47 research outputs found
A PSO Application in Skull Prosthesis Modelling by Superellipse
This paper presents a method to create the geometric model of skull defects to be applied in anatomic prosthesis modelling. The approach is to generate an image that represents the missing information in the skull when bone's defect is non-symmetric. We are proposing the use of superellipse concept to recover the parameters that represents the geometric shape of a skull bone curvature in tomography. If the superellipse is properly adjusted in each computed tomography slice, the arcs that represent the piece of missing bone can be modelled in 3D. The problem is that many similar ellipses can be created, and the best solution must be found. This research applies the Particle Swarm Optimization (PSO) algorithm in order to find the best solution for each tomographic slice. Once the solution found for each slice, the whole 3D missing information can be virtually rebuilt as an adjusted prosthesis model image
A PSO Application in Skull Prosthesis Modelling by Superellipse
This paper presents a method to create the geometric model of skull defects to be applied in anatomic prosthesis modelling. The approach is to generate an image that represents the missing information in the skull when bone`s defect is non-symmetric. We are proposing the use of superellipse concept to recover the parameters that represents the geometric shape of a skull bone curvature in tomography. If the superellipse is properly adjusted in each computed tomography slice, the arcs that represent the piece of missing bone can be modelled in 3D. The problem is that many similar ellipses can be created, and the best solution must be found. This research applies the Particle Swarm Optimization (PSO) algorithm in order to find the best solution for each tomographic slice. Once the solution found for each slice, the whole 3D missing information can be virtually rebuilt as an adjusted prosthesis model image
FOREWORD
Foreword to the thematic issue entitled:BIOMEDICAL ENGINEERING - ONE OF THE GREATEST ENGINEERING CHALLENGE
APLICAÇÃO DE PRINCÍPIOS DO DFM NA INDÚSTRIA CERÂMICA: UM ESTUDO DE CASO
O Design for Manufacture é uma filosofia de projeto bastante difundida em diversos ramos da indústria, mas sua aplicação em revestimentos cerâmicos ainda é rara. Por meio de um estudo de caso, este trabalho visou empregar algumas das diretrizes da filosofia de projeto DFM em uma grande fabricante de revestimentos cerâmicos, visando otimizar sua produtividade. Para tal, a metodologia de pesquisa foi divida em quatro etapas: identificação, onde foram investigadas as dificuldades apresentadas pela manufatura; otimização, onde o conceito de melhor projeto foi definido e ações foram tomadas para que se pudesse atingi-lo; verificação, onde o protótipo que mais se aproximou do conceito definido na etapa de otimização foi submetido à manufatura a fim de avaliar se as limitações elencadas na etapa de identificação foram minimizadas; e validação, onde o protótipo foi considerado apto para entrar definitivamente em produção. Ao final, a família de produto porcelanato, identificada como sendo a mais problemática, teve sua estrutura reprojetada e otimizada para maximizar a produtividade da planta industrial. A nova estrutura diminuiu o número de itens utilizados para fabricá-la, reduziu custos e aumentou a produtividade, além de comprovar que o DFM pode ser aplicado à cerâmica
Applying Successive Wave Iterations to Evaluate Functions and Define Industrial Design Solutions
The search for competitive edges in the current industry has required conceptual changes in the policy for the development of new economically, environmentally and socially sustainable products. In this direction, assessing the functions of a product and associating them with its manufacturability aspects has been crucial for the cost reduction and for obtaining a more balanced design regarding the value that the customer perceives and the real cost of manufacturing each one of its functions. However, there are still no relevant studies that present the current state of the art regards methods that iteratively interrelate the integrated product development process phases. Firstly, this paper presents a systematic review and content analysis of recent research to define the current frontiers of study. As a second step, it is proposed a model oriented to balance between function value and solutions cost throughout the new products development. Then, to validate, the proposed model was applied to a real case of the consumer goods industry. Among the results, this chapter presents a report showing the relevance of the information collected, the feasibility of the method, its particularities, impacts and limitations
Manufacturing information interactions in data model driven design
