Product development has both innovative and analytic sides. Starting from the requirements, a design suggestion is generated. In order to assess how well the envisioned design fulfils the requirements, it is sometimes necessary to build a computer model of it for the analysis. The overall motivation of the work presented is to reduce the time spent on creating the model by reusing knowledge gained from developing similar products by suggesting, building and evaluating IT-systems. To verify the systems real design examples, obtained from companies that have participated in the research projects have been used. The work is based on two major application examples. The first, involving the automated geometrical idealisation of die-cast parts (Paper I-III), and the second involving manufacturability of powder metallurgy pressed and sintered parts (Paper IV-VI). The work starts from the point in the product development process where it exists a design suggestion represented as an arbitrary format CAD-model. In the powder metallurgy case the object is to secure that the geometry is suitable for the production process. In the die-casting case the object is to automatically create an idealised version of the model for shell elements meshing. These two tasks have previously been treated as two separate cases, addressed by completely different software. This thesis suggests a common method for addressing the two cases. The method is based on converting the CAD-models, using the geometrical restrictions of the production processes, into a format with a specialised feature structure, parameterisation and construction history using a feature recognition approach. The features are then automatically reconstructed in a target CAD-system. The resulting, specialised CAD-model can be used for automated design and design evaluation purposes, demonstrated in the thesis. The models are therefore called DAR (Design Automation Ready)-models. The DAR-models are useful in that they separate the conversion from the subsequent treatment of the models providing modularisation, flexibility and user insight in the model structure. In that a construction history and parameterisation have be constructed in the target CAD-system, the advanced geometry manipulation and means for knowledge management often provided in modern CAD-systems can be accessed in a transparent and user manageable way. This extends the usefulness of the CAD-systems from involving only interactive work to managing all components sharing the same production process. / Teknologie Doktorsexamen

For many products, the adaptation to customer specifications is essential and requires flexible product design and manufacture while maintaining competitive pricing. Engineering design is often concerned with striking a good balance between product properties, e.g. performance, and the resources required to manufacture and assemble the product. When different courses of action are to be evaluated, even seemingly small changes in customer requirements, product design, and manufacturing properties have to be handled with caution. Small changes can entail products with: low level of conformability with the manufacturing system, highly increased cost, and extended manufacturing lead-time. For most companies, the manufacturing system is a valuable asset that is more or less fixed and only minor adaptations are allowed. This implies that the product design has to be adapted to the manufacturing system to a large extent. Design for producibility (DFP) is the process in which a systematic method is used to reach the required functional properties of the product at the same time as good compliance with the manufacturing system is ensured. The DFP process usually needs to involve several persons simultaneously for the purpose of sharing information and knowledge. For many manufacturing companies, the collaboration between engineering design and production engineering is a critical issue and they have to improve their methods and tools for ensuring and enhancing producibility. This can be achieved by introducing computer-supported design for producibility. The present research is intended to contribute to the development and utilisation of different application systems that can be used as such computer support. The aim is to provide companies with support in application system development and to show how different application systems can be used in a systematic way as means to ensure and enhance producibility. The competitive advantages to gain from introducing computer-supported design for producibility are: product designs with high level of conformability with the production system, shortened manufacturing lead-time, and decreased manufacturing cost. This work contributes to the achievement of these advantages by introducing a framework with principles and models supporting application systems development. Three types of application systems are presented and their practical usefulness is examined, showing practitioners how producibility aspects can be assessed systematically. The main scientific and theoretical contribution of the work comprises: the descriptions concerning how to structure and describe the product and product-related information (manufacturing requirements, costs, process plans and production resources), the foundation of different information models, and the clarification of the models’ interrelationships. This is perceived as a contribution to a better understanding of the domains and how they relate to each other.Design for producibility (DFP) is the process in which a systematic method is used to reach the required functional properties of the product at the same time as good compliance with the manufacturing system is ensured. The DFP process usually needs to involve several persons simultaneously for the purpose of sharing information and knowledge. For many manufacturing companies, the collaboration between engineering design and production engineering is a critical issue and they have to improve their methods and tools for ensuring and enhancing producibility. This can be achieved by introducing computer-supported design for producibility. The present research is intended to contribute to the development and utilisation of different application systems that can be used as such computer support. The aim is to provide companies with support in application system development and to show how different application systems can be used in a systematic way as means to ensure and enhance producibility.

