Reconfigurable manufacturing systems: Principles,design, and future trends

Reconfigurable manufacturing systems (RMSs), which possess the advantages of both dedicated serial lines and flexible manufacturing systems, were introduced in the mid-1990s to address the challenges initiated by globalization. The principal goal of an RMS is to enhance the responsiveness of manufacturing systems to unforeseen changes in product demand. RMSs are costeffective because they boost productivity, and increase the lifetime of the manufacturing system. Because of the many streams in which a product may be produced on an RMS, maintaining product precision in an RMS is a challenge. But the experience with RMS in the last 20 years indicates that product quality can be definitely maintained by inserting in-line inspection stations. In this paper, we formulate the design and operational principles for RMSs, and provide a state-of-the-art review of the design and operations methodologies of RMSs according to these principles. Finally, we propose future research directions, and deliberate on how recent intelligent manufacturing technologies may advance the design and operations of RMSs.     

飞机制造质量保证技术研究

针对当前飞机制造企业信息系统众多、质量信息数据来源不一致、对贯穿飞机研制全生命周期的产品三维数模缺乏相应的质量控制与保证技术等问题,通过分析飞机研制质量形成过程,研究了产品设计、工艺设计、工装准备、生产制造和检验检测各阶段质量保证手段,在此基础上提出飞机制造质量管控框架系统,并对产品模型质量检查和质量数据采集技术进行了初步研究。     

Inspection Allocation Planning for a Multiple Quality Characteristic Advanced Manufacturing System

Producing products with multiple quality characteristics is always one of the concerns for an advanced manufacturing system. To assure product quality, finite automatic inspection systems should be used. Inspection planning to allocate inspection stations should then be performed to manage the limited inspection resource. Except for finite inspection station classes, in this work, the limited number of inspection stations, of each inspection station class, is considered for solving the inspection allocation problem in a multiple quality characteristic advanced manufacturing system. Since the product variety in batch production or job shop production increases to satisfy the changing requirements of the various customers, the tolerances specified will vary from time to time. This inspection allocation problem is solved using a unit cost model in which the manufacturing capability, inspection capability, and tolerance specified are concurrently considered for a multiple quality characteristic product. The situation of unbalanced tolerance design is also considered. The inspection allocation problem can then be solved according to customer requirements. Since determining the optimal inspection allocation plan seems to be impractical, as the problem size becomes large, two decision criteria (i.e. sequence order of workstation and tolerance interval) are employed separately to develop two different heuristic solution methods in this work. The performance of each method is measured in comparison with the enumeration method that generates the optimal solution. The result shows that a feasible inspection allocation plan can be determined efficiently. ID="A1"Correspondance and offprint requests to: Dr Yau-Ren Shiau, Department of Industrial Engineering, Feng-Chia University, 100 Wenhwa Road, Seatwen, PO Box 25–097, Taichung 407, Taiwan     

信息时代的全球制造策略--兼议我国制造业的发展

根据当前国际制造业的发展和因特网的广泛应用，论述发展全球制造的必然趋势，讨论全球制造企业发展的条件和方式，提出我国机械制造业应如何在竞争中求生存的建议，并着重阐述开发应用CAD系统、建立企业信息管理系统的重要性，以及提出在产品设计和制造过程中的创新是企业在市场竞争中取得成功和创建全球化制造企业的必要条件。     

制造系统中的公差与成本

公差设计是产品设计中的重要组成部分。公差设计的优劣,对产品制造加工过程有直接影响。文章详细分析了产品公差设计的类型和过程及产品成本的各项因素,提出了公差—成本关系的基本模型,为基于成本最低的公差设计优化提供了基础理论依据。     

CONCURRENT PRODUCT PORTFOLIO PLANNING AND MIXED PRODUCT ASSEMBLY LINE BALANCING

Reconfigurable products and manufacturing systems have enabled manufacturers to provide "cost effective" variety to the market. In spite of these new technologies, the expense of manufacturing makes it infeasible to supply all the possible variants to the market for some industries. Therefore, the determination of the right number of product variants to offer in the product portfolios becomes an important consideration. The product portfolio planning problem had been independently well studied from marketing and engineering perspectives. However, advantages can be gained from using a concurrent marketing and engineering approach. Concurrent product development strategies specifically for reconfigurable products and manufacturing systems can allow manufacturers to select best product portfolios from marketing, product design and manufacturing perspectives. A methodology for the concurrent design of a product portfolio and assembly system is presented. The objective of the concurrent product portfolio planning and assembly system design problem is to obtain the product variants that will make up the product portfolio such that oversupply of optional modules is minimized and the assembly line efficiency is maximized. Explicit design of the assembly system is obtained during the solution of the problem. It is assumed that the demand for optional modules and the assembly times for these modules are known a priori. A genetic algorithm is used in the solution of the problem. The basic premise of this methodology is that the selected product portfolio has a significant impact on the solution of the assembly line balancing problem. An example is used to validate this hypothesis. The example is then further developed to demonstrate how the methodology can be used to obtain the optimal product portfolio. This approach is intended for use by manufacturers during the early design stages of product family design.     

