An Apple microcomputer and a three axis milling machine are the basis for a CAD/CAM system with the capability of drilling and contour milling operations. The milling machine axes are driven by three stepper motors under the control of the Apple microcomputer and the ISAAC data acquisition module. An interactive part design program using high resolution color graphics has been developed. It employs lines, circles and points to define the geometry for the part. The design is entered at the CRT and stored as a CAM database on the user disc. Once the design is complete it is postprocessed and the milling machine and the Apple are connected through the ISAAC module. The raw part is set up on the mill and control of contouring is by the Apple microcomputer. The software has been designed to operate very similar to the EZCAM interactive part design software available on the Bridgeport CNC Mark II Series milling machine. It has been developed using Applesoft BASIC language and the 6502 Assembly language.

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This dissertation presents a new approach to the generation of integration systems for CAD/CAM application programs which enlists the tools and methodologies of computer aided software engineering, also referred to as CASE. A CASE workbench is described which aids in the design, analysis and automatic generation of program code for the integration of CAD/CAM applications based on a variety of integration models. The requirements and detail design of a CASE integration toolkit, which will be incorporated into the CAD/CAM CASE workbench, is presented. This toolkit assists with the identification of vital information from the CAD/CAM application programs, such as code structure, comment blocks and explicit information about the occurrence and location of variables, arrays and subprograms, that is not normally supplied by compilers or other source code analysis tools. This specialized toolkit helps to quickly acquaint the integration system designer with unfamiliar application programs and greatly assists in the integration process. The information obtained by the CASE integration toolkit is subsequently passed into the CASE design and analysis toolkits and used to assist in the semi-automatic generation of the integration system. As a basis for many of the ideas in this research, a survey of CAD/CAM integration in industry was undertaken. A wide variety of Fortune 500 companies participated in this project, providing important information on current integration methods, problems and needs. A synopsis of the survey questions and responses is presented. Additionally, a new integration model, referred to as the High-level Autonomous Integration Model (HAIM), is also described. The autonomous integration model allows a higher-level of integration than is normally considered through the utilization of the X Window System and database methods. This model includes the transfer of necessary data as well as simultaneous execution of application programs and the ability to share menus and functions between applications. The CAD/CAM CASE workbench and integration toolkit are designed to assist an integration system designer with the tedious tasks necessary in any CAD/CAM applications integration. This is not meant to infer that the workbench allows complete automation of the integration process. A skilled and knowledgeable designer, however, can save a great deal of time through the utilization of the analysis, design and generation capabilities provided by the CAD/CAM CASE workbench. A description of the necessary skills and tasks performed by the systems integration designer is also included. / Ph. D.

This thesis introduces GENMOD, a collection of subroutines which allow automatic geometric modeling of 3-D models for spatial links or linkages given a minimum amount of information as input. The subroutines utilize the CADCD (CADAM, Inc.) geometry interface software to enter 3-D data directly into the CAD/CAM database. Wire-frame and surface models are produced. Input is accepted from user created files with a standardized format allowing the GENMOD subroutines to be implemented regardless of the synthesis and analysis routines used. The realistic visualization of a mechanism during the synthesis and analysis process can help the mechanism designer to eliminate unacceptable linkage configurations in the early design stages thereby saving time and money. A complete description of the subroutines is provided in addition to sample graphic output. / M.S.

This work defines an expert machinability data system integrated with a CAD system, for computing complete machining parameters required for further processing with NC software. The main objective is to move toward the concept of a fully computerized system, from design to the generation of NC code which can be directly sent to a manufacturing unit. A typical example of such a system, MICADEX, is described in this thesis. MICADEX is capable of retrieving geometric description of components from their 2-D CADAM drawings using the IUE (CADAM Access) facilities and making decisions on machining parameters required for the turning operation, in consultation with the user. MICADEX is designed to be a representative example of an intelligent system capable of providing virtual machining facilities on a CAD system, and lt does not require its users to have a high level of engineering skills. / Master of Science

