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1 – 10 of 325The purpose of this paper is to determine as to develop a fuzzy multi-criteria decision-making (MCDM) algorithm with self-check capability that can solve any manufacturing…
Abstract
Purpose
The purpose of this paper is to determine as to develop a fuzzy multi-criteria decision-making (MCDM) algorithm with self-check capability that can solve any manufacturing company's printed circuit boards (PCB) design computer aided design (CAD) tool selection problem and to implement it.
Design/methodology/approach
An algorithm that consists of two sub-algorithms that use same inputs and alternative pool is developed, thus self-check capability is introduced. The first sub-algorithm designed as an integration of fuzzy AHP and TOPSIS, where the second sub-algorithm composes of fuzzy analytic network process and TOPSIS. Fuzzy set theory and linguistic variables were utilized to handle uncertainty and usage of verbal expressions, respectively. MATLAB programming language was used for the implementation. The used MCDM methods’ and fuzzy set theory's explanations are given along with the literature review prior to real life application of the developed algorithm.
Findings
A MCDM algorithm with self-check capability is introduced. Moreover, a practical decision aid tool is generated for the usage of the manufacturing companies that are related with PCB design.
Practical implications
A practical computerized MCDM aid tool is generated. Using the tool let the manufacturers, i.e. high-tech device manufacturers, evaluate available PCB CAD design tools with respect to tangible and intangible criteria, and obtain a reliable result.
Originality/value
Self-check capability is incorporated into the decision process. Along with this capability, although the decision-making process takes place in a fuzzy environment, result of the algorithm becomes more reliable than the ones deprived of this characteristic. Furthermore, a practical computerized MCDM aid tool is generated.
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M. Alexander, K. Srihari and C.R. Emerson
A product's design influences its manufacturing process and the associated costs. Consequently, design engineers need to review their designs from a manufacturing perspective…
Abstract
A product's design influences its manufacturing process and the associated costs. Consequently, design engineers need to review their designs from a manufacturing perspective. While ‘Design For Manufacturing’ (DFM) tools often identify the manufacturing problems associated with a design, they would be more effective if these problems could be represented to the designer in terms of a cost value. This research developed a cost estimation tool for the designer in the surface mount printed circuit board (PCB) domain by integrating computer aided design, computer aided process planning (CAPP) and cost estimation techniques using a knowledge based framework. The cost estimation can be done in two design stages. First, an initial approximation of the manufacturing cost can be obtained using information such as the component mix, type of substrate and the size of board. After the detailed design of the PCB has been developed, a more accurate PCB assembly cost can be obtained using computer aided design (CAD) data. Both cost determination strategies would require the generation of a macro‐process plan. The cost advisor considers tangible and intangible factors. This cost advisor and the DFM environment have been developed using C ++ and object oriented programming constructs under the MS Windows operating system.
S.M. Hyslop, P.J. Palmer and D.C. Whalley
Routing efficiency provides an estimate of the compactness of a specific PCB layout in comparison with the theoretical minimum size for the circuit design. This work describes a…
Abstract
Purpose
Routing efficiency provides an estimate of the compactness of a specific PCB layout in comparison with the theoretical minimum size for the circuit design. This work describes a methodology for estimating the routing efficiency of existing PCB layouts from scanned images of either a manufactured PCB or the relevant PCB artwork. Measuring and maximising routing efficiency offers a powerful tool in the drive to minimise the size and cost of a PCB, as it provides a quantitative measure of the need to include costly features such as multiple signal layers and blind (or partial) vias.
Design/methodology/approach
The methodology was proven as a manual method, before implementation as a software tool. This work describes the image processing techniques used to recognise traces and vias and describes how this information is processed to derive substrate utilisation statistics.
Findings
An initial survey suggests that trace routing efficiency has declined through time, indicating that many layouts are larger than necessary, or use more signal layers than are required by routing constraints alone.
Research limitations/implications
This work finds that digital logic circuits follow a more coherent trend than analogue or mixed technology circuits. The results are therefore much more applicable in the digital domain.
