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Assembly is a necessary and important part of any manufacturing process. Computer aided production engineering allows production engineers to create an on‐screen virtual manufacturing environment which graphically displays and simulates actual manufacturing processes. This is an attempt to analyse the assembly process for a computer mouse, using both the Boothroyd and Dewhurst design for assembly (DFA) and Tecnomatix’s Dynamo software package. A mouse designed in Unigraphics has been the product considered and the assembly process has been analysed. Some of the steps involved in the analysis are explained in detail and the observations and results are discussed along with redesign suggestions. These software systems can help identify some of the technical problems that can possibly be encountered in real life production and can effectively be used to guide the design process. Product assembly, analysis and visualization, which are the prime features of the software in use, enable us to improve the design and enhance the features of products at the conception and design stage itself. This can be a critical factor for maintaining a competitive edge in the fast growing industry today.

Describes a systematic procedure for the design of a manufacturing assembly system, which has been developed in response to the problems associated with the allocation of tasks to workstations, under conditions of uncertainties (and, hence, risks) in some key system parameters. Adopts the methodology of stochastic modelling, whereby various probability distributions are integrated within a modified COMSOAL algorithm, as a means of addressing the uncertainties associated with key manufacturing assembly system variables, such as cycle time and task times. The proposed computer‐oriented methodology is code‐named CIMASD, and incorporates four basic objective criteria options: minimizing the number of workstations; minimizing the balance delay; minimizing the cycle time; or a combination of two or more. Discusses four variants of the CIMASD methodology, designed and equipped to reflect on various uncertainty circumstances under which manufacturing assembly system designs are performed in practice. Demonstrates the efficacy of the CIMASD methodology by applying two of its variants to a case study. Shows that the proposed methodology is capable of facilitating far more informative manufacturing system design than would otherwise be possible: CIMASD can incorporate effective cost saving features, which are useful in the planning, designing and scheduling of workstation tasks, in a typical manufacturing assembly system design.

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.

The recent shift towards accommodating flexibility in manufacturing companies and the complexity resulting from product variety highlight the significance of flexible assembly systems and designing products for them. The purpose of this paper is to provide insight into the requirements of a flexible assembly system for product design from the assembly system’s standpoint.

To fulfil the purpose of the paper, a literature review and a case study were performed. The case study was conducted with an interactive research approach in a global market leader company within the heavy vehicle manufacturing industry.

The findings indicate that common assembly sequence, similar assembly interfaces, and common parts are the main requirements of a flexible assembly system for product design which reduce complexity and facilitate various flexibility dimensions. Accordingly, a model is proposed to broaden the understanding of these requirements from the assembly system’s standpoint.

This study contributes to the overlapping research area of flexible assembly systems and product design.

The proposed model is largely based on practical data and clarifies the role of product design in facilitating flexibility in an assembly system. It can be used by assembly managers, assembly engineers, and product designers.

The key originality of this paper compared to the previous studies lies in presenting a novel assembly-oriented design model. The model enhances understanding of a flexible assembly system’s requirements for product design with regard to reducing complexity and managing variation in a flexible assembly system. These requirements can be applied to product design across various product families within a company’s product portfolio.

This study seeks to present a simple assembly line design and its balance for a low‐volume manufacturing company.

The study presents experiences with the design and implementation of a simple assembly line. The implementation concerns three aspects; design and construction of the assembly line, the assembly analysis of the product, and then balancing of the line. It also discusses construction and implementation difficulties of this tactical tool in the case company.

The study presents some outcomes from the design, implementation, and balancing of an assembly line for SMEs.

The study is limited by the case company and its experience.

This study is not pure theoretical study, it has application stages for industry, and it provides some real interface for the people from SMEs.

The approach has an original value in respect of implementation of assembly line for a small manufacturing company which has many limitations.

The purpose of this paper is to present a novel Kriging meta-model assisted method for multi-objective optimal tolerance design of the mechanical assemblies based on the operating conditions under both systematic and random uncertainties.

In the proposed method, the performance, the quality loss and the manufacturing cost issues are formulated as the main criteria in terms of systematic and random uncertainties. To investigate the mechanical assembly under the operating conditions, the behavior of the assembly can be simulated based on the finite element analysis (FEA). The objective functions in terms of uncertainties at the operating conditions can be modeled through the Kriging-based metamodeling based on the obtained results from the FEA simulations. Then, the optimal tolerance allocation procedure is formulated as a multi-objective optimization framework. For solving the multi conflicting objectives optimization problem, the multi-objective particle swarm optimization method is used. Then, a Shannon’s entropy-based TOPSIS is used for selection of the best tolerances from the optimal Pareto solutions.