Computer aided design (CAD) software delivered by vendors is seldom complete. Customizing and/or developing new software is inevitable. A recent survey indicates that most companies purchase or write custom computer aided design software tailored to their specific needs. Design of such software requires the development of modeling tools for the creation of CAD geometry. This research investigates the capabilities of the proposed graphics standard, PHIGS plus, as a geometric modeling interface in CAD that off-loads many basic modeling functions to PHIGS. Specifically, how the B-spline modeling capabilities of PHIGS plus can be enhanced through the use of a new modeling interface prototype is examined. This prototype consists of a proposed graPHIGS modeling toolbox based entirely on PHIGS plus concepts. The prototype provides functionality to easily create B-spline curves and surface geometric entities based on data points and continuity constraints. Functionality is also included to easily perform modeling operations on B-spline surfaces such as intersection and trimming. / Master of Science

Traditionally, design geometries are represented using orthographic views which require a human being to interpret them and recognize geometric features to evaluate the design. Solid modeling systems have made the task somewhat easier, but they often require tedious and complex operations using simple geometric primitives. This has led to investigation of modeling systems which allow the creation of assemblies the way engineers conceive them - as features. To be able to efficiently describe models in terms of features, a rich set of feature descriptors are necessary. An exhaustive study of English words describing form, shape, feature, shape altering transformations and surface conditions was done to establish a wide vocabulary for feature based description. Classification based on topology and form was done and prototype constraint relations were implemented to differentiate between some features. A feature is created from a topological group by computing points and interpolating them with uniform rational B-spline patches. Control points needed to compute the patches are computed from the interpolation points by an inverse relation. A designer-oriented modeling language, based on simple English syntax, was devised to specify procedures to be executed by the modeler in order to create features using minimal user input. / Ph. D.

Every year thousands of specialized CAD/CAM applications programs are developed to meet the needs of industry, education and research. The international 3-D graphics standard, PHIGS, has proven to be very useful in the creation of custom CAD/CAM software. Although PHIGS+ promises to deliver some geometric modeling procedures, not nearly enough is being done to support the writing of CAD/CAM software. CAD/CAM applications programmers should have available a standardized high level applications programming environment which supports the creation of device-independent and portable design and manufacturing software. In this dissertation, one approach towards the establishment of a CAD/CAM programming standard has been presented. This programming environment is called CADMADE - Computer-Aided Design and Manufacturing Applications Development Environment. CADMADE includes not only graphics programming support, but also high level procedures to support the creation of geometric modeling, mechanical design, manufacturing, expert systems and user interface software. The requirements of CADMADE have been created. CADMADE consists of five environments: the User Interface Environment (UIE), the Design and Modeling Environment (DME), the Virtual Manufacturing Environment (VME), the Expert Consultation Environment (ECE) and the PHIGS+ Environment. The User Interface Environment has been designed in great detail. A prototype of the User Interface Environment has been created using PHIGS. Examples of applications programs which use the prototype User Interface Environment are presented. The Design and Modeling Environment has also been designed. A new set of logical input/output devices has been created for the Design and Modeling Environment. The requirements of the Expert Consultation Environment and some new concepts in expert system consultation are discussed. / Ph. D.

