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Dimensional Accuracy of Computer-Aided Design/Computer-Assisted Manufactured Orbital Prostheses

MARAFON, Priscila Galzo; MATTOS, Beatriz Silva Camara; SABOIA, Antonio Carlos Lorenz; NORITOMI, Pedro Yoshito
Fonte: QUINTESSENCE PUBLISHING CO INC Publicador: QUINTESSENCE PUBLISHING CO INC
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
78.22343%
Purpose: The aim of this research was to assess the dimensional accuracy of orbital prostheses based on reversed images generated by computer-aided design/computer-assisted manufacturing (CAD/CAM) using computed tomography (CT) scans. Materials and Methods: CT scans of the faces of 15 adults, men and women older than 25 years of age not bearing any congenital or acquired craniofacial defects, were processed using CAD software to produce 30 reversed three-dimensional models of the orbital region. These models were then processed using the CAM system by means of selective laser sintering to generate surface prototypes of the volunteers` orbital regions. Two moulage impressions of the faces of each volunteer were taken to manufacture 15 pairs of casts. Orbital defects were created on the right or left side of each cast. The surface prototypes were adapted to the casts and then flasked to fabricate silicone prostheses. The establishment of anthropometric landmarks on the orbital region and facial midline allowed for the data collection of 31 linear measurements, used to assess the dimensional accuracy of the orbital prostheses and their location on the face. Results: The comparative analyses of the linear measurements taken from the orbital prostheses and the opposite sides that originated the surface prototypes demonstrated that the orbital prostheses presented similar vertical...

A framework for a computer aided design system for product oriented manufacturing systems

Silva, Sílvio Carmo; Alves, Anabela Carvalho; Costa, M.
Fonte: ITÜ Isletme Fakültesi Publicador: ITÜ Isletme Fakültesi
Tipo: Conferência ou Objeto de Conferência
Publicado em //2005 Português
Relevância na Pesquisa
98.42468%
In this paper we present a framework and an associated support system for the design of Product Oriented Manufacturing Systems (POMS). This includes the characterization and description of the structure and components of the support system, including database, user interface and knowledge base. The framework components are integrated into an organized system called CADS_POMS (Computer Aided Design System for POMS).

A computer aided design system for product oriented manufacturing systems reconfiguration

Silva, Sílvio Carmo; Alves, Anabela Carvalho; Costa, M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Parte de Livro
Publicado em //2005 Português
Relevância na Pesquisa
98.52783%
Product Oriented Manufacturing Systems (POMS) are systems designed for variable product demand markets, and dynamically reconfigured for the manufacture of a single type of product or a family of similar products at a time. POMS systems can take several forms and result from exploring the use of flexible resources, a variety of new design philosophies, technologies and approaches to manufacture, including Cellular, Lean, Agile, Quick Response and Fit Manufacturing. In this paper a computer aided design system for the design and reconfiguration of POMS is addressed. A characterization and description of the structure and components of the design system, including a database, a user interface and a knowledge base and the description of some important data sets, are presented.

Computer aided design of extrusion forming tools for complex geometry profiles

Gonçalves, Nelson Daniel Ferreira
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Tese de Doutorado
Publicado em 24/01/2014 Português
Relevância na Pesquisa
98.503%
Tese de doutoramento em Science and Polymer Engineering and Composites; In the profile extrusion, the experience of the die designer is crucial for obtaining good results. In industry, it is quite usual the need of several experimental trials for a specific extrusion die before a balanced flow distribution is obtained. This experimental based trial-and-error procedure is time and money consuming, but, it works, and most of the profile extrusion companies rely on such method. However, the competition is forcing the industry to look for more effective procedures and the design of profile extrusion dies is not an exception. For this purpose, computer aided design seems to be a good route. Nowadays, the available computational rheology numerical codes allow the simulation of complex fluid flows. This permits the die designer to evaluate and to optimize the flow channel, without the need to have a physical die and to perform real extrusion trials. In this work, a finite volume based numerical code was developed, for the simulation of non-Newtonian (inelastic) fluid and non-isothermal flows using unstructured meshes. The developed code is able to model the forming and cooling stages of profile extrusion, and can be used to aid the design of forming tools used in the production of complex profiles. For the code verification three benchmark problems were tested: flow between parallel plates...

