The 3D buildings of UFRGS repository is an innovative action, with educational purposes besides the conservation of historical heritage, acting as a catalyst where art, technology and education converge towards the construction of knowledge.
97

Child-centred technologies as learning tools within the primary classroom : exploring the role of tablets and the potential of digital pens in schools

Mann, Anne-Marie January 2017 (has links)
This thesis provides insights into how technology can be and is used as child-centric learning tools within primary school classrooms. The conducted studies look closely at how tablet technology is integrated into the modern classroom, and considers how existing digital writing technologies could support handwriting-based learning exercises in future. This is achieved by conducting three in-the-wild studies, using different approaches, with a total of seventy-four children in school classrooms. In the first study, focus is placed on how tablets integrate into and with existing classroom practices, documenting when and how children use tablets in class. Relevant and complementary to this, the use of traditional writing tools is questioned and two further studies explore the potential and suitability of digital pens to support children's handwriting-based learning. One looks in detail at how children's handwriting is effected by different existing digital pen technologies. The other study, conducted through a creative, participatory design session, asks children to provide their opinions regarding desirable features for digital writing technology. The findings from this research classify and exemplify the role of tablets in the classroom, and explore potential design directions of digital writing tools which could be used by children in the future. This work may be useful and of interest to others who conduct research with children within the fields of Human Computer Interaction, Child Computer Interaction or education.
98

O uso do design e das tecnologias 3D na criação do repositório digital de elementos de fachada dos prédios históricos da UFRGS

Muniz, Guilherme Resende January 2015 (has links)
As novas tecnologias informacionais mudaram o nosso modo de vida, modificaram nossos hábitos e transformaram profundamente a sociedade. A evolução da informática e da internet trouxe um mundo no qual estamos constantemente conectados através de smartphones, tablets e/ou computadores. Entretanto, na era da informação a velocidade e a facilidade de acesso aos dados, muitas vezes, têm se mostrado superiores à nossa capacidade de absorvê-los e transformar a informação em conhecimento. Neste contexto, novas mídias emergem criando possibilidades de comunicação, dentre as quais destacam-se as tecnologias 3D. Essas abrem novas possibilidades nas mais diversas áreas, oferecendo maior liberdade para que os objetos sejam representados e manipulados no espaço. O campo da educação, por sua vez, tem encontrado dificuldades de absorver estas tecnologias e utilizá-las como ferramentas didáticas. Acredita-se que as tecnologias 3D possam vir a ser importantes instrumentos para a prática pedagógica. O presente trabalho tem como objetivo pesquisar possibilidades de ampliação e facilitação do uso da tecnologia 3D para fins educacionais e de preservação histórica. Para tal, realizou-se uma pesquisa sobre como esta tecnologia tem sido utilizada em ambos os campos. Após, foi realizado levantamento das principais técnicas de digitalização em 3D. Em seguida, foram testadas as principais plataformas e tecnologias para a exibição deste tipo de conteúdo: Cl3ver, Sketchfab, JSC3D, WebGL, Three.js, VRML, X3D, PDF3D e Unity. A partir desta análise, em caráter experimental, criou-se um repositório virtual 3D, o qual encontra-se hospedado nos servidores da UFRGS. O repositório facilita a divulgação de modelos 3D por parte dos criadores deste tipo de conteúdo, pois permite a sua inserção na internet de forma simples, sem a necessidade de conhecimento prévio de programação. Deste modo, o conteúdo gerado pode ser visualizado em computadores e/ou dispositivos móveis, diretamente no navegador, dispensando a instalação de programas complementares, contribuindo para a propagação deste tipo de mídia. Também é possível disponibilizar as obras digitalizadas para reprodução física, mediante técnicas de prototipagem rápida como manufatura aditiva (popularmente conhecida como impressão 3D) e/ou usinagem em CNC. Para a criação do conteúdo 3D, digitalizou-se em três dimensões de quatro elementos, fachadas específicas dos prédios históricos da UFRGS. Os modelos gerados a partir da digitalização foram disponibilizados, através do repositório 3D, e podem ser acessadas no endereço: www.ufrgs.br/ldsm/3d. O repositório 3D dos prédios da UFRGS é uma ação inovadora com propósitos educacionais e de conservação de patrimônio histórico, agindo como catalisador, onde arte, tecnologia e educação convergem em prol da construção do conhecimento. / The new informational technologies have changed our way of life, have changed our habits and profoundly transformed the society. The evolution of computer science and the internet brought a world in which we are constantly connected, whether through smartphones, tablets, and/or computers. However, in this Information Age, the speed and ease of access to data often has been shown to be superior to our capacity to absorb them and to transform the information into knowledge. Within this context, new media has emerged creating new possibilities of communication, among which stand out the 3D technologies, which open up new possibilities in the most diverse areas, offering greater freedom for the objects that are represented and manipulated in space. Fields of education, in this matter, have found difficulties to absorb these technologies and use them as teaching tools. In this context, it is believed that 3D technologies are likely to be important instruments for the pedagogic practice. The present study aims to search possibilities of expansion and facilitation in the use of 3D technology for educational purposes and historical preservation. With this research, it was studied on how this technology has been used in both fields. After this, it was done a survey of the main techniques of 3D scanning. Then, were tested major platforms and technologies for the display of this content type: Cl3ver, Sketchfab, JSC3D, WebGL, Three.js, VRML, X3D, PDF3D and Unity. Trough this analysis, for experimental, purposes was done the creation of a 3D virtual repository which is hosted on the servers of UFRGS. The repository facilitates the dissemination of 3D content by content creators, as it allows its insertion on the Internet in a simple way, without the need for programming skills, so that the content generated can be viewed on computers and/or mobile devices directly in the browser, without the need to install additional programs, contributing to the popularization of this type of media. It is also possible to transform the digitized 3D data creating physical models through rapid prototyping techniques, such as additive manufacturing (popularly known as 3D printing) and/or CNC machining. To create 3D content, 3D scanning was performed of four elements of specific historical UFRGS buildings facades. The models generated from scanning were provided through 3D repository, that can be accessed at: www.ufrgs.br/ldsm/3d. The 3D buildings of UFRGS repository is an innovative action, with educational purposes besides the conservation of historical heritage, acting as a catalyst where art, technology and education converge towards the construction of knowledge.
99