This paper presents a novel view of a software environment that has the potential to provide manufacturing information support to product design in line with the aims of concurrent engineering. The arguments developed should have significant consequences for future computer aided engineering (CAE) systems development and support the continuing globalization in business development. The approach taken has at the centre of its philosophy the need to provide designers with high-quality information on which to base their decisions. The concept of an information supported product design environment is not new, but a range of issues related to information interactions has yet to be resolved. This paper explores the use of information models to support functional and manufacturing interactions in design as well as the issues that are raised in attempting to support multiple views in design for manufacture. The design of injection moulded products is used as the focus against which the ideas in the paper are explored
Semantic interoperability for an integrated product development process: a systematic literature review
International audienceGlobal competitiveness challenges manufacturing industry to rationalise different ways of bringing to the market new products in a short lead-time with competitive prices while ensuring higher quality levels and customisation. Industries need to effectively share heterogeneous information during Product Development Process (PDP) within and across their institutional boundaries to be competitive. However, problems with misinterpretation and mistakes have been identified during information exchange due to the semantic interoperability obstacles. Thus, this research proposes a systematic literature review to identify the main researches and the milestones reference works on semantic interoperability field. A rigorous methodology was conducted in different databases, covering the articles published in scientific journals from 2005 to 2015 as a preliminary study had indicated that the incidence of articles related to the subject was more frequent from the second half of the 2000s. The research structure consisted of four steps: Survey-searching, analysis and selection of recent researches; Categorization-categorization of the selected papers; References citation frequency analysis-the selected papers were analysed and the main researches and milestones references were identified; and Main researches critical analysis – the main researches were analysed for their contributions and limitations, their contributions and limitations, resulting in 14 selected scientific articles and 8 identified milestones references. It is evident that this field has interesting perspectives on future research opportunities on semantic interoperability of information issues across PDP, contributing to the new concepts of future factories
AUTONOMOUS CT REPLACEMENT METHOD FOR THE SKULL PROSTHESIS MODELLING
The geometric modeling of prosthesis is a complex task from medical and engineering viewpoint. A method based on CT replacement is proposed in order to circumvent the related problems with the missing information to modeling. The method is based on digital image processing and swarm intelligence algorithm. In this approach, a missing region on the defective skull is represented by curvature descriptors. The main function of the descriptors is to simplify the skull’s contour geometry; and they are defined from the Cubic Bezier Curves using a meta-heuristic process for parameter’s estimation. The Artificial Bee Colony (ABC) optimization technique is applied in order to evaluate the best solution. The descriptors from a defective CT slice image are the searching parameters in medical image databases, and a similar image, i.e. with similar descriptors, can be retrieval and used to replace the defective slice. Thus, a prosthesis piece is automatically modeled with information extracted from distinct skulls with similar anatomical characteristics
O Gerenciamento de Ferramentas de Corte na Indústria Automotiva: Um Estudo de Casos na Região Metropolitana de Curitiba
Atualmente o cenário econômico mundial exige das empresas agilidade, flexibilidade no atendimento à demanda, foco intenso nos clientes, ciclos de vida de produtos abreviados, desenvolvimento constante de novas tecnologias e o desafio da redução de custos. Na indústria automotiva, onde a complexidade e o alto grau de desenvolvimento tecnológico de seus processos e produtos são significativos, verifica-se, sobremaneira, a necessidade crescente de eliminação de desperdícios e versatilidade em geral. Parcelas significativas dos custos nesse segmento são representadas pelos processos de usinagem de componentes, sendo grande parte desses custos referente ao uso de ferramentas de corte. Nesse contexto, o gerenciamento eficiente de ferramentas de corte torna-se elemento importante para reduzir custos e eliminar desperdícios. O objetivo geral deste trabalho é identificar e debater, sob a ótica da produção enxuta, as principais práticas relacionadas ao gerenciamento de ferramentas de corte na indústria automotiva da cidade de Curitiba e Região Metropolitana, dando ênfase para o planejamento técnico. Observa-se assim que a gestão adequada e inteligente das ferramentas de corte proporciona ganhos relevantes em termos de tempo de manuseio e volume de itens em estoque