Layout and process optimisation : using computer-aided design (CAD) and simulation through an integrated systems design tool

Dias, Luís M. S.; Pereira, Guilherme; Vik, Pavel; Oliveira, José A.
Fonte: Inderscience Publicador: Inderscience
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
98.586455%
The design of production and logistic systems is a process of managing both technical and organisational variants in order to identify the best solution for a given system. This paper discusses design issues of production systems that are applied to an internal logistic system in the automotive industry. As far as the production systems design (PSD) is concerned, three basic classes of software tools usually pertain: computer-aided design (CAD), process simulation, and information systems. However, these software tools have been used with low levels of integration. Vik et al. (2010b, 2010c) proposed integrating these software resources in production systems and developed an advanced tool called integrated design of systems (IDS). The proposed IDS tool involves a wide set of functions for the most common tasks of PSD, from conceptualisation to implementation, including systems analysis (P-Q, cluster, and material flow analysis), automatic generation of simulation models, generation of alternatives for the layout of facilities and factories, material flows display, transportation system design, and iterative buffer size specification. The IDS approach takes advantage of simulation, CAD systems, and their integration. This paper will demonstrate the concept and functionalities of the proposed tool in a real industrial case study.; Fundação para a Ciência e Tecnologia

Project-based teaching-learning computer-aided engineering tools

Simões, J.A.; Relvas, C.; Moreira, R.
Fonte: Taylor and Francis Publicador: Taylor and Francis
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
89.04318%
Computer-aided design, computer-aided manufacturing, computer-aided analysis, reverse engineering and rapid prototyping are tools that play an important key role within product design. These are areas of technical knowledge that must be part of engineering and industrial design courses’ curricula. This paper describes our teaching experience of computer-aided tools for product design centred on the development of a proposed project. The pedagogic model, the teaching objectives and methodology are described and discussed. The competencies acquired within the development of the project have stimulated the design and manufacturing of several artefacts within the students’ final-year project. A conceptual vehicle, a washing machine and a tricycle were products designed by students and are presented.

Facilitating Mechanical Design with Augmented Reality

Poh, Y. L.; Nee, Andrew Y. C.; Youcef-Toumi, Kamal; Ong, S. K.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Artigo de Revista Científica Formato: 605165 bytes; application/pdf
Português
Relevância na Pesquisa
78.413145%
By enhancing a real scene with computer generated objects, Augmented Reality (AR), has proven itself as a valuable Human-Computer Interface (HCI) in numerous application areas such as medical, military, entertainment and manufacturing. It enables higher performance of on-site tasks with seamless presentation of up-to-date, task-related information to the users during the operation. AR has potentials in design because the current interface provided by Computer-aided Design (CAD) packages is less intuitive and reports show that the presence of physical objects help design thinking and communication. This research explores the use of AR to improve the efficiency of a design process, specifically in mechanical design.; Singapore-MIT Alliance (SMA)

A Model for Automatic Design of Digital Circuits

Baldwin, Douglas
Fonte: University of Rochester. Computer Science Department. Publicador: University of Rochester. Computer Science Department.
Tipo: Relatório
Português
Relevância na Pesquisa
88.4416%
One of the long-standing goals of the computer-aided design community is to write computer programs that will automatically design circuits from abstract descriptions of their desired behavior. It is now evident that this goal will be met only through a combination of algorithmic and knowledge-based techniques. In previous work I studied combined algorithmic and knowledge-based circuit design, although with emphasis on the knowledge-based aspects. The work described here builds on that foundation, starting with a model of automatic circuit design that indicates how to partition the design task into algorithmic and knowledge-based parts and how to combine implementations of the parts into a single whole. A design for ASP, a powerful circuit design program based on this model, is outlined.

The Quad-CIF Tree: A Data Structure for Hierarchical On-Line Algorithms

Kedem, Gershon
Fonte: University of Rochester. Computer Science Department. Publicador: University of Rochester. Computer Science Department.
Tipo: Relatório
Português
Relevância na Pesquisa
78.156196%
In this paper we describe the quad-ClF tree data structure and its application to hierarchical on-line computer-aided design algorithms. The main idea is to overlay a tree of coordinates on top of the hierarchical representation of an integrated circuit. The coordinate tree enables one to find quickly the set of all objects that intersect a given window. We outline how one can use the data structure in order to implement hierarchical, on-line design rule checking and node extraction. We also describe some applications to plotting.

