Selection of materials using compromise ranking and outranking methods

Selection of proper materials for different components is one of the most challenging tasks in the design and development of products for diverse engineering applications. Materials play a crucial and important role during the entire design and manufacturing process. Wrong selection of material often leads to huge cost involvement and ultimately drives towards premature component or product failure. So the designers need to identify and select proper materials with specific functionalities in order to obtain the desired output with minimum cost involvement and specific applicability. This paper attempts to solve the materials selection problem using two most potential multi-criteria decision-making (MCDM) approaches and compares their relative performance for a given material selection application. The first MCDM approach is ‘Vlse Kriterijumska Optimizacija Kompromisno Resenje’ (VIKOR), a compromise ranking method and the other one is ‘ELimination and Et Choice Translating REality’ (ELECTRE), an outranking method. These two methods are used to rank the alternative materials, for which several requirements are considered simultaneously. Two examples are cited in order to demonstrate and validate the effectiveness and flexibility of these two MCDM approaches. In each example, a list of all the possible choices from the best to the worst suitable materials is obtained taking into account different material selection criteria. The rankings of the selected materials almost corroborate with those as obtained by the past researchers.     

Applications of utility concept and desirability function for materials selection

To satisfy the requirements of the manufacturing industries, material selection is considered as an important task. Wrongly chosen material may unnecessarily increase the product cost and lead to early failure of the product. While developing a product, the most suitable material is to be selected based on the requirements of the product and the available material properties. These material properties must match with the product requirements. To aid this material selection decision-making process, several mathematical tools and techniques have already been developed by the past researchers. Some of those techniques are computationally complex and their solution accuracy is often affected by the introduction of additional mathematical parameters. In this paper, two conceptually simple but strong mathematical techniques, i.e. utility concept and desirability function approaches are proposed to solve four material selection problems. These two methods are based on the quality characteristic values of the considered material alternatives for arriving at the satisfactory results. Almost a close match between the rankings of the alternatives obtained by these two methods and those derived by the past researchers confirms the suitability of both these approaches for solving material selection problems.     

Integrated and concurrent approach for compound sheet metal cutting and punching

In sheet metal processing and manufacturing, there are a lot of small- and medium-sized job shops. These small- and medium-sized manufacturing companies have been facing keen competitive pressure in the market. This pressure has forced these companies to make every effort to shorten product development lead-time, improve production efficiency, approach high-quality standards, but at the same time cut down the costs. To meet the needs of these companies, this paper presents a compound cutting and punching production method supported by an integrated CAD/CAPP/CAM system in sheet metal manufacturing. Many existing commercial CAD/CAM systems are not suitable for this manufacturing method, especially under concurrent and global design and manufacturing environments. Some problems have to be solved before these CAD/CAM systems can be employed and integrated for this compound manufacturing method. This paper deals mainly with the solutions to solve some of these problems. The solutions include an integrated data integration platform based on Pro/INTRALINK and STEP, and a knowledge-based real time CAPP (RTCAPP) system for compound sheet metal cutting and punching. Within the presented CAD/CAPP/CAM system, some key modules have been developed. They are the automatic tool selection and manufacturing sequencing module, a shortest tool path optimization module, a cost estimation module and an automatic insertion of auxiliary path module based on knowledge bases. These modules will be addressed here.     

A knowledge-based system for materials selection in mechanical engineering design

This paper studies various work on the development of computerized material selection system. The importance of knowledge-based system (KBS) in the context of concurrent engineering is explained. The study of KBS in material selection in an engineering design process is described. The development in materials databases, which sometimes serve as material selection packages, is also discussed. The use of KBS in material selection and the application in the domain of polymeric-based composite are chosen as typical examples.     

A module-based thermal design approach for distributed product development

Today, market demand for smaller, more powerful consumer electronics is rapidly posing a major challenge to product design. Several issues have been identified as major factors that affect the quality, cost, and delivery of product design in the so-called distributed design project. To address these concerns, a structured design method is needed. This paper proposes a design framework that can moderate inconsistent performance of system components (modules) resulting from a lack of communication between design sites. Module interconnection parameters at a system level are determined using the behavior-coupling matrix and work distribution matrix; initial design target values (ITVs) for system boundary conditions are provided for each module design. Our results show that system decomposition using ITVs offers a suitable framework for designing a product, considering the overall system behavior where each module is independently designed at different locations.     

Composites for automotive on-engine applications

Over the past fifteen years extensive developments have demonstrated the suitability of moulded reinforced polymer composites as replacements for cast and fabricated “bolt-on” engine components in mass produced vehicles and yet little has reached production. The article discusses some of the complex and interacting relationships between material selection, processing options, component design, investment and component costs which influence progress down the route to materials substitution. In a review of the progress already made, the problems resolved and those remaining, it is suggested that the next few years should see this work reach commercial fruition.     

