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.

Denna kandidatuppsats handlar om framtagandet av en billig, enkel och lättinstallerad trapphiss med syftet att underlätta tillgängligheten i lägenhetshus för personer med begränsad rörlighet på grund av deras nerver och leder. Befintliga trapphissar, AFS 2008:3 och SS-EN 81-40:2020 har analyserats för att sätta krav som har behövts följas under projektets gång. Efter en noggrann utvärdering av olika drivmekanismer valdes kugghjul och kuggstång som den mest lämpliga mekanismen baserat på de satta kraven. Val och dimensionering av komponenter till trapphissen har gjorts med hjälp av beräkningar och är baserade på kraven. En modell, med tillhörande komponenter, har konstruerats med CATIA. Modellen har simulerats både i SimSolid och CATIA varav optimeringar har gjorts utefter simuleringsresultat, vilka visade sig vara delvis godkända. Slutsatserna visar att noggrann planering, design och optimering av produkten har bidragit till att uppnå målet att skapa en anpassningsbar och lättinstallerad trapphiss. / This bachelor thesis is about the creation of a cheap, simple and easily installed stair lift with the purpose of facilitating the availability in an apartment building for people with limited mobility because of their nerves and joints. Existing stairlifts, AFS 2008:3 and SS-EN 81-40:2020 have been analysed to establish requirements that needed to be followed throughout the course of the project. After carefully validating different drive mechanisms, gear and rack were chosen as the most suitable mechanism based on the established requirements. Selection and dimensioning of components for the stair lift was made with the help of calculations and are based on the requirements. A model, along with its associated components, was constructed using CATIA. The model has been simulated using both Simsolid and CATIA, and optimizations were made based on the simulation results, which proved to be partly valid. The conclusions demonstrate that meticulous planning, design and optimisation of the product have contributed to achieving the set goal of creating an adjustable and easily installed stair lift.

Detta kandidatarbete genomförs i samarbete med Hilfa Sweden AB för att utveckla ett nytt bygelhandtag, med syftet att optimera formsprutningsprocessen, minska materialanvändningen och förbättra ergonomin. Målet med projektet är att designa ett handtag som är mer lämplig för formsprutning, förbättra hållfastheten och göra det mer resurseffektivt samtidigt som det erbjuder en bättre användarkomfort. Processen inkluderar flera steg: en initial förstudie för att definiera grundläggande krav och riktlinjer, en greppanalys för att undersöka hur ergonomin kan förbättras och FEM-analyser för att testa olika koncept och förbättra designen. Slutligen gjordes en granskning av formsprutningsprocessen med hjälp av simuleringar för att säkerställa att det slutliga konceptet är tillverkningsbart i produktion. Projektet utnyttjar datorstödd design och simulering för att iterativt finjustera produktens egenskaper. Det slutgiltiga resultatet är ett optimerat handtag som inte bara uppfyller, utan överträffar de initiala målen. Materialåtgången reducerades med drygt 8% samtidigt som dess hållfasthet förbättrades med lägre uppstådda spänningar och mindre deformation vid belastning. Den nya designen medför en bättre omfattning runt handtaget och principerna för formsprutning följs mer korrekt, vilket gör den mer lämpad för tillverkning. / This thesis is conducted in collaboration with Hilfa Sweden AB to develop a new bridge handle, aiming to optimize the injection molding process, reduce material usage and improve the ergonomics. The goals of the project is to design a handle that is more suitable for injection molding, to make it both stronger and more resource-efficient while offering better user comfort. The process includes several steps: an initial study to define basic requirements and guidelines, a grip analysis to investigate how ergonomics can be improved and FEM analysis to test various concepts and enhance the design. Finally, a validation of the injection molding process was conducted using simulations to ensure that the final concept is manufacturable in production. The project utilizes computer-aided design and simulation to iteratively refine the product's characteristics. The final result is an optimized handle that not only meets but exceeds the initial goals. Material usage was reduced by 8% while its strength improved with lower emerged stresses and less deformation under load. The new design provides better grip around the handle and the injection molding principles are followed more accurately, making it more suitable for manufacturing.

