Call number: LD2668 .T4 1985 C348 / Master of Science

The problem of using a computer to control the figuring of an optical surface is investigated. By assuming a linear, shift invariant figuring process, the amount of material removed during each figuring run can be computed. This is done by convolving a tool removal profile with a dwell function that describes the amount of time the figuring tool spends in each area element on the surface. Four methods of computing a dwell function that will best remove the figure errors are described. The advantages of making surface figure measurements using direct wavefront measurement techniques over the interferogram analysis methods used in previous computer controlled figuring machines are also discussed. The design and construction of a computer controlled optical figuring machine is then reviewed. The machine uses a computer controlled heterodyne interferometer to provide optical testing data on the surface being polished. Two microcomputers are used to analyze the test data and run the machine. Optical figuring is performed by scanning a polishing head with a known removal function over the surface at a rate derived from the surface errors. The operation of the software that computes the run path data and controls the machine hardware is outlined. The performance of each of the machine components is evaluated by comparing the behavior predicted by theory to the measured behavior. Initially, the accuracy of the interferometer is measured. The interferometer is then used to determine the performance of the polishing head by measuring the tool removal function. It is then shown that the machine can be run so that a predictable amount of material is removed from the surface. Finally, the feedback loop is closed and surface figure data from the interferometer is used to correctly polish the central region of a 16 inch diameter mirror. It is shown that the surface figure can be predicted with good accuracy over the entire surface. This work concludes with recommendations for improving the machine hardware and for improving the figuring performance near the edge of the surface being polished.

Digitized by Kansas Correctional Industries

Detta examensarbete har utförts på Ovako Bar i Hällefors i syfte att kontrollera möjligheterna att automatisera en slipningsprocess på stänger med ytdefekter. Det största skälet till arbetets uppkomst är de vibrationsskador som uppstår i operatörers händer vilket i sin tur leder till sjukskrivningar. Arbetet inleddes med en nulägesanalys på Kontrollstation 7 för att kontrollera hur processen går till, hur operatörerna upplever situationen och få en större förståelse för situationen. Information om nuvarande utrustning inhämtas i syfte att kunna utvärdera möjligheter. Kontakter med potentiella leverantörer togs också, i syfte att få ytterligare bollplank. Efter nulägesanalysen inleddes förbättringsförslagsprocessen. Lösningar till problemet uppkom ur brainstorming efter kravspecifikationen. De lösningar som blev godkända skickades ut till diverse leverantörer som tidigare kontaktats för vidare idéutbyte och möjlighet till utförande. De leverantörer som kontaktades var IM Teknik och Robotslipning AB. Investeringsanalysen visar att lösningen ”robotslipning med visionssystem” är den mest kostnadseffektiva för att uppnå de krav och önskemål som skulle uppfyllas. / This thesis has been carried out on Ovako Bar in Hellefors in order to check the possibility of automating the manual grinding process on bars with surface defects. The biggest reason for the occurrence of this thesis is the vibration damages in operators' hands, which in turn leads to sick leave. Work began with a current situation analysis of KS-7 to observe how the process works, how operators perceive the situation and get a better understanding of the situation as well as acquiring information on the current equipment. Contacts with potential suppliers were taken as well in order to obtain additional exchange about the potential products. After the current situation analysis the improvement suggestions phase took place. Solutions to the problem arose out of brainstorming according to the specifications. The solutions that were approved were sent to various vendors for further exchange of ideas and the possibility of execution. IM Teknik and Robotslipning are the companies that were contacted. Investment analysis shows that the solution with robotic grinding with vision system is the most cost efficient to meet the demands and requirements to be fulfilled.