Developing a fuzzy proportional–derivative controller optimization engine for engineering design optimization problems

In real world engineering design problems, decisions for design modifications are often based on engineering heuristics and knowledge. However, when solving an engineering design optimization problem using a numerical optimization algorithm, the engineering problem is basically viewed as purely mathematical. Design modifications in the iterative optimization process rely on numerical information. Engineering heuristics and knowledge are not utilized at all. In this article, the optimization process is analogous to a closed-loop control system, and a fuzzy proportional–derivative (PD) controller optimization engine is developed for engineering design optimization problems with monotonicity and implicit constraints. Monotonicity between design variables and the objective and constraint functions prevails in engineering design optimization problems. In this research, monotonicity of the design variables and activities of the constraints determined by the theory of monotonicity analysis are modelled in the fuzzy PD controller optimization engine using generic fuzzy rules. The designer only needs to define the initial values and move limits of the design variables to determine the parameters in the fuzzy PD controller optimization engine. In the optimization process using the fuzzy PD controller optimization engine, the function value of each constraint is evaluated once in each iteration. No sensitivity information is required. The fuzzy PD controller optimization engine appears to be robust in the various design examples tested.     

Determining steelmaking aim chemistry utilizing an iterative and knowledge-based approach

Development of knowledge-based systems for material design is a complex task, due to the interelationship of many factors in the steelmaking process. In addition, design specifications vary frequently and materials design knowledge is held in a largely intuitive undefined format. This paper discusses the first stage of a material design system which deals with the determination of the steelmaking aim chemistry. If an attempt is made to design aim chemistry based on the mathematical approach of utilizing the empirical models between various design parameters it would result in an unrealistic design because relationships between various design parameters are not always linear. Therefore applying the knowledge-based approach along with the mathematical approach to deal with this complex task is inevitable. The approach put forward in this paper is a hybrid one, where the knowledge base is applied at every stage of the design process to utilize expert as well as heuristic knowledge of metallurgists to obtain designs which are realistic and which take account of the various limitations and constraints encountered in steelmaking. The material design is also characterized by extensive utilization of the grade history database which contains performance data for various steel grades and thickness combinations. The inputs to the system are through interactive dialogue sessions and the basic inputs consist of the material standards, size, quantity, tonnage, end use and customers' special requirements. These basic inputs along with the numerous rules in the knowledge bases as well as mathematical modelling enable the effective design of steelmaking aim chemistry.     

The elicitation of knowledge from designers

This paper discusses elicitation of design knowledge from engineering design experts for the purpose of incorporation in knowledge-based systems. It is suggested that an understanding of the design activity can assist in the selection of suitable elicitation techniques. Design activity is briefly discussed. Following on from this, a number of knowledge elicitation techniques are reviewed including interviewing, questionnaires, attitude scaling, projective tests, repertory grid and observation of behaviour.     

A review of a smart condition monitoring and control system destined for harsh environments†

This paper describes the need for wireless piston telemetry together with elements of the design, development and operation of such a system. A specific feature of the system is the multiplicity of operating modes enabled by two‐way communication. The system has been demonstrated to work with thermocouples and accelerometers embedded in the piston of a very small engine at speeds of over 2000 rev min^−l. The piston‐mounted components can be fitted to a piston as small as 80 mm diameter, and size reductions are anticipated with improvements in implementation technologies. Typical results are quoted in the paper. Patents for this system are pending. Copyright © 2000 John Wiley & Sons, Ltd.     

Incorporation of high recyclability material selection in computer aided design

Manufacturing are now under increasing pressure of tighten environmental legislation to preserve natural resources. Product design, as a part of manufacturing activities, has to be more concern to deliver product specification with reduced environmental impact. Design for Recycling (DFR) is one of the promising approaches in prolonging material utilization of a product in the early stage of design. DFR focus on harmonizing product design with the recycling practices in order to minimize the loss of valuable materials and preventing unnecessary waste streams at the end of product’s life. In turn, it limits the usage of natural resources.To implement DFR, designers are faced with the challenge of compromising different design objectives such as cost, functional or technical requirements and product’s recyclability performance. This paper attempts to propose an intelligent approach that could facilitate designers to make an easy and quick recyclability assessment as well as selecting recyclable materials integrated with computer aided design. In this paper, the use of fuzzy inference system and genetic algorithm is proposed to optimize the multi-objective problem in the selection of recyclable materials. Case study on the actual conceptual design using computer aided design environment is demonstrated and showing that the proposed method successfully can be applied concurrently during product design. Comparison of proposed method with Sustainability Express Solid Work is also presented. The proposed method can assist product designers to design a high recyclability product without ignoring technical perspectives.     

