The desire for reduced product flowtime has fueled efforts by companies to implement concurrent engineering within their product development process. While many reductions have been obtained through the production of ...
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The desire for reduced product flowtime has fueled efforts by companies to implement concurrent engineering within their product development process. While many reductions have been obtained through the production of downstream manufacturing data by upstream designprocesses, much improvement could be made through the introduction of detailed manufacturing data requirements into the engineering phase. In particular, the geometric representation requirements of a product can be significantly different between the engineering and the manufacturing phases thus requiting either post-processing of the engineering data or different geometry construction techniques. The engineering drawing likewise must be constructed to be useful for both engineering and yet reflect the realities of part manufacture. These issues are discussed and related to an example intelligent design system implemented at The Boeing Company.
This paper explains design maturity, why it is necessary to evaluate the maturity of designs, at what points in the development process accurate assessment would be most advantageous, and what these advantages might b...
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ISBN:
(纸本)0444897313
This paper explains design maturity, why it is necessary to evaluate the maturity of designs, at what points in the development process accurate assessment would be most advantageous, and what these advantages might be. The paper explains that design maturity assessment is becoming increasingly necessary as companies move towards a Concurrent Engineering (CE) environment. This is in some part caused by the increasing levels of computer integration between functions which can reduce the visibility of the designprocess. Also, the increasingly competitive environment companies operate in requires a continuous reduction in development times through earlier information release to downstream activities both in and outside design, and outside the company when subcontractors are involved in product development. Examination of the structures involved in the design of products indicates where maturity assessment is required. Assessment of the characteristics of designers iterative processes may lead to methods of maturity assessment allowing managers to measure the levels of risk involved in releasing designs. The advantage of accurate maturity assessment would be less design. The bottom line result for companies who can measure their designs' maturity in-process may be a 100% increase in profits per design.
In this research a parametric computer aided design tool is developed for the design and analysis of integrated out of plane plastic snap fasteners. The design tool incorporates automatic parametric mesh generation an...
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In this research a parametric computer aided design tool is developed for the design and analysis of integrated out of plane plastic snap fasteners. The design tool incorporates automatic parametric mesh generation and finite element analysis. This work focuses on automating the integrated plastic snap fastener designprocess by reducing the design cycle time through the integration of manufacturing and structural requirements in the same design cycle. The integrated design problem is posed as finding the optimum shape of the integrated snap fastener that tends toward minimum volume and minimum stress while meeting the process requirements for injection molded parts. The tool is tested in application to three different multiobjective design problems. The results presented highlight the significant improvements that can be obtained when using the computer aided design tool and the flexibility available to a designer in the form of multiobjective design functions.
The designprocess of a mechanical product gathers generally different activities (conceptual study, mechanical analysis, drawing, documentation, manufacture and assembly). Many design systems based on traditional pro...
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Formal methods and verification tools are difficult for designers to use. Research has been concentrated on handling large proofs;meanwhile, insufficient attention has been paid to the reasoning process. We argue that...
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Formal methods and verification tools are difficult for designers to use. Research has been concentrated on handling large proofs;meanwhile, insufficient attention has been paid to the reasoning process. We argue that a heterogeneous logic supporting hardware diagrams and sentential logic provides a natural framework for reasoning and for the formal integration of design and verification environments. We present such a logic and demonstrate its flexibility on fragments of a traffic light controller design and verification problem.
In this work we have explored the problem of automating the construction of a customized femoral prosthesis. We meditate why automated construction of such prostheses can be interesting, both in terms of a rational de...
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ISBN:
(纸本)0819417823
In this work we have explored the problem of automating the construction of a customized femoral prosthesis. We meditate why automated construction of such prostheses can be interesting, both in terms of a rational designprocess, quality assurance, low level optimization and explicit inclusion of design criteria based on the experience developed through evaluation of manual designs. It is demonstrated how design criteria have successfully been given an explicit mathematical description and included in a semi-automatic environment for the extraction of the prosthesis geometry based on a set of digital CT-slices of femur. The mathematical models are integrated in an edge detection framework based on active contours and dynamic programming. A comparison between a manual and the proposed automated designprocess is given.
process planning for machined parts typically requires that a part be described through machining features such as holes, slots and pockets. This paper presents a novel feature finder, which automatically generates a ...
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This paper describes our experiences teaching a freshman design course ME39C using multimedia case studies of engineering design, multimedia tools, and the Internet. Students, in mixed-ability groups, learn design pro...
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This paper describes our experiences teaching a freshman design course ME39C using multimedia case studies of engineering design, multimedia tools, and the Internet. Students, in mixed-ability groups, learn designprocess and practice through reviewing engineering cases on CD-ROM, and using software tools to develop a multimedia case of their own. The curriculum, although having theoretical bases in education research, is highly governed by practical concerns such as rapidly changing technologies, different background experiences of students, and the grading of open-ended work. The course is also driven by new developments in technology and the changing demands of students. In three years, a five person seminar course has evolved into a laboratory of thirty, changing the nature of learning, teaching style, and quality of student work in both positive and negative ways. We describe this course as it progressed from an experimental course to an institutionalized one. Our experiences confirm our belief that curricula should be designed to promote scaffolded knowledge integration by encouraging students to become more independent learners while capitalizing on collaboration and social aspects of learning. Moreover, curricula should be continuously refined and updated to meet the needs of students and reflect advances in technological development toward better preparation in engineering.
Focuses on developing a manufacturable, robust, ion implanted 0.6 /spl mu/m GaAs metal-semiconductor field-effect transistor (MESFET) and metal-semiconductor-metal (MSM) based optoelectronic integrated circuit process...
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Focuses on developing a manufacturable, robust, ion implanted 0.6 /spl mu/m GaAs metal-semiconductor field-effect transistor (MESFET) and metal-semiconductor-metal (MSM) based optoelectronic integrated circuit process. Our approach is to represent the OEIC process as the integration of key process modules. Each process module has well defined design parameters and statistically significant transfer characteristics. The statistically significant transfer characteristics of each process module were obtained throughdesign of experiment (DOE) and response surface modeling (RSM), through the use of both experimental data and calibrated process simulators. These transfer characteristics are used to determine the process optimum, considering design for manufacturability (DFM). The mapping of random process variations onto device variations, are realized by these transfer characteristics and used for statistical circuit design for manufacturability. Therefore, the process yield can be enhanced at both the circuit design and the processdesign levels. The process capability (Cp) is assessed by these modules' transfer characteristics, as well; thus manufacturability can be incorporated into the early stage of process development. As a result, high yield OEIC transmitter and receiver chips with data transmission rates above 1 Gbit/sec have been achieved.
The high operating cost of existing space transportation systems remain a key barrier to the expansion of economic activities in space. Recent technology advances have made possible the design and operation of Reusabl...
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