Auditory Information Design

Barrass, Stephen
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD); Doctor of Philosophy (PhD)
Português
Relevância na Pesquisa
88.74123%
The prospect of computer applications making "noises" is disconcerting to some. Yet the soundscape of the real world does not usually bother us. Perhaps we only notice a nuisance? This thesis is an approach for designing sounds that are useful information rather than distracting "noise". The approach is called TaDa because the sounds are designed to be useful in a Task and true to the Data. ¶ Previous researchers in auditory display have identified issues that need to be addressed for the field to progress. The TaDa approach is an integrated approach that addresses an array of these issues through a multifaceted system of methods drawn from HCI, visualisation, graphic design and sound design. A task-analysis addresses the issue of usefulness. A data characterisation addresses perceptual faithfulness. A case-based method provides semantic linkage to the application domain. A rule-based method addresses psychoacoustic control. A perceptually linearised sound space allows transportable auditory specifications. Most of these methods have not been used to design auditory displays before, and each has been specially adapted for this design domain. ¶ The TaDa methods have been built into computer-aided design tools that can assist the design of a more effective display...

New Approaches to Computer-Aided Drug Design; Neue Anätze für den Computer-gestützten Wirkstoffentwurf

Schumann, Marcel
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
Relevância na Pesquisa
69.234404%
Computer-aided drug design is very important for modern drug discovery. Using a variety of different algorithms, approximations of the binding free energy of chemical compounds to a molecular target can be generated in silico in a very fast and very cheap way, without any need for physical availability of those compounds in this step. Computer-aided drug design thus allows to drastically speed up the task of developing new drugs, strongly reduces costs and enables the rapid testing of new, yet unsynthesized, classes of compounds. In this dissertation, new approaches for computer-aided drug design are presented: a framework for Quantitative Structure-Activity Relationship (QSAR) modeling, a receptor-ligand scoring function and a docking algorithm, a three-dimensional target-specific rescoring procedure and CADDSuite, a software suite that contains all the aforementioned algorithms and a large set of additional, auxiliary tools and algorithms. The QSAR framework provides all necessary steps to generate regression or classification models with high predictive quality: read input, generate molecular descriptors, generate a variety of different regression and classification models, automatically select relevant descriptors and evaluate the quality of models. Using several data sets...

A computational tool for the rapid design and prototyping of propellers for underwater vehicles

D'Epagnier, Kathryn Port.
Fonte: Cambridge Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution, Publicador: Cambridge Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution,
Tipo: Tese de Doutorado Formato: 95 p : ill.
Português
Relevância na Pesquisa
78.385103%
An open source, MATLAB (trademarked)-based propeller design code MPVL was improved to include rapid prototyping capabilities as well as other upgrades as part of this effort. The resulting code, OpenPVL is described in this thesis. In addition, results from the development code BasicPVL are presented. An intermediate code, BasicPVL, was created by the author while OpenPVL was under development, and it provides guidance for initial propeller designs and propeller efficiency analysis. OpenPVL is part of the open source software suite of propeller design codes, Openprop. OpenPVL is in the form of a Graphical User Interface (GUI) which features both a parametric design technique and a single propeller geometry generator. This code combines a user-friendly interface with a highly modifiable platform for advanced users. This tool offers graphical propeller design feedback while recording propeller input, output, geometry, and performance. OpenPVL features the ability to translate the propeller design geometry into a file readable by a Computer Aided Design (CAD) program and converted into a 3D-printable file. Efficient propellers reduce the overall power requirements for Autonomous Underwater Vehicles (AUVs), and other propulsion-powered vehicles. The focus of this study is based on the need of propeller users to have an open source computer-based engineering tool for the rapid design of propellers suited to a wide range of underwater vehicles. Propeller vortex lattice lifting line (PVL) code in combination with 2D foil theory optimizes propeller design for AUVs. Several case studies demonstrate the functionality of OpenPVL...