<p>Intensive competition on the global market puts great pressure on manufacturing companies to develop and produce products that meet requirements from customers and investors. One key factor in meeting these requirements is the efficiency of the product development and the production preparation process. Design automation is a powerful tool to increase efficiency in these two processes.</p><p>The benefits of automating the production preparation process are shortened led-time, improved product performance, and ultimately decreased cost. Further, automation is beneficial as it increases the ability to adapt products to new product specifications with production preparations done in few or in a single step. During the automation process, knowledge about the production preparation process is collected and stored in central systems, thus allowing full control over the design of production equipments.</p><p>Three main topics are addressed in this thesis: the flexibility of design automation systems, knowledge bases containing conflicting rules, and the automation of the finite element analysis process. These three topics are discussed in connection with the production preparation process of rotary draw bending.</p><p>One conclusion drawn from the research is that it is possible to apply the concept of design automation to the production preparation process at different levels of automation depending on characteristics of the implemented knowledge. In order to make design automation systems as flexible as possible, the concept of object orientation should be adapted when building the knowledge base and when building the products geometrical representations. It is possible to automate the process of setting up, running, and interpreting finite element analyses to a great extent and making the automated finite element analysis process a part of the global design automation system.</p>

<p>To be more competitive in the market, many companies are trying to speed up the quotation process and quote more attractive prices. Therefore, they have identified a need for support in the quotation process in order to reduce the quotation lead-time and ensure a higher level of accuracy in the cost estimations. The Quotation Calculator, an application program, has been developed as part of the degree thesis which was carried out at AB Norrahammars Mekaniska Verkstad, NMW 2006/07. This Quotation Calculator can be operated to calculate the material and manufacturing costs of a new product.</p><p>NMW has recently acquired licenses for CATIA V5, Dassault Systems, for the purpose of making process planning and NC-programming more efficient. NMW wants to generate the data needed from the machining module for the cost calculations. Hence this project was initiated in order to extract data from CATIA V5 for further use in Quotation Calculator or other computer system in NMW.</p><p>This work has resulted in a system developed with a common hosted programming language to extract and transfer information. The system retrieves model geometry from CAD and information on process planning from CAM, then matches the information in the application for the purpose of cost estimation. The system once developed, is supposed to be used for every new product. For this approach, the relationship of the data from CATIA V5 and the Quotation Calculator has been analyzed.</p><p>Within this thesis, the focus is on production cost estimation. The method used here is programming in Visual Basic Editor to extract information from the machining module in CATIA V5 and then import them to Microsoft Excel. With standard operations, tables of data and several inputs, the cost calculation and hence the quotation process can be automatically implemented. This work has been generated with the Quotation Calculator. With the correct input data to process planning and this new quotation system, the machining time and the costs can be estimated more accurately and easier. The time and cost information is made available for decision making. As a result, the lead time for the quotation process will be shortened and a relatively more attractive price can be quoted to the customers.</p>

Technology scaling in the nanometer era comes with a significant amount of process variation, leading to lower yield and new types of defective parts. These challenges necessitate robust design to ensure adequate yield, and smarter testing to screen out bad chips. Statistical static timing analysis (SSTA) en- ables this but suffers from crude approximation algorithms. This dissertation first studies the underlying theories of timing graphs and proposes two fundamental techniques enhancing the core statistical timing algorithms. We first propose the refactoring technique to capture topological correlation. Static timing analysis is based on levelized breadth-first traversal, which is a fundamental graph traversal technique and has been used for static timing analysis over the past decades. We show that there are numerous alternatives to the traversal because of an algebraic property, the distributivity of addition over maximum. This new interpretation extends the degrees of freedom of static timing analysis, which is exploited to improve the accuracy of SSTA. We also propose a novel operator for computing joint probabilities in SSTA. In many SSTA applications, this is very common but is done using the max operator which results in much error due to the linear approximation. The new operator provides significantly higher accuracy at a small cost of run time. Second, based on the two fundamental studies, this dissertation devel- ops three applications. We propose a criticality computation method that is essential to robust design and test synthesis; The proposed method, combined with the two fundamental techniques, achieves drastic accuracy improvement over the state-of-the-art method, demonstrating the benefits in practical ap- plications. We formulate the statistical path selection problem for at-speed test as a gambling problem and present an elegant solution based on the Kelly criterion. To circumvent the coverage loss issue in statistical path selection, we propose a testability driven approach, making it a practical solution for coping with parametric defects. / text