The proposed method can be used for optimal tolerance design of mechanical assemblies in the operating conditions with including both random and systematic uncertainties. To reach an accurate model of the design function at the operating conditions, the Kriging meta-modeling is used. The efficiency of the proposed method by considering a case study is illustrated and the method is verified by comparison to a conventional tolerance allocation method. The obtained results show that using the proposed method can lead to the product with a more robust efficiency in the performance and a higher quality in comparing to the conventional results.

The proposed method is limited to the dimensional tolerances of components with the normal distribution.

The proposed method is practically easy to be automated for computer-aided tolerance design in industrial applications.

In conventional approaches, regardless of systematic and random uncertainties due to operating conditions, tolerances are allocated based on the assembly conditions. As uncertainties can significantly affect the system’s performance at operating conditions, tolerance allocation without including these effects may be inefficient. This paper aims to fill this gap in the literature by considering both systematic and random uncertainties for multi-objective optimal tolerance design of mechanical assemblies under operating conditions.

Flexible Assembly Systems (FASs) are normally associated with the automatic, or robotic, assembly of products, supported by automated material handling systems. However, manual assembly operations are still prevalent within many industries, where the complexity and variety of products prohibit the development of suitable automated assembly equipment. This article presents a generic model for incorporating flexibility into the design and control of assembly operations concerned with high variety/low volume manufacture, drawing on the principles for Flexible Manufacturing Systems (FMS) and Just‐in‐Time (JIT) delivery. It is based on work being undertaken in an electronics company where the assembly operations have been overhauled and restructured in response to a need for greater flexibility, shorter cycle times and reduced inventory levels. The principles employed are in themselves not original. However, the way they have been combined and tailored has created a total manufacturing control system which represents a new concept for responding to demands placed on market driven firms operating in an uncertain environment.

Highlights growing concerns, raised from both direct company experience and research, about the present industry trend for outsourcing manufacture and assembly to overseas manufacturers, and illustrates the importance of employing “best practice” product design methods.

Details a number of problems, often unexpected, that can be encountered by companies who outsource production overseas, and the additional costs these can incur. It also reports on an alternative to outsourcing, which is better product design, and how this can be achieved through the design for manufacture and assembly methodology.

For many companies the potential benefits of outsourcing overseas, in particular low labour costs, can be quickly roded by hidden, but often encountered, extra costs. Moreover, improving product design through DFMA can offer a viable alternative to outsourcing overseas for some companies.

It is essential that before starting on an outsourcing strategy – or even as a review of an existing strategy – companies not only undertake a full cost benefit analysis of overseas manufacture, but also look at the product design. The fact is – as it always has been – that simpler better designs are more productive, require less labour, and may permit manufacturers to remain more agile and competitive by retaining local manufacture.

Brings to the attention of managers some of the key – often hidden‐problems and cost issues relating to the practice of outsourcing manufacture overseas and revisits the still too often neglected area of developing better products by making them easier to manufacture and assembly.

The purpose of this paper is to explore how integral and modular product architectures influence the design properties of the global operations network.

The authors perform a multiple-case study of three global manufacturing companies, using interviews, seminars and structured questionnaires to identify ideal design properties.

The authors find that the choice of integral vs modular product architecture lead to significant differences in the preferred design properties of global operations networks concerning number of key technologies in-house, number of capable plants, focus at assembly plants, distance between assembly plant and market, and number of key supplier sites. Two of these were identified through this research, i.e. the number of capable plants and number of key supplier sites. The authors make a distinction between component and assembly plants, which adds detail to the understanding of the impact of product architecture on global operations. In addition, they develop five propositions that can be tested in further survey research.

This study is restricted to three large manufacturing companies with global operations. However, the authors investigated both integral and modular products at these three companies and their associated global operations network. Still, further case or survey research involving a broader set of companies is warranted.

The key aspects for integral products are to have many key technologies in-house, concentration of production at a few capable plants, and economies-of-scale at assembly plants, while long distances between assembly plants and markets as well as few key supplier sites are acceptable. For modular products, the key aspects are many capable plants, economies-of-scope at assembly plants, short distance between assembly plants and markets, and many key supplier sites, while key technologies do not necessarily have to reside in-house – these can be accessed via key suppliers.

This paper is, to the authors’ knowledge, the first study on the explicit impact of product architecture on global operations networks, especially considering the internal manufacturing network.

The purpose of this paper is to describe the design for manufacture (DFM) and design for assembly (DFA) concepts and illustrate their benefits and applications.

Following an introduction, this paper provides an historical background to DFM and DFA. It then describes these techniques, highlights their capabilities and benefits and provides some examples of their applications. Finally, brief conclusions are drawn.

Software implementations of DFM and DFA are shown to yield significant financial savings by allowing products to be designed with enhanced manufacturing and assembly characteristics.

The paper provides an introduction to the DFM and DFA concepts which play a critical role in today's highly competitive markets.