Realizace montážní linky ventilů AdBlue / Realization of assembling line for AdBlue valve

Kozelský, Aleš January 2011 (has links)
This diploma thesis concerns in design and realization of assembling line of a 2/2 seat valve for commercial vehicles sector. Design is using Autodesk Inventor. Thesis describes phases and goals of project management – in this case management of technological/manufacturing transfer.
100

Design and Analysis of An Integrated Electrohydraulic Axial Piston Machine

Shanmukh Sarode (6562655) 13 June 2023 (has links)
<p>Emission regulations and global policies to tackle climate change have forced industries and businesses to take measures to curb their impact on the environment. According to the United Nations Environment Program 2022 report on emissions [1], the transportation sector contributes to one-quarter of all energy-related CO2 emissions, and it is set to double by 2050. A recent report [2] suggests that off-road vehicles and equipment account for three-quarters of particulate matter and one-quarter of the nitrogen oxides emitted from mobile transportation sources in the US. The major challenge in decarbonizing or electrifying off-road machines is that they come in a wide range of sizes, weights, and functions, creating barriers to bringing down costs through economies of scale. Fluid power systems which are ubiquitous in these machines have been electrified in a compact and efficient manner to break even the costs of electrification. </p> <p>In off-road applications, where actuation systems heavily depend on hydraulics, there is a high demand for novel systems based on electric prime movers that can enable zero-carbon emission vehicles. An appropriate combination of electric prime movers and hydraulic machines commonly known as electrohydraulic units (EHUs) can help leverage the benefits of both these technologies. The integration of these two technologies in a single casing shaftless EHU can further maximize compactness and reduce cost. However, to achieve such an integrated EHU there is no standard procedure or recommended guidelines for equipment manufacturers owing to the interdisciplinary nature of the problem. </p> <p>This study proposes a generic design methodology to design electrohydraulic units (EHUs). As a starting point, a survey study was undertaken to compare different combinations of electric and hydraulic machines when designing an EHU. The different combinations were investigated for different operating drive cycles for their performance as well as other factors such as power-to-weight, cost, and the possibility of variable displacement. An axial piston machine (APM) was selected as a hydraulic machine (HM) to be integrated with a permanent magnet synchronous motor (PMSM) as the electric machine. </p> <p>The design methodology is demonstrated for an integrated electrohydraulic architecture with the APM housed inside the core of the PMSM. Such an architecture not only makes the overall integration much more compact but also allows for better thermal management of the EM. In such an architecture, the EM governs the overall power density of the integration and the total mass of the integration owing to inherent torque density differences. An EM design optimization is adopted for a predefined HM architecture to design the proposed EHU integration. The design optimization is used to quantify the effect of key EHU design specifications on the EM size and performance. EHU specifications such as sizing torque, operating voltage, aspect ratio, cooling efficacy, number of poles, and power-to-weight ratio have been studied to draw generic trends. These generic trends in the design specifications are used to outline clear guidelines on the impact of each of the EHU specifications for future EHU designers.</p> <p>Using the generic design trends, the design methodology is extended to size the EHU based on typical operating demands using the HM variable displacement, EM overload capability, and the EM flux weakening operation. These sizing studies allow the designers to size the EHU for the specific drive cycle operating demands and avoid oversizing the EHU. The EM flux weakening mode of operation allows the EM to be sized for a peak power level lower than the corner power of operation. The EM overload operation allows a reduction in the sustainable sizing torque lower than that of the maximum torque demand. The variable displacement in the HM can be used for improving overall EHU efficiency when selecting a low voltage or using a compact EM as well as to reduce the EM sizing torque. Two operation algorithms are proposed to define the EHU operation using variable displacement. Additionally, the sizing of a single EHU for multiple applications is also demonstrated. Such multi-utility EHU sizing can promote mass production and improve the rate of electrification in off-road machines.</p> <p>Finally, a prototype-tested EHU design based on the sizing study is demonstrated and the design considerations in such a design process are discussed. The prototype of the integrated EHU with a fixed displacement APM was able to reach the full capability of the reference APM. Thermal considerations are made on the EM sizing, to ensure the reliability of the designed EHU.  A novel self-sustained EHU architecture using the HM working fluid as a cooling fluid for the EM was designed. This was achieved by proposing a three-port valveplate design to divert part of the delivery stroke to cool the EM. A lumped parameter HM model was used to optimize this third port for an EHU prototype.</p>

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