Practical implications
As the methodology is implemented using images of PCB layouts, it offers the potential to investigate the performance of routing capability for current and legacy applications where CAD data are not available.
Originality/value
Where CAD drawings exist, routing efficiency can easily be calculated from the data. However, the methodology for estimating routing efficiency retrospectively from circuit images is believed to be unique, and sidesteps the problems of gaining access to this information.
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The paper highlights some Australian businesses where CAD‐CAM hasramifications for the quality of goods produced. Since this technologyconstitutes the core of flexible automation…
Abstract
The paper highlights some Australian businesses where CAD‐CAM has ramifications for the quality of goods produced. Since this technology constitutes the core of flexible automation, it eliminates direct human involvement with certain aspects of product and process design, and production. Therefore, the outcomes are more predictable. Reviews are presented of the various dimensions of quality and the potential benefits of CAD‐CAM. There is also some discussion of TQM and the tendency to focus on shopfloor (consistent) conformance to given product specifications, in contrast to recent attempts to emphasise design, because it offers more scope for gaining competitive advantage. The empirical evidence indicates that CAD‐CAM has indeed had a greater impact on preproduction activities, and toolmaking in particular, than on factory operations. Also, styling is very significant in the context of quality enhancement. The ability to machine to closer dimensional tolerances may have been somewhat oversold in this respect, unless the definition covers raising productivity through “getting it right first time”.
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This paper, which will be published in two parts in consecutive issues of Circuit World, reproduces a chapter of the recently published book ‘Handbook of Printed Circuit…
Abstract
This paper, which will be published in two parts in consecutive issues of Circuit World, reproduces a chapter of the recently published book ‘Handbook of Printed Circuit Technology: New Processes, New Technologies’, edited by G. Herrmann and K. Egerer and published by Electrochemical Publications Ltd, Port Erin, Isle of Man.
David R. Selviah, Andy C. Walker, David A. Hutt, Kai Wang, Aongus McCarthy, F. Anibal Fernández, Ioannis Papakonstantinou, Hadi Baghsiahi, Himanshu Suyal, Mohammad Taghizadeh, Paul Conway, John Chappell, Shefiu S. Zakariyah, Dave Milward, Richard Pitwon, Ken Hopkins, Malcolm Muggeridge, Jeremy Rygate, Jonathan Calver, Witold Kandulski, David J. Deshazer, Karen Hueston, David J. Ives, Robert Ferguson, Subrena Harris, Gary Hinde, Martin Cole, Henry White, Navin Suyal, Habib ur Rehman and Chris Bryson
The purpose of this paper is to provide an overview of the research in a project aimed at developing manufacturing techniques for integrated optical and electronic interconnect…
Abstract
Purpose
The purpose of this paper is to provide an overview of the research in a project aimed at developing manufacturing techniques for integrated optical and electronic interconnect printed circuit boards (OPCB) including the motivation for this research, the progress, the achievements and the interactions between the partners.
Design/methodology/approach
Several polymer waveguide fabrication methods were developed including direct laser write, laser ablation and inkjet printing. Polymer formulations were developed to suit the fabrication methods. Computer‐aided design (CAD) tools were developed and waveguide layout design rules were established. The CAD tools were used to lay out a complex backplane interconnect pattern to meet practical demanding specifications for use in a system demonstrator.
Findings
Novel polymer formulations for polyacrylate enable faster writing times for laser direct write fabrication. Control of the fabrication parameters enables inkjet printing of polysiloxane waveguides. Several different laser systems can be used to form waveguide structures by ablation. Establishment of waveguide layout design rules from experimental measurements and modelling enables successful first time layout of complex interconnection patterns.
Research limitations/implications
The complexity and length of the waveguides in a complex backplane interconnect, beyond that achieved in this paper, is limited by the bend loss and by the propagation loss partially caused by waveguide sidewall roughness, so further research in these areas would be beneficial to give a wider range of applicability.
Originality/value
The paper gives an overview of advances in polymer formulation, fabrication methods and CAD tools, for manufacturing of complex hybrid‐integrated OPCBs.