<p>Flow-based microfluidic biochips constitute an emerging technology for the automation of biochemical procedures. Recent advances in fabrication techniques have enabled the development of these devices. Increasing integration levels provide biochips with tremendous potential; a large number of bioassays, i.e., protocols for biochemistry, can be processed independently, simultaneously, and automatically on a coin-sized microfluidic platform. However, the increases in integration level introduce new challenges in the design optimization and the testing of these devices, which impede their further adoption and deployment.</p><p>This thesis is focused on enhancing the automated design and use of flow-based microfluidic biochips and on developing a set of solutions to facilitate the full exploitation of design complexities that are possible with current fabrication techniques. Four key research challenges are addressed in the thesis; these include design automation, wash optimization, testing, and defect diagnosis.</p><p>Despite the increase in the number of on-chip valves, designers are still using full-custom methodologies involving many manual steps to implement these chips. Since these chips can easily have thousands of valves, manual design procedure can be time-consuming and error-prone, and it can result in inefficient designs. This thesis presents the first problem formulation for automated control-layer design in flow-based microfluidic biochips and describes a systematic approach for solving this problem. Our goal is to find an efficient routing solution for control-layer design with a minimum number of control pins.</p><p>The problem of contamination removal in flow-based microfluidic biochips must also be addressed. Applications in biochemistry require high precision to avoid erroneous assay outcomes, and they are vulnerable to contamination between two fluidic flows with different biochemistries. This thesis proposes the first approach for automated wash optimization for contamination removal in flow-based microfluidic biochips. The proposed approach ensures effective cleaning and targets the generation of wash pathways to clean all contaminated microchannels with minimum execution time under physical constraints.</p><p>Another practical problem addressed in this thesis is the lack of test techniques for screening defective biochips before they are used for biochemical analysis. This thesis presents an efficient approach for automated testing of flow-based microfluidic biochips. The test technique is based on a behavioral abstraction of physical defects in microchannels and valves. The flow paths and flow control in the microfluidic device are modeled as a logic circuit composed of Boolean gates, which allows test generation to be carried out using standard automatic test-pattern generation tools. Based on the analysis of untestable faults in the logic-circuit model, we present a design-for-testability technique that can achieve 100\% fault coverage.</p><p>Finally, this thesis presents a technique for the automated diagnosis of leakage and blockage defects. The proposed method targets the identification of defect types and their locations based on test outcomes. It reduces the number of possible defect sites significantly while identifying their exact locations.</p><p>In summary, this thesis has led to a set of optimization and testing methods for flow-based microfluidic biochips. The results of this research are expected to not only shorten the product development cycle, but also accelerate the adoption and further development of this emerging technology by facilitating the full exploitation of design complexities that are possible with current fabrication techniques.</p> / Dissertation

To be more competitive in the market, many companies are trying to speed up the quotation process and quote more attractive prices. Therefore, they have identified a need for support in the quotation process in order to reduce the quotation lead-time and ensure a higher level of accuracy in the cost estimations. The Quotation Calculator, an application program, has been developed as part of the degree thesis which was carried out at AB Norrahammars Mekaniska Verkstad, NMW 2006/07. This Quotation Calculator can be operated to calculate the material and manufacturing costs of a new product. NMW has recently acquired licenses for CATIA V5, Dassault Systems, for the purpose of making process planning and NC-programming more efficient. NMW wants to generate the data needed from the machining module for the cost calculations. Hence this project was initiated in order to extract data from CATIA V5 for further use in Quotation Calculator or other computer system in NMW. This work has resulted in a system developed with a common hosted programming language to extract and transfer information. The system retrieves model geometry from CAD and information on process planning from CAM, then matches the information in the application for the purpose of cost estimation. The system once developed, is supposed to be used for every new product. For this approach, the relationship of the data from CATIA V5 and the Quotation Calculator has been analyzed. Within this thesis, the focus is on production cost estimation. The method used here is programming in Visual Basic Editor to extract information from the machining module in CATIA V5 and then import them to Microsoft Excel. With standard operations, tables of data and several inputs, the cost calculation and hence the quotation process can be automatically implemented. This work has been generated with the Quotation Calculator. With the correct input data to process planning and this new quotation system, the machining time and the costs can be estimated more accurately and easier. The time and cost information is made available for decision making. As a result, the lead time for the quotation process will be shortened and a relatively more attractive price can be quoted to the customers.