Virtual Dinosaurs - Developing Computer Aided Design and Computer Aided Engineering Modeling Methods for Vertebrate Paleontology; Virtuelle Dinosaurier - Entwicklung von Modellierungsmethoden für Computer Aided Design und Computer Aided Engineering für die Wirbeltierpaläontologie

Mallison, Heinrich
Fonte: Universität Tübingen Publicador: Universität Tübingen
Tipo: Dissertation; info:eu-repo/semantics/doctoralThesis
Português
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99.13104%
The use of personal computers offers many benefits to researchers compared to conventional methods, not the least of them the easy visualization of three-dimensional (3D) structures. With rapidly increasing computing power, the last few decades have seen the rise of a large number of new applications for many purposes, some of which have been successfully employed for vertebrate paleontology. Here, a description is given on how to use several commercially available computer aided design (CAD) and kinetic/dynamic Computer Aided Engineering (CAE) modeling software programs as tools for paleontological research. The focus rests on the creation and use of 'virtual' bones, for biomechanical analyses and use in reconstruction of entire skeletons, the use of these 'virtual' skeletons as tools for the creation of 3D 'flesh' models, which are helpful in mass estimates, and finally on multi-body kinetic/dynamic modeling, using these 'flesh' models to analyze posture and gait of extinct dinosaurs. Specifically, the following techniques are described, most of which have been newly developed or significantly improved: - Mechanical digitizing of fossil bones using Rhinoceros 3.0® and NURBS curves - Mechanical digitizing of fossil bones using Rhinoceros 3.0® and point clouds - Mounting 'virtual' skeletons from either mechanically digitized bones or CT-based data - Creating 3D 'flesh' models from 'virtual' skeletons - Creating 3D 'flesh' models from laser scan point cloud data of mounted skeletons - Creating 3D 'flesh' models from silhouette drawings of skeletons - Evaluating the accuracy of 2D and 3D reconstructions using 'virtual' skeletons - Modeling posture...

Computer Aided Design Modeling for Heterogeneous Objects

Gupta, Vikas; Kasana, K. S.; Tandon, Puneet
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/04/2010 Português
Relevância na Pesquisa
78.615825%
Heterogeneous object design is an active research area in recent years. The conventional CAD modeling approaches only provide geometry and topology of the object, but do not contain any information with regard to the materials of the object and so can not be used for the fabrication of heterogeneous objects (HO) through rapid prototyping. Current research focuses on computer-aided design issues in heterogeneous object design. A new CAD modeling approach is proposed to integrate the material information into geometric regions thus model the material distributions in the heterogeneous object. The gradient references are used to represent the complex geometry heterogeneous objects which have simultaneous geometry intricacies and accurate material distributions. The gradient references helps in flexible manipulability and control to heterogeneous objects, which guarantees the local control over gradient regions of developed heterogeneous objects. A systematic approach on data flow, processing, computer visualization, and slicing of heterogeneous objects for rapid prototyping is also presented.; Comment: International Journal of Computer Science Issues online at http://ijcsi.org/articles/Computer-Aided-Design-Modeling-for-Heterogeneous-Objects.php

Multiplexing Techniques and Design-Automation Tools for FRET-Enabled Optical Computing

Mottaghi, Mohammad
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2014 Português
Relevância na Pesquisa
78.64061%

FRET-enabled optical computing is a new computing paradigm that uses the energy of incident photons to perform computation in molecular-scale circuits composed of inter-communicating photoactive molecules. Unlike conventional computing approaches, computation in these circuits does not require any electric current; instead, it relies on the controlled-migration of energy in the circuit through a phenomenon called Förster Resonance Energy Transfer (FRET). This, coupled with other unique features of FRET circuits can enable computing in new domains that are unachievable by the conventional semiconductor-based computing, such as in-cell computing or targeted drug delivery. In this thesis, we explore novel FRET-based multiplexing techniques to significantly increase the storage density of optical storage media. Further, we develop analysis algorithms, and computer-aided design tools for FRET circuits.

Existing computer-aided design tools for FRET circuits are predominantly ad hoc and specific to particular functionalities. We develop a generic design-automation framework for FRET-circuit optimization that is not limited to any particular functionality. We also show that within a fixed time-budget, the low-speed of Monte-Carlo-based FRET-simulation (MCS) algorithms can have a potentially-significant negative impact on the quality of the design process...

Solid modeling interactive interface for design drafting

Maruggi, Edward
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
78.66016%
Providing certain Solid Modeling software systems with Computer-Aided Design Drafting facilities allows these systems to produce industry acceptable engineering drawing displays. A method is put forth to provide these facilities through the design and implemention of a two-dimensional interactive graphics package that interfaces with these systems. This allows other graphical and textual elements to be added to displays produced by the Solid Modeling systems.

