| 1. |
- Asp, Leif, et al.
(författare)
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Multiscale modelling of non-crimp fabric composites
- 2012
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Ingår i: Proceedings of the ASME International Mechanical Engineering Congress and Exposition--2012. - New York : American Society of Mechanical Engineers. - 9780791845196 ; , s. 581-590
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Konferensbidrag (refereegranskat)abstract
- Damage initiation and evolution in NCF composites leading to final failure includes a multitude of mechanisms and phenomena on several length scales. From an engineering point-of-view a computational scheme where all mechanisms would be explicitly addressed is too complex and time consuming. Hence, methods for macroscopic performance prediction of NCF composites, with limited input regarding micro- And mesoscale details, are requested. In this paper, multi-scale modelling approaches for in-plane transverse strength of NCF composites are outlined and discussed. In addition a simplistic method to predict transverse tensile and compressive strength for textile composites featuring low or no fibre waviness is presented.
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| 2. |
- Dagman, Andreas, 1976, et al.
(författare)
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TOWARD A METHOD FOR IMPROVING PRODUCT ARCHITECTURE SOLUTIONS BY INTEGRATING DESIGNS FOR ASSEMBLY, DISASSEMBLY AND MAINTENANCE
- 2012
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Ingår i: Proceedings of the ASME 2012 International Mechanical Engineering Congress and Exposition. - New York : American Society of Mechanical Engineers. - 9780791845196 ; 3:PARTS A, B, AND C, s. 377-387
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Konferensbidrag (refereegranskat)abstract
- New customer demands and increased legislation drive business-oriented companies into new business models focusing on the entire life cycle of the product. This forces the manufacturing companies into service-oriented solutions as a compliment to the original business areas. Takata [1] postulates that “the goal is no longer to produce products in an efficient way, but rather to provide the functions needed by society while minimizing material and energy consumption”. This new situation affects the product requirements as well as product development process (PD). When focusing on the entire product life cycle, product aspects such as maintenance and repair will receive more attention since the companies will be responsible for them. In the product development process of today, especially in the automotive industry, maintenance and repair aspects (repair and maintenance methods and manuals, for example) are currently taken care of when the product is more or less fully developed. Maintenance and repair requirements are difficult to quantify in terms of core product properties (for vehicles, cost, CO2 emissions, weight, and so on). This leads to difficulties in equally considering maintenance and repair requirements while balancing vast amounts of product requirements. This paper focuses on a comparison and discussion of existing design guidelines affecting the structure and organization of parts in an assembled consumer product, such as Design for Assembly (DFA), Design for Maintenance (DFMa), Design for Service (DFS) and Design for Disassembly (DFD) methods. A tool for evaluation and analyzing product architecture as well as assemblability and maintainability is proposed.
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| 3. |
- Edholm, Peter, 1974, et al.
(författare)
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Geometrical Coupling Analysis to Reduce Complete Assembly Line Complexity
- 2012
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Ingår i: Proceedings of the ASME 2012 International Mechanical Engineering Congress & Exposition, IMECE2012, November 9-15, 2012, Houston, Texas, USA. - 9780791845196 ; 3:PARTS A, B, AND C, s. 89-96
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Konferensbidrag (refereegranskat)abstract
- Modern assembly lines for mass production need to fulfill several important criteria. One of them is to produce products with high geometrical quality (small geometric variation). For sheet metal assemblies, focused on in this paper, it is a very complex process to achieve good geometrical quality due to the large number of assembly steps and the geometrical variation (tolerances) of the incoming parts. One “golden rule” for sheet metal assembly lines is to always reuse fixturing points (locators) throughout the whole assembly line to minimize the geometrical variation and also the complexity of root cause analysis.A new method to measure the complexity in an assembly line has been developed and also implemented in a commercial software for Computer Aided Tolerancing. This new tool not only demonstrates the “golden rule” but could also be used to ensure minimum geometrical complexity in assembly lines to ensure controlled production and high quality products.
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| 4. |
- Karlberg, Magnus, et al.
(författare)
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Simulation driven processing function development, offering and operation
- 2012
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Ingår i: Proceedings of the ASME 2012 International Mechanical Engineering Congress & Exposition IMECE2012. - New York : American Society of Mechanical Engineers. - 9780791845196 ; , s. 1561-1572
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Konferensbidrag (refereegranskat)abstract
- In today’s industry, functional provision is becoming more and more important, necessitating increased simulation support. In this paper, the objective is to present a modeling and simulation approach for simulation-driven design (SDD) to support function development. The scope of this paper is simulation support for developing hardware equipment used in processing industry. The research is founded on industrial needs identified through two parallel interview-based studies in the Swedish process industry. Both companies explore doing business with functional products rather than hardware, in scenarios where the responsibility for and availability of the functions may remain with the service provider. One as-is and one future (to-be) scenario are presented. A decomposition of a general processing function (applicable to both companies) describes how the companies transfer machine input to output specifications. The decomposition includes customer and provider value and the paper demonstrates, as part of the results and based on the SDD approach, how that value may be increased through evaluation and prioritization. Additionally, the SDD approach shows that it is possible to identify a set of solutions which meet the specified requirements, supporting evaluation and prioritization of business offers and activities.
