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This paper aims to present a design methodology to enable product design for ease of assembly. It is corroborated by means of a case study. The methodology is based on standard time data. This enables quick computation of assembly time as well as comparing different design options for ease of assembly.

Component design that is easy to assemble is likely to take less time and vice versa. Assembly time is a function of product design attributes such as geometric shape, weight, center of gravity, type of material, number of fasteners and types of fasteners. The methodology uses standard data to achieve its objective. Numeric scores are developed for each design feature based on the aforementioned design attributes. This enables not only computation of assembly time for a brand new product but also comparison of two or more alternative design configurations from the point of view of ease of assembly.

The value of the system is corroborated by means of case studies of actual product designs. It is demonstrated that changing any of the underlying design attributes (such as type of fastener used, number of fasteners used, material of the component and component shape) is likely to result in changing the amount of time taken to assemble the product. The scoring system facilitates the quick computation of assembly time

The amount of time to assemble a product before the product is ever designed is facilitated by this system. Assembly time is a direct function of product design attributes. Process time is calculated using standard data, specifically, the Methods Time Measurement (MTM) system. This is accomplished by converting design features into time measurement units (TMUs). Assembly cost can then be easily computed by using assembly time as the basis. The computation of assembly time and cost is important inasmuch as its role in influencing productivity. This is of obvious value not only to the designer but the company as a whole.

A survey of papers and design‐for‐assembly systems shows where this discipline should be heading.

In this issue design‐for‐assembly is highlighted. Methods of designing parts to ease assembly, whether manual or automatic, have been around for 30 years. Brian Rooks thinks that some innovations in this area are now required and suggests computer graphics as a possibility.

Describes the redesign of the Clupicker, a ply separation device used in the textile industry, based on design for assembly techniques. Presents design for assembly (DFA) guidelines. Describes Boothroyd's Systematic DFA Methodology and Zorowski's PDM program, and analyses the design of the Clupicker using both of these methods. Presents and analyses a proposed redesign of the Clupicker based on DFA techniques.

This paper overviews work on a computer based consultation system, which uses artificial intelligence principles, and has been designed to aid the non‐specialist engineering designer or production engineer in the domain of design for assembly.

Reduced part count is a powerful cost‐saving element of design‐for‐assembly systems. A method has been developed in which component function and relationship data are used to present advice to the designer.

The key to rationalisation of the assembly process is not to be found in the area of production preparation, but in the area of design. The principles of design for assembly are described in detail.

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.

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.

The paper finds that the approach and the systems can reduce manufacturing costs and lead times.

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.

The system can estimate assembly time and cost for manual or automatic assembly and select a suitable assembly technique.

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.

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.

Design for assembly (DFA) techniques have been well established as a useful and powerful tool in the development of new products or the enhancement of existing products through redesign. With the ultimate goal of developing a quality product at the lowest possible cost, DFA teams are acutely aware of the need to eliminate unnecessary parts and refine geometrical considerations to aid in the product's assembly.