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The present day manufacturing environment has forced manufacturing systems to be flexible and adaptable to be able to match the product demands and frequent introduction of new products and technologies. This research forms part of a greater research initiative that looks at the development of the reconfigurable manufacturing paradigm. Previous research has shown that the lack of development of a Modular Reconfigurable Manufacturing Tools (MRMT) and Open Architecture Control System (OACS) is currently a key limiting factor to the establishment of Reconfigurable Manufacturing Systems (RMS), which has been the primary motivation for this research. Open Architecture (OA) systems aim to bring the ideas of RMS to control systems for machining systems. An OA system incorporates vendor neutrality, portability, extendibility, scalability and modularity. The research has proposed, designed and developed a novel solution that incorporates these core principles allowing the system to be flexible in mechanical and control architectures. In doing so, the system can be reconfigured at any time to match the specific manufacturing functionality required at that time thereby prolonging the lifecycle of the machine via multiple reconfigurations over time, in addition to decreasing the cost of system modifications due to a well-defined modular system. The reconfiguration and machining variance is achieved by the introduction of mechanical and control modules that extend the Degrees of Freedom (DOF’s) available to the system. The OACS has been developed as a modular solution that links closely to the existing mechanical modularity on the RMT to maximize the reconfigurability of the system. The aim was to create a one to one link between mechanical and electronic hardware and the software system. This has been achieved by the addition of microcontroller based distributed modules which acts as the interface between the electro-mechanical machine axes via hardwired signals and the host PC via the CAN bus communication interface. The distributed modules have been developed on different microcontrollers, which have successfully demonstrated the openness and customizability of the system. On the host PC, the user is presented with a GUI that allows the user to configure the control system based on the MRMT physical configuration. The underlying software algorithms such as, text Interpretation, linear interpolation, PID or PI controllers and determination of kinematic viability are part of the OACS and are used at run time for machine operation. The machining and control performance of the system is evaluated on the previously developed MRMT. The performance evaluation also covers the analysis of the reconfigurability and scalability of the system. The research is concluded with a presentation based on conclusions drawn from the research covering the challenges, limitations and problems that OA and RMS can face before MRMT become readily available for industry. / M.Sc.Eng. University of KwaZulu-Natal, Durban 2013.

Software development is of great significance in manufacturing and process industry. Software can, for example, make production more efficient and monitoring easier. In paperboard industry testing the product, that is, paperboard, is important. Testing is done to make sure that the product meets the requirements of the customers who transform the paperboard to packaging products. In the Skoghall paperboard Mill operators make use of a range of different test methods. Since the work pace is high and the product is being continuously tested improvements of the workflow at the laboratory are always of interest.   The aim of this project is to develop a program that connects test instruments at Skoghall Mill’s test laboratory to the Mill’s network. The motivation is to automate part of the work process by removing the step of manually reading measurement values from the test instruments. The scope of this project includes developing software that connects one of the instruments (the Short Span Compression tester [1] or SCT) at the laboratory to the Mill’s network. This program, named TestLink, will work as a proof of concept for connecting instruments using a common interface. The software is constructed using a modular approach forming a platform where an additional instrument can be connected by creating a new module. The software is developed in Visual Studio using C# as the programming language. The software architecture follows the MVVM [2] (Model View ViewModel) design pattern paradigm and WPF [3] (Windows Presentation Foundation) is used to construct the graphical user interface. The result shows that time savings can be made when automating part of the work with the introduction of new software.

This dissertation discusses the application of additive manufacturing technologies for production of a large-scale rapid prototyping machine, which will be used to produce moulds for prototype composite turbine blades for the emerging renewables energy industry within the Eastern Cape region in South Africa. The conceptualization and design of three complete printer builds resulted in the amalgamation of a final system, following stringent theoretical design, simulation, and feasibility analysis. Following the initial product design cycle stage, construction and performance testing of a large-scale additive manufacturing platform were performed. In-depth statistical analysis of the mechatronic system was undertaken, particularly related to print-head locational accuracy, repeatability, and effects of parameter variation on printer performance. The machine was analysed to assess feasibility for use in the mould-making industry with accuracy and repeatability metrics of 0.121 mm and 0.156 mm rivalling those produced by some of the more accurate fused deposition modellers commercially available. The research data gathered serves to confirm that rapid prototyping is a good alternative manufacturing method for wind turbine blade plug and mould production.

PLC kan idag vara det mest använda styrsystemet till industriella applikationer. Verifikation av programmerad PLC-logik är av stort värde och kan göras på olika sätt. ÅF Karlstad vill idag börja se över möjligheter till implementering av Virtual Commissioning som ett alternativ till minskning av ledtider. I det stora hela blev målet för detta projektarbete att i Xcelgo Experior bygga upp en 3D-miljö som liknar en saltvatten-process på Barilla i Filipstad, skriva PLC-logiken i Siemens TIA-portalen och testköra logiken i 3D-miljön. Och av detta kunna ge underlag till eventuella investeringar i denna teknik för ÅF Karlstad. Gränssnittet Xcelgo Experior visade sig var funktionellt och lättarbetat. Dock hann inte programutvecklarna få i stånd den uppdatering av modulkatologen som krävts för att tillräckligt kunna efterlikna Barillas process att det försvarbart skulle kunna verifiera PLC-logiken. Efter överläggande med min handledare på ÅF, Anders Emanuelsson, bestämdes att i stället verifiera logiken visuellt i Siemens HMI.  Då detta projektarbete endast delvis kommer uppfylla de syften och mål som satts kommer istället en verifiering av PLC-logiken för processen att utgöras av Siemens HMI. Dock har användandet och testkörning av mindre skriven kod, anpassat för nuvarande version av Xcelgo, givit en bild av möjligheterna att effektivt validera PLC-logik då en version lämpad mer för den Värmländska industrin kommit.