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| 5. |
- Lindau, Björn, 1961, et al.
(författare)
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Using Forming Simulation Results In Virtual Assembly Analysis
- 2012
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Ingår i: Proceedings of the ASME 2012 International Mechanical Engineering Congress & Exposition, IMECE2012. - 9780791845196 ; 3:PARTS A, B, AND C, s. 31-38
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Konferensbidrag (refereegranskat)abstract
- In Car Body Assembly Shops, Body in White (BIW), non-rigid sheet metal panels are assembled into car bodies. Depending upon the achieved degree of robustness in part and tool design, the produced items tend to deviate more or less from their nominal specifications. Catching eventual non-robust solutions early on in the development phases is important to minimize time-consuming, expensive testing and trimming activities late in the development- and industrialization phases. To meet these demands, there is today an increased use of virtual forming and assembly tools within the automotive industry. Significant amounts of research have been performed in the area of forming and assembly simulations, but there is still a need to find efficient working methods.This study has focused upon how forming simulation results can be used in virtual assembly analysis. The predicted springback shapes (offset and variation) of the stamped panels are used in the assembly simulation to study the effects of the part variation when assembled, producing a sub-assembly. The method used is described, and the simulation results are reported. The case shows the potential of using forming simulation results in virtual assembly analysis. Furthermore, the strength of using the Principal Component Analysis technique to describe the part variation in assembly simulations is shown.
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| 6. |
- Petersson, Håkan, et al.
(författare)
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A computer-based design system for lightweight grippers in the automotive industry
- 2012
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Ingår i: Proceedings of the International Mechanical Engineering Congress & Exposition - IMECE'12. - New York : ASME Press. - 9780791845196 ; 3 - Part A, s. 169-179
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Konferensbidrag (refereegranskat)abstract
- This paper presents the development as well as the architecture of a computer-aided dedicated fixture design system intended to support the design of lightweight (carbon fiber composite) grippers for a major truck company. Lightweight grippers were required due to the increasing production rates in the automotive industry. The current robotic equipment was facing diverse problems during transportation and aligning of the parts, problems related to mass inertia, accuracy and stability. Moreover, the increased demands for truck customization and fast release of new product versions required a computer-based support for the design of the appropriate fixtures. This application is believed to be of interest for fixture research because the design of such complex fixtures is likely to appear more and more often. Specifically, such fixtures are subject to specific requirements that necessitate a systematic requirement elicitation method; they also require extensive conceptual design work as well as careful analysis activity planning. The main steps requisite for the development of the design system are reported: setup planning, fixture planning, conceptual design of the gripper. The architecture, the process and the constituent elements of the design system are also described and illustrated.
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| 7. |
- Rosenqvist, Mikael, 1975, et al.
(författare)
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Robust design and geometry assurance considering assembly ergonomics
- 2012
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Ingår i: Proceedings of the ASME 2012 International Mechanical Engineering Congress & Exposition IMECE2012, Nov. 9-15, 2012, Houston, Texas, USA. - 9780791845196 ; 3:PARTS A, B, AND C, s. 97-104
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Konferensbidrag (refereegranskat)abstract
- The objective of this study was to explore how assemblyergonomics issues were regarded by geometry engineers.Therefore, 21 geometry engineers in two manufacturingcompanies were interviewed. Their answers show goodawareness of the implications of poor assembly ergonomics butappropriate working procedures and support in CAT (ComputerAided Tolerancing) tool are missing. 95% of the respondentswould like to add consideration to assembly ergonomics in theirCAT simulation. Based on this study a number of assemblyfactors that need to be included and considered in locatingscheme definition and geometric stability analysis are identifiedand presented. Altogether, the results show a need fororganizational change and CAT tool development.
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| 8. |
- Wärmefjord, Kristina, 1976, et al.
(författare)
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A Fixture Failure Control Chart For Variation Caused By Assembly Fixtures
- 2012
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Ingår i: roceedings of the ASME 2012 International Mechanical Engineering Congress & Exposition, IMECE2012, Houston, Texas, USA. - 9780791845196 ; 3:PARTS A, B, AND C, s. 1807-1814
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Konferensbidrag (refereegranskat)abstract
- In the auto body assembly process, fixtures are used to position parts during assembly and inspection. If there is variation in the positioning process, this will propagate to the final assembly. There are also other sources of variation in the final assembly, such as variation in parts due to previous manufacturing steps. To facilitate the separation of the different sources of variation, and thereby also improve fault diagnosis, a fixture failure subspace control chart is proposed. This control chart is based on a multivariate T2-chart, but only variations in the fixture failure subspace are considered. The method is applied to two industrial case studies with satisfying results.
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