Duomenų bazių valdymo sistema (DBVS) yra pagrindas beveik visų šiuolaikinių informacinių sistemų (IS). Iš esmės kiekvienas verslo, mokslo arba valdžios valdymo procesas remiasi duomenų baze. Interneto plėtra tik paspartino šią tendenciją – šiandien duomenų bazių operacijos yra kiekvieno duomenų pakeitimo didesniuose tinklalapiuose, paieškos arba apsipirkimo internete variklis [1]. Šiuo metu rinkoje yra didelis komercinių ir nemokamų (taip pat ir atviro kodo) duomenų bazių valdymo sistemų (DBVS) pasirinkimas, pavyzdžiui: Oracle, Microsoft SQL Server, IBM DB2, Microsoft Access, MySQL, PostgreSQL. Kiekviena jų turi savo privalumų ir trukumų. Tačiau informacinių sistemų projektavimo eiga, naudojant šias DBVS ir neatsižvelgiant į jų ypatumus, yra panaši: suprojektuojama duomenų bazė (sukuriamos lentelės, nustatomi jų tarpusavio ryšiai), rašomos užklausos, kuriamos (arba generuojamos) duomenų įvedimo/redagavimo formos bei kuriamos duomenų išrinkimo ataskaitos. Ši informacinių sistemų kūrimo tvarka yra nusistovėjusi per daugelį metų. Tačiau DB projektavimo procesas taptų lengvesnis, pakeitus IS projektavimo procesą taip, kad realizacijos metu iš pradžių būtų kuriamos formos, o tik po to iš sukurtų formų būtų generuojama duomenų bazė. Toks IS kūrimo procesas leistų iš dalies automatizuotų DB projektavimą. Be to, galutinai suderinus prototipus su užsakovu, užtektų tik sugeneruoti DB, t.y. nereikėtų iš naujo kurti formų, o sistema sugeneruotų DB bei automatiškai susietų formų laukus... [toliau žr. visą tekstą] / The Data Base Management System (DBMS) is the foundation of almost every modern business information system. Virtually every administrative process in business, science or government relies on a database. There are a lot of DBMS products in our days, such as Oracle, Microsoft SQL Server, IBM DB2, Microsoft Access, MySQL and PostgreSQL. Each of it has their advantages and disadvantages. But the database design process using these DBMS is the same – at the first stage we need to create a database (tables and relationships between them), then we need to create (or generate by using wizard) forms for data input/modification and reports for data selection. However, the database design process would become easier by changing database design process in such a way that at first we create forms and then database is generated from forms data and forms are automatically associated with database tables. The task of research is to extend chosen free open source DBMS by new functions which would enable to develop forms and DB using new methods – automated database generation from forms and automatic forms association with database tables. OpenOffice.org Base DBMS and Java programming language has been chosen for the task implementation. This thesis consists of analysis, design, user manual, experimental and conclusion parts.

The main goal of this thesis is the development of a novel methodology to generate creative solutions at functional level for design tasks without binding solution spaces with designers&rsquo / individual experiences and prejudices. For this purpose, an evolutionary methodology for the conceptual design of engineering products has been proposed. This methodology performs evaluation, combination and modification of the existing solutions repetitively to generate new solution alternatives. Therefore, initially a representation scheme, which is generic enough to cover all alternatives in solution domain, has been defined. Following that, the evolutionary operations have been defined and two evaluation metrics have been proposed. Finally, the computer implementation of the developed theory has been performed. The test-runs of developed software resulted in creative alternatives for the design task. Consequently, the evolutionary design methodology presents a systematic design approach for less experienced or inexperienced designers and establishes a base for experienced designers to conceive many other solution alternatives beyond their experiences.

With both tougher competition and legislations, companies always strive to improve their products while cutting unnecessary costs. This master’s thesis investigates if the after-treatment systems department at the heavy-duty vehicle company Scania CV AB in Södertälje, Sweden can improve their development process by implementing automated FEM pre-processes for welded sheet metal components. The research is based upon theory from various fields within product development, knowledge-based engineering, FEM and design optimization, contributing to an understating of what effects this project could have on the development process as a whole. Large parts of the pre-processes used at the department today were identified as repetitive and suitable for automation. Using a simplified CAD model of an after-treatment system as a case study, a methodology for more efficient FEM pre-processes was developed. The methodology includes changes to the workflow between the design engineer and the CAE engineer as well as a software that automatically meshes welded sheet metal products. First of all, the design engineer inserts lines representing the weld positions in the CAD model and exports the model to the CAE engineer. Hereafter, the CAE engineer simply selects necessary settings for the mesh and launches the developed software that automatically meshes the sheet metal components as well as identifies and meshes the welds. The technique used to mesh the welds in HyperMesh fails for certain weld characteristics, resulting in a robustness of 54 % of the total weld length for the worst case in the case study. These characteristics are welds crossing other welds, welds adjacent to a sharp corner and welds containing a sharp corner. By excluding these problem areas when defining the lines in CATIA, the robustness increases substantially to between 72 % and 88 % of the total weld length in the case study, where the exclusion zones represent 3 % of the total weld length. Based on the case study, the developed methodology could potentially shorten the iterative development process between the design and CAE engineer with a total of 25 %, while the CAE engineer’s tasks in the development process can be cut with up to 60 %. This allows for more time being focused on value-adding tasks, resulting in higher quality products and an increased profit for the company.