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Earl Moon of Viking Interconnect Systems addressed those present at the 21 May meeting on the subject of ‘Characterisation of Military SMT/MLB Requirements as a Function of the…
David Sanders, Yong Chai Tan, Ian Rogers and Giles E. Tewkesbury
The purpose of this paper is to present a multi‐expert system that can provide designers with suggestions for improvement. The multi‐expert system can analyse a design and provide…
Abstract
Purpose
The purpose of this paper is to present a multi‐expert system that can provide designers with suggestions for improvement. The multi‐expert system can analyse a design and provide designers with ideas for changes to designs at an early stage in order to improve assembly later in the manufacturing process.
Design/methodology/approach
The whole system consists of four expert systems: computer‐aided design (CAD) expert, automated assembly expert, manual assembly expert and design analysis expert. The design analysis expert includes a sub‐system to collate the information from the assembly experts and to provide costs and advice.
Findings
The paper finds that the approach and the systems can reduce manufacturing costs and lead times.
Research limitations/implications
A knowledge‐based reckoning approach to design‐for‐assembly automation is used. The approach and systems can reduce manufacturing costs and lead times. The system can estimate assembly time and cost for manual or automatic assembly and select suitable assembly techniques.
Practical implications
The system can estimate assembly time and cost for manual or automatic assembly and select a suitable assembly technique.
Originality/value
The new system models assembly, product and process design using a natural approach for capturing intelligence. The new approach categorised automated assembly and manual assembly into separate individual experts. Intelligence and knowledge from each is captured and embedded within the individual expert that represented the process. This approach enabled greater flexibility and made the sub‐systems easier to modify, upgrade, extend and reuse.
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W. Shin, K. Srihari, J. Adriance and G. Westby
Surface mount technology (SMT) is being increasingly used in printed circuit board (PCB) assembly. The reduced lead pitch of surface mount components coupled with their increased…
Abstract
Surface mount technology (SMT) is being increasingly used in printed circuit board (PCB) assembly. The reduced lead pitch of surface mount components coupled with their increased lead count and packing densities have made it imperative that automated placement methods be used. However, the SMT placement process is often a bottleneck in surface mount manufacturing. A reduction in placement time in SMT will enhance throughput and productivity. This paper describes the design and development of a prototype expert system based approach which identifies ‘near’ optimal placement sequences for surface mount PCBs in (almost) realtime. The software structure used integrates a knowledge based system with an optimisation module. PROLOG is the language used in this research. The system was rigorously validated and tested. Ideas for further research are also presented.
Haitian Zou, Baolin Wang, Fumin Song and Lianyu Fu
The purpose of this paper is to verify the feasibility and reliability of mineral casting applied in high-precision printed circuit board (PCB) drilling machine. The mechanical…
Abstract
Purpose
The purpose of this paper is to verify the feasibility and reliability of mineral casting applied in high-precision printed circuit board (PCB) drilling machine. The mechanical properties of machine frame are quantified to provide a solution for machine tool industry to seek a perfect substance competing with classic materials such as cast iron and granite.
Design/methodology/approach
The optimal design of machine frame is performed via the CAD system combined with finite element analysis (FEA). The mechanical properties of the frame elements are evaluated by a series of mechanical experiments: static performance is quantified by flatness tests, dynamic behavior is estimated by experimental and numerical models, respectively. Meanwhile, the performance of the frame element with traditional materials is examined experimentally.
Findings
Mineral casting parts can be successfully applied to PCB drilling machine to meet high accuracy requirements. The characteristic of mineral casing gives the most possibilities in structural design. The frame parts show good static/dynamic behaviors by structural optimization processes. Especially, the machine frame with mineral casting gains a great weight reduction compared with traditional materials.
Originality/value
The application of mineral casting in PCB drilling machine offers greater design flexibility and innovative system solutions. The combination of FEA is convincing to achieve optimal structure and ideal weight to maximize the economic and technical benefits. Moreover, lightweight design of machine structural components achieves not only higher kinematic/dynamic precision but also considerable cost reduction.
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