Stålkonstruktioner är väldigt vanligt inom industrin och samhället, och det finns många olika typer av stål där rostfritt stål är en av dem. Idag använder SCA Obbola rostfritt stål till konstruktioner som maskiner, skywalk, och plattformar. På SCA Obbola (Ångcentrl2) finns en ångproducerande reaktor har ett stort elfilter som rengör rökgasen från partiklar så att farliga utsläpp kan undvikas. Plattformar är fastsvetsade i filtret sådan att personalerna kan få åtkomst till maskiner och mätinstrument, men dessa plattformar har börjat att få korrosionsskador. Syftet med detta projekt var att ta fram nya typer av fribärande plattformar som sitter inte i filtret men bärande från marknivå för att undvika (korrosionsinducerat) skador på filtret och personalen. 3D-modeller av de fribärande plattformarna skapades med Computer-Aided Design-mjukvaran Inventor och punktmoln-mjukvaran Recap Pro. Konstruktionerna analyserades med finita elementmetoden för undersökning av hållbarheten med hänsyn till specificerade krav från SCA Obbolas. Vidare utfördes analytiska beräkningar, och de analytiska resultaten jämfördes i efterhand med FEM-resultaten. Slutligen undersöktes vilken typ av balkpelare som kunde användas som vertikala pelare för att bära konstruktionerna från marknivå. Resultaten visar att spänningarna på de analytiska och numeriska beräkningarna (i Von Mises) skiljde mellan 0–2 MPa och konstruktionerna vägde ca.1300–1500 kg. Slutsatserna var att hållbara konstruktionerna skapades och 100x100 VKR-rör valdes som vertikala balkpelare för att de klarar av belastningar i både den veka och styva riktningarna valdes. / Steel constructions are very common in industry and the society, and many different types of steels exist, among them is stainless steel. Today SCA Obbola uses stainless steel in various ways, for example machines, skywalks, platforms. At SCA Obbola (Ångcentral2) a steam producing reactor includes a large electric filter to clean the flue gas from particles so that the harmful emissions can be avoided. Platforms are welded to the filter so that the staff has access to machines and sensors, but these platforms have started to show serious corrosion damage. The purpose of this project was to develop a new type of cantilevered platform that is not attached to the filter but levered from ground to avoid (corrosion-induced) damage to the filter and injuries of the staff. 3D-models of the cantilevered platforms were developed using the computer-aided design software Inventor and the point-cloud software Recap Pro. The constructions were analyzed employing finite element method (FEM) to investigate its durability with regards to requirements specified by SCA Obbola. In addition, analytical calculations were performed, and the analytical results were compared with the FEM results. Lastly an investigation of which type of beam-pillar that could be performed as vertical pillars to lever the new constructions was performed. It is shown that the stresses obtained by the analytical and numerical calculations (in Von Mises) differed between 0-2 MPa and the new constructions weight about 1300-1500 kg. In conclusions, durable constructions were developed and 100x100 VKR-pipe that can withstand high loads in both weak and stiff directions was chosen as vertical beam-pillars.

Objekte der Simulation sind textile Strukturen - Geflechte, Maschenwaren und Gewebe. Diese können als Seile, tragende und deckende Strukturen in der Architektur, Bekleidung, im Medizinbereich usw. verwendet werden. TexMind Software beinhaltet mehrere Tools für die Generierung der Geometrie von textilen Strukturen und die Durchführung von einzelnen Berechnungen und Simulationen. Beispiele aus den Bereichen Flechten und Maschenware werden gezeigt. Neben den Vorteilen und der Möglichkeiten wird auch eine kritische Übersicht der offenen Punkte dargestellt. Möglichkeiten für Export zu FEM, CFD und CAD Software und solcher für Computer-Animationen werden demonstriert.