A tecnologia CAD-CAM vem sendo aplicada há mais de uma década para a confecção de trabalhos protéticos odontológicos e bucomaxilofaciais. A tecnologia de prototipagem rápida permite a construção de um modelo em tempo reduzido por meio do sistema CAD (computer-aided design) e CAM (computer-aided manufacturing), permitindo absoluta fidelidade ou discrepância desprezível. Assim, o objetivo deste trabalho será analisar a viabilidade da aplicação da tecnologia CAD-CAM por prototipagem rápida na confecção de estrutura metálica da prótese parcial removível, comparando-a ao método convencional. O projeto visa à obtenção de melhores benefícios funcionais e econômicos aos pacientes, trazendo à luz inovações tecnológicas, novos conceitos e melhores condições para o restabelecimento da saúde bucal. A metodologia empregada partiu da reprodução de um modelo padrão de uma arcada inferior parcialmente desdentada, classe III Mod-1 de Kennedy. Quatro pilares metálicos foram posicionados no local dos primeiros pré-molares e molares. Com o auxílio de um scanner digital 3D, obteve-se um modelo virtual da arcada, no qual foi modelado digitalmente o desenho da estrutura protética. Oito estruturas de PPR foram confeccionadas utilizando-se a tecnologia de prototipagem rápida e, posteriormente fundidas em liga de cobalto-cromo. Outras oito estruturas foram confeccionadas seguindo o protocolo para confecção de PPR de forma convencional. A análise comparativa foi realizada avaliando o peso perdido. A avaliação por peso está dividida em dois grupos. O primeiro, denominado Grupo AP (Ajuste e Polimento), possui quatro estruturas convencionais (Grupo AP-C) e quatro prototipadas (Grupo AP-P). O segundo, chamado Grupo A (Ajuste) realizado somente ajuste sem polimento, com quatro estruturas convencionais (Grupo A-C) e quatro prototipadas (Grupo A-P). Análise comparativa por peso mensurou a porcentagem de material perdido necessário para o adequado assentamento dos apoios das estruturas metálicas pela técnica convencional e por prototipagem em seus respectivos descansos. Os resultados mostraram que as estruturas foram passíveis de serem obtidas pela tecnologia proposta. A análise comparativa mostrou que o Grupo AP-P apresentou um desgaste médio de 0,9826g, correspondente a 13,5188% de seu peso inicial; o Grupo AP-C apresentou um desgaste médio de 0,7529g, correspondente a 12,4380% de seu peso inicial. A análise por meio de Teste t independente mostrou uma diferença estatisticamente significante com valor de p=0,0386, p<0,05. No Grupo A-P houve um desgaste médio de 0,1045g, correspondente a 1,4455% de seu peso inicial. No Grupo A-C houve um desgaste médio de 0,1473g, correspondente a 2,3188% de seu peso inicial. A análise por meio de Teste t independente mostrou uma diferença estatisticamente significante com valor de p=0,0038, p<0,01. Foi viável a aplicação da tecnologia CAD-CAM por prototipagem rápida na confecção de estrutura metálica da prótese parcial removível. / The CAD-CAM technology has been applied for more than a decade for the manufacturing of dental and maxillofacial prosthesis. The rapid prototyping technology allows for the construction of a model in reduced time by using the CAD (computer-aided design) and CAM (computer-aided manufacturing) systems, allowing absolute preciseness or negligible discrepancies. Thus, the purpose of this research is to analyze the viability of the application of the CAD-CAM technology of rapid prototyping in the manufacturing of removable partial dentures(RPD) compared to the conventional method. The purpose of this research was to obtain functional and financial benefits for the patient, demonstrate recent technological advances and concepts and improve the resources for the reestablishment of oral health. The methodology used to determine effectiveness of the CAD-CAM system started with the reproduction of a Kennedy Class III Modification 1 cast of an inferior partially edentulous dental arch,. Four metallic pins were positioned in place of the first premolars and molars. A 3D scanner was used to construct a virtual model of the arch on which the design of the prosthetic structure was digitally formed. Eight RPD frameworks were manufactured using the fast prototyping technology with subsequent casting with a cobalt-chromium alloy; eight others followed the standard RPD waxing/casting procedure. The analysis between procedures evaluated the weight lost when each of the respective frameworks were processing. The results were divided into two groups. The first group, named AP (Adjusted and Polished), had four standard (Group AP-C) and four prototyped (Group AP-P) frameworks. The second group, named A (Adjusted), also includes eight frameworks (four standard, Group A-C, and four prototyped, Group A-P) which were cast and adjustted but not polished. In the comparative analysis, the variation of the weight determined the percentage of the material lost needed for the adequate settling of the rests in their respective seat with the standard and prototyped methods. The data indicated that frameworks can be obtained with the proposed technology. The comparative analysis results showed an average wear of 0.9826g on Group AP-P, corresponding to 13.5188% of its initial weight. In the Group AP-C, average wear was 0.7529g, 12.4380% of its initial weight. With the independent t-test, a significant statistical difference of p=0.0386, p<0.05 was found. The average wear for Group A-P wasf 0,1045g, 1.4455% of its initial weight, while in Group A-C the value was 0.1473g, corresponding to 2.3188% of its initial weight. The independent t-test analysis for these cases shows a significant statistical difference of p=0.0038, p<0.01. The application of the CAD-CAM technology of fast prototyping is viable for the manufacturing of removable partial dentures.