Use of expert systems in the design of thermal equipment and processes

A study has been carried out on the use of knowledge-based computer-aided design methodology for the design of thermal systems. An expert system is developed using a Prolog-based front end, where the design rules, material databases, computational procedures, and the relevant expert knowledge are implemented. A combination of quantitative and heuristic inputs are employed in the design process. The basic approach employs an iterative redesign strategy, starting with an initial design obtained from the available knowledge base, and the design parameters are iteratively varied until the specified design rules and constraints are satisfied. The general approach can be employed for a variety of thermal systems. The application to a practical system is demonstrated by the design of an electrical furnace used in the thermal processing of materials. The results from the numerical simulation and design of this system are presented to indicate the basic features and the versatility of the expert system.     

论产品艺术没计创新的选材之道

分析了产品设计中材料选择的重要性和复杂性,并进一步探讨了产品设计的选材理论依据,在此基础上,研究在新材料和新工艺层出不穷的情况下,以系统的理论为指导,利用几个优秀产品设计的例子说明产品设计选材应当遵循的基本原则,归纳总结出产品艺术设计创新的"精、美、巧、奇、宜"选材之道。     

空调器外机环保包装结构设计及测试

目的为了达到保护产品的目的,探讨壁挂式空调外机产品包装用环保材料及创新结构设计。方法通过对产品进行包装测试,验证环保材料对产品的保护功能。通过运输、跌落、脚踩、堆码等产品包装测试试验,验证环保包装的选材及优化结构设计的可靠性。结果绿色产品包装的结构设计具有节约能源、资源,包装材料用量少,能循环回收利用,避免或减少废弃物产生,减少对环境产生的污染等特点。结论壁挂式空调可采用蜂窝材料、EVA材料、纸护角材料,以及瓦楞纸材料设计的创新结构,不仅适用于全自动化生产工艺流程作业,而且能更好地保护产品。     

Welding process selection for repairing nodular cast iron engine block by integrated fuzzy data envelopment analysis and TOPSIS approaches

The selection of welding process is one of the most significant decision making problems and it requires a wide range of information in accordance with the type of product. Hence, the automation of knowledge through a knowledge-based system will greatly enhance the decision-making process. A combined fuzzy data envelopment analysis (DEA) and TOPSIS is proposed to investigate the relative welding process selection factors and it can compare and evaluate different welding processes. The proposed approach compares each decision making unit (DMU) with the worst and the ideal virtual DMU and it ranks them via the relative closeness index. The proposed approach is used for ranking eleven welding processes which are commonly used for repairing nodular cast iron engine block in four cases and it is shown that the approach is sensitive to changes in dataset.     

A quality function deployment-based model for materials selection

Materials play a key role during the entire product design and manufacturing phase as a wrongly selected material may often lead to premature product failure causing loss of revenue and repute of the concerned manufacturing organization. While selecting the most suitable material for a specific application, the designers often need a sound and systematic methodology to deal with this problem having multiple candidate alternative choices and conflicting objectives. Most of the previously applied methodologies for material selection have either adopted criteria weights estimated using subjective judgments of the designers or failed to give due emphasis on the voice of the customers to meet their requirements. In this paper, a maiden venture is taken to solve the material selection problems using a quality function deployment (QFD)-based approach that can integrate the voice of the customers for a product with its technical requirements. The applicability and solution accuracy of this QFD-based material selection model is demonstrated with the help of four illustrative examples. To ease out the materials selection decision-making process, a user-friendly software prototype in Visual BASIC 6.0 is also developed.     

面向客户的产品规模定制设计及其应用

讨论产品设计过程中的基本模块，并提出规模定制设计的概念。面向客户的产品设计的核心是开发面向规模定制的产品族结构，实现与统一的产品开发和送货机制的后期集成。介绍了产品族结构的特点，以及明确产品族结构的步骤。同时给出了一个规模定制设计的研究实例。     

Selection Strategies for Materials and Processes

Designers employ a number of strategies in choosing material and processes. The choice can be based on engineering analysis, identifying candidates that best meet the mechanical, thermal, electrical and economic constraints of the design. It can be based on past experience, accessed through a questionnaire‐based selection engine. And it can be based on analogy, searching for materials that are “like” on or more other materials in particular regards – in color, or transparency, or texture for example. Here we explore the strategies, identifying ways in which they can be deployed.     

Implementation of knowledge-based system for iron core inductor design

We describe the implementation of a knowledge-based system for designing iron core inductors. We identify the underlying issues related to the implementation of such a system. We employ a recursive design methodology based on imitating an expert human designer that is suitable for embedding in the knowledge-based system. A hybrid knowledge base, using both frame-based and rule-based paradigms, together with assertions and procedural attachment, captures inductor-oriented design expertise. The paper establishes a general framework whereby dedicated knowledge-based systems for electromagnetic design can be built. It presents results that illustrate the performance of the developed system, particularly in comparison to the standard design procedure found in the literature.