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The design for manufacturing and assembly (DFMA) is a family of methods belonging to the design for X (DfX) category which goal is to optimize the manufacturing and assembly phase of products. DFMA methods have been developed at the beginning of the 1980s and widely used in both academia and industries since then. However, to the best of the authors' knowledge, no systematic literature reviews or mapping has been proposed yet in the field of mechanical design. The goal of this paper is to provide a systematic review of DFMA methods applied to mechanical and electro-mechanical products with the aim to collect, analyse, and summarize the knowledge acquired until today and identify future research areas. The paper provides an overview of the DFMA topic in the last four decades (i.e., from 1980 to 2021) emphasizing operational perspectives such as the design phase in which methods are used, the type of products analysed, the adoption of quantitative or qualitative metrics, the tool adopted for the assessment, and the technologies involved. As a result, the paper addresses several aspects associated with the DFMA and different outcomes retrieved by the literature review have been highlighted. The first one concerns the fact that most of the DFMA methods have been used to analyse simple products made of few components (i.e., easy to manage with a short lead-time). Another important result is the lack of valuable DFMA methods applicable at early design phases (i.e., conceptual design) when information is not detailed and presents more qualitative than quantitative data. Both results lead to the evidence that the definition of a general DFMA method and metric adaptable for every type of product and/or design phase is a challenging goal that presents several issues. Finally, a bibliographic map was developed as a suitable tool to visualize results and identify future research trends on this topic. From the bibliometric analysis, it has been shown that the overall interest in DFMA methodologies decreased in the last decade. [ABSTRACT FROM AUTHOR]

In recent years, remanufacturing has received increased attention as a sustainable and profitable product recovery strategy. To facilitate the remanufacturing of used product returns, factors which affect remanufacturability should be considered during the product design stage. The selection of fastening method during the product design stage is one of the critical decisions which affects the remanufacturability as well as the total cost of disassembly and re-assembly of used products. Hence, both product assembly and disassembly issues should be considered in the product design stage for the selection of fastening methods. Simultaneous consideration of product assembly and disassembly in the product design stage for the fastening method selection has not been properly addressed in previous studies. In this paper, a methodology for selecting appropriate fastening method from a remanufacturing perspective is proposed in which both product assembly and disassembly are addressed. In the proposed methodology, an optimization model is formulated with the objective of minimizing the total cost of product assembly and disassembly. The genetic algorithm is employed to solve the model. A case study on the selection of fastening method for a laptop computer is conducted to illustrate the proposed methodology and to evaluate its effectiveness. The effect of the degree of product disassembly and the demand size for remanufactured products on the total cost of product assembly and disassembly was also investigated. The results showed the proposed methodology provide significant cost savings in the total product assembly and disassembly cost. [ABSTRACT FROM AUTHOR]

Remote laser welding which has benefits for both productivity and energy saving is receiving increased attention for automotive assembly lines. Introducing this innovative equipment requires a redesign process for assembly elements, for example to substitute resist spot welding with remote laser welding. The mating surfaces related to the welding need to be updated as well, but this is complicated when the shape design includes manufacturing and assembly elements based on current practice which hide the design intent. The challenge is to establish guidelines with the design parameters of automotive door frames and the process parameters of the joining process in order to maintain the design intent. In order to maintain the original design intent of the process planner, the author proposes a propagation model for the production stage which is defined as the interplay between parameters and quantitative comparison. The process parameters of remote laser welding are applied to the flange of the door frame. Also, the shape of each flange is synchronised with the changes according to the result of a quantitative comparison of the productivity and eco-efficiency. A design guideline tool to redesign the flanges was developed inside a commercial CAD system to show the proposed concept. Five flanges of a car door were subjected to redesign for introducing 4-kw remote laser welding with considerations of eco-efficiency, process time and weight change. The tools are shown to illustrate how to maintain design intent in the redesign process, and the concept was realised in a commercial CAD system. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of assembly times for electrical connections and wire harnesses. The various types of electrical connection are described, together with the assembly of wires and wire harnesses. Comparisons are made of the times for the assembly operations associated with each type of connection, obtained from a variety of sources. From these comparisons, estimates are made of average or recommended assembly times. Finally, the recommended times are presented in the form of classification schemes for use by designers during the early stages of design. [ABSTRACT FROM AUTHOR]

This paper reviews the relevant literature of the development of methodologies and systems for integrated intelligent design of assembled products and processes. Based on a combination of the concurrent engineering approach and artificial intelligence techniques, an assembly oriented intelligent scheme for the integration of design and planning is proposed, in which the following components or activities are considered and carried out concurrently and intelligently: assembly modelling and design (conceptual design; preliminary design; detailed design), assembly process planning, assembly system layout and design, assembly simulation, econo-technical (e.g. assembl-ability, assembly time and cost) and ergonomic analysis and evaluation. The literature is reviewed and discussed in relation to the methodologies and systems of implementing the above components or activities and an integrated environment to support them. In addition, some research of our group on this topic is introduced. [ABSTRACT FROM AUTHOR]

An integrated concurrent engineering methodology for developing a baby carriage is proposed. The development process is divided into three stages for considering the design, manufacture, and assembly problems. The product is first designed based on design criteria to ensure the best matching of needs and requirements. Then the parts and machine tools are coded using group technology (GT). The machine groups and the parts to be processed are given in matrix form using the production flow analysis (PFA) method. The machine cells are arranged based on the balance analysis of process time, and a flexible manufacturing system (FMS) is planned. Finally, the assembly line is planned based on the relationship of the parts. Some related parts are collected as a subassembly system. After the subassembly is decided, the work stations are arranged based on the required assembly time to obtain a high-performance assembly line. The results show that not only is the production cost of the product reduced, but also that the competitive properties are improved. This model can also be applied to develop other products. [ABSTRACT FROM AUTHOR]