A disponibilidade da tecnologia CAD/CAM na área biomédica suscitou o desenvolvimento deste trabalho, onde se avalia a estabilidade das dimensões faciais em prótese óculo-palpebral. Tomografias computadorizadas da face de 15 indivíduos voluntários, maiores de 25 anos de idade, não portadores de lesão congênita ou adquirida na região crânio-facial e de ambos os gêneros, foram reformatadas no sistema CAD, gerando imagens espelhadas de 30 modelos tridimensionais da região óculo-palpebral. Estes modelos foram processados no sistema CAM, empregando-se a sinterização seletiva a laser, dando origem a 30 protótipos de superfície. Paralelamente foram realizadas duas moldagens faciais em cada indivíduo, obtendo-se 15 pares de modelos em gesso da face, nos quais foram simuladas lesões óculo-palpebrais padronizadas nos lado direito e esquerdo. Os protótipos de superfície foram adaptados nos respectivos modelos em gesso, removidos e incluídos em mufla para obtenção da prótese óculo-palpebral em silicone. A definição de pontos antropométricos na área da prótese e na linha mediana da face possibilitou o estabelecimento de 31 medidas lineares empregadas para a avaliação da estabilidade das dimensões da prótese óculo-palpebral e de seu posicionamento na face. Fundamentando-se na análise comparativa das medidas observadas no lado da prótese e no lado contra-lateral íntegro que deu origem ao protótipo de superfície, conclui-se que a prótese óculo-palpebral não apresenta alteração de suas dimensões vertical, transversal e oblíqua. Não ocorre alteração na profundidade da prótese óculo-palpebral nos modelos da face, como também a prótese não sofre deslocamento espacial na face nos sentidos transversal e oblíquos. O conjunto das mensurações relativas ao lado da prótese óculo-palpebral não é estável em relação ao conjunto do lado contra-lateral que deu origem a esta prótese. A estabilidade dimensional da prótese óculo-palpebral e o seu posicionamento na face são compatíveis com a utilização em clínica do sistema CAD/CAM avaliado nesta pesquisa. / The CAD/CAM technology available in the biomedical area gave rise to the development of this study in order to evaluate the dimensional stability of orbital prosthesis. Face computerized tomography of 15 adults, men and women older than 25 years of age not bearing congenital or acquired craniofacial defect, were processed in CAD (computer-aided design) software to produce 30 reverse tridimensional models of the orbital region. These models were then processed in the CAM system (computer-aided manufacturing), by means of laser selective sintering, to generate surface prototypes of the orbital region. Two facial impressions of each subject provided 15 pairs of cast models and orbital defects were performed either in the right or left side of each stone model. The surface prototypes were adapted in the casts and then flasked to be processed in silicone. The demarcation of anthropometric landmarks within the prosthesis and in the face midline defined 31 linear measurements, used to evaluate the dimensional stability of the orbital prostheses and its location in the face. In conclusion, the comparative analyses of the measurements, observed in the prostheses and in the opposite sides that originated the surface prototypes, showed that silicone orbital prostheses presented similar vertical, transversal and oblique dimensions, as well as similar depth. There is no transverse or oblique displacement of the prostheses. Combined measurements in the prostheses\' side are not stable regarding the opposite side. The dimensional stability of orbital prostheses suggests that the CAD/CAM system evaluated herein may be used with clinical purposes.