B-spline surface techniques for solid modeling an application to computer-aided geometric design

Tang, Chi-Ming
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
78.6613%
One important area of Computer-Aided Geometric Design (CAGD) is concerned with the approximation and representation of the surfaces of solid objects. Accurately describing the shape of an object so that the description is useful to designers who must decide how to manipulate it is an important problem. B-spline techniques promise greater versatility in describing complex surfaces than other techniques, thus the B-spline surface is highlighted in the field of constructive solid geometric modeling. A method for drawing complex surfaces by using B-spline techniques is presented. The tensor product surface scheme is developed for constructing sculptured surfaces. Also, the basic principle of multivariate B-splines, i.e., nontensor product surfaces, the light of tomorrow in CAGD, is introduced.

Computer aided design of multiple pulley timing belt drives

Matson, Gary
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
78.64061%
The design of timing belt drive systems involves determining the belt width and belt length. The length of the belt is a geometry problem which requires summing the tangent lines and the arcs comprising the pitch line. The width of the belt is determined by the required loads. A computer program is developed in this project to automate the timing belt design process. The program comes in three versions. Each version chooses a target belt length, moves a specified pulley to achieve that length, then calculates the minimum belt width. The three versions of the program are the batch version, the interactive version, and the McAuto version. The batch and the interactive version are accessed from a standard computer terminal. The McAuto version is linked to the McAuto CAD system at Eastman Kodak Company. The McAuto version creates McAuto menus, selects information from the graphics screen, then draws results on the screen which become part of the design file.

Integration of computer-aided design techniques into the mechanical product development process

Sturnick, Gerard R.
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
98.92924%
Computer-Aided Design (CAD) has been called the most significant advance since the development of electricity. CAD is regarded as being the greatest breakthrough of modern times in the search for ways to improve the Product Development Process. This improvement is provided in terms of bringing to market better quality and higher performance products in a significantly shorter design/development cycle and at a lower cost. A survey of the various computer-aided design techniques is presented as they are currently being applied in the mechanical product development process. The research of these techniques includes the basic system operation from a user's perspective, as well as discussion of the relative productivity improvements possible as compared with prior techniques and alternative approaches. The survey results are then enhanced through a case study of the more widely used CAD techniques available to a product design engineer. A typical benchmark part design of a thermoplastic clutch pawl was created and analyzed on some of the latest commercially available computer-aided design systems. This case study, conducted at Xerox Corporation, consisted of both wire frame, surface and solids geometry model creation, mass properties analysis...

Planificación tridimensional y utilización de férulas Computer Aided Design/Computed Aided Manufacturing en cirugía ortognática

Aboul-Hosn Centenero,Samir
Fonte: Revista Española de Cirugía Oral y Maxilofacial Publicador: Revista Española de Cirugía Oral y Maxilofacial
Tipo: info:eu-repo/semantics/article; journal article; info:eu-repo/semantics/publishedVersion Formato: text/html; application/pdf
Publicado em 01/09/2014 Português
Relevância na Pesquisa
98.62602%
El presente trabajo se centra en explicar las ventajas que aporta la planificación tridimensional (3D) y la confección de férulas quirúrgicas Computer Aided Design/Computed Aided Manufacturing (CAD/CAM) en cirugía ortognática. La digitalización del entorno laboral es una realidad imparable en nuestra sociedad y, en nuestra especialidad, nos proporciona ventajas desde un punto de vista logístico, de precisión diagnóstica y en la confección de férulas quirúrgicas. Las tradicionales férulas quirúrgicas siguen un método de fabricación casi artesanal sometido a errores sistemáticos que se van acumulando a lo largo del proceso. Las férulas CAD/CAM se crean directamente a partir de imágenes que obtenemos de la tomografía computarizada o de la tomografía de haz cónico con lo que acortamos, digitalizamos y estandarizamos el proceso de confección disminuyendo la posibilidad de cometer errores derivados de la confección manual. Las imágenes 3D sobre las que podemos trabajar nos aportan ventajas respecto a la visualización bidimensional (2D) ya que no hay una pérdida de información ni una superposición de estructuras anatómicas. En 3D podemos ver con mayor detalle puntos de referencia difíciles de visualizar en 2D y son imágenes idóneas para el estudio de asimetrías en el plano frontal.