现代设计与知识获取

一个新产品的竞争能力在于产品设计中新知识的含量，在现代设计技术中，必地为开发一个新产品获取新设计知识的能力的发展给予更多的重视，本文讨论了设计知识的结构，获取设计知识的信息来源和处理技术，建议在信息科学，知识工程和计算机技术的基础上发展一个设计知识获取系统和并行设计环境以加速我国制造工业现代化的步伐。     

Design for pressure die casting—A DFM example

The designer makes many maufacturing decisions that influence the production cost and the quality of the product. It is therefore important to ensure that the designer has a good foundation for these decisions. When talking DFM, it is important to realise that there are large differences between companies in how product design and production are carried out. The objective of the present research is to investigate and to improve the communication flow between design and production for a selected area: pressure die casting. This area is characterised by many subcontracting producers, and design and production are therefore often placed at different geographic locations. This makes an efficient communication flow even more important and it also makes the communication interface more visible. This paper discusses how manufacturing considerations are made in different design situations and how information supporting tools should be formed accordingly. Results from an investigation of DFM in a number of pressure diecasting companies and companies that design products for pressure die casting are presented. The investigation focuses on the type, the detailing level and the accessibility of the part information passing from design to production and on the manufacturing guidelines and suggestions coming from production to design.     

DESIGN OF RECONFIGURABLE MANUFACTURING SYSTEMS WITH STRONGLY COUPLED NATURE

Today's manufacturing environment forces manufacturing companies to make as many product variations as possible at affordable costs within a short time. Mass customisation is one of most important technologies for companies to achieve their objectives. Efforts to mass customisation should be made on two aspects: ① To modularize products and make them as less differences as possible; ② To design manufacturing resources and make them provide as many processes variations as possible. This paper reports our recent work on aspect ②, i.e. how to design a reconfigurable manufacturing system (RMS) so that it can be competent to accomplish various processes optimally; Reconfigurable robot system (RRS) is taken as an example. RMS design involves architecture design and configuration design, and configuration design is further divided in design analysis and design synthesis. Axiomatic design theory (ADT) is applied to architecture design, the features and issues of RRS configuration design are discussed, automatic modelling method is developed for design analysis, and concurrent design methodology is presented for design synthesis.     

A model to build manufacturing process chains during embodiment design phases

The methods for manufacturing process selection from early design phases avoid later mistakes and ensure the success during product manufacturing. Currently, the majority of the products need more than one manufacturing process to become finished parts. This is known as a manufacturing processes chain, and it is important that this manufacturing chain is well designed. This paper presents the bases and the activity model (IDEF?) to develop a decision-support system that helps designers and manufacturing engineers to configure manufacturing process chains while the product is being designed. The model schematizes all the activities and information involved in obtaining reliable manufacturing process chains. The support system has been applied to an air-bending die design process to be used to perform either air-bending or bottoming.     

一起球罐险肇事故分析处理案例与讨论

介绍了某台1000 m3储氧球罐进出气阀对接法兰发生泄漏后险肇事故处理案例,分析了法兰开裂形成原因,对特种设备制造安装监检过程,严格按设计资料监检验收把关的重要性进行了讨论。     

Quick decision-making support for inspection allocation planning with rapidly changing customer requirements

Manufacturing products with multiple quality characteristics is always one of the main concerns for an advanced manufacturing system. To assure product quality, finite automatic inspection systems should be available and employed. Inspection planning to allocate inspection stations should then be performed to manage limited inspection resources. Since product variety in batch production or job shop production is increased to satisfy the changing requirements of various customers, the specified tolerance of each quality characteristic varies from time to time. Except for a finite inspection resource constraint, therefore, manufacturing capability, inspection capability, and tolerance specified by customer requirement are considered concurrently in this research. A unit cost model is constructed to represent the overall performance of an advanced manufacturing system. Both the internal and external costs of a multiple quality characteristic product are considered. The inspection allocation problem can then be solved to reflect customer requirements. Since determining the optimal inspection allocation plan seems to be impractical as the problem size gets larger, in this research, two decision criteria (i.e., sequence order of workstation and tolerance interval) are employed concurrently to develop a heuristic method. The performance of the heuristic method is measured in comparison with an enumeration method that generates the optimal solution. The result shows that a feasible inspection allocation plan to meet changing customer requirements can be determined efficiently.     

Concurrent process/inspection planning for a customized manufacturing system based on genetic algorithm

Producing products with multiple quality characteristics is always one of the concerns for an advanced manufacturing system. To assure product quality, finite manufacturing resources (i.e., process workstations and inspection stations) could be available and employed. The manufacturing resource allocation problem then occurs, therefore, process planning and inspection planning should be performed. Both of these are traditionally regarded as individual tasks and conducted separately. Actually, these two tasks are related. Greater performance of an advanced manufacturing system can be achieved if process planning and inspection planning can be performed concurrently to manage the limited manufacturing resources. Since the product variety in batch production or job-shop production will be increased for satisfying the changing requirements of various customers, the specified tolerance of each quality characteristic will vary from time to time. Except for finite manufacturing resource constraints, the manufacturing capability, inspection capability, and tolerance specified by customer requirement are also considered for a customized manufacturing system in this research. Then, the unit cost model is constructed to represent the overall performance of an advanced manufacturing system by considering both internal and external costs. Process planning and inspection planning can then be concurrently solved by practically reflecting the customer requirements. Since determining the optimal manufacturing resource allocation plan seems to be impractical as the problem size becomes quite large, in this research, genetic algorithm is successfully applied with the realistic unit cost embedded. The performance of genetic algorithm is measured in comparison with the enumeration method that generates the optimal solution. The result shows that a near-optimal manufacturing resource allocation plan can be determined efficiently for meeting the changing requirement of customers as the problem size becomes quite large.     

面向全球制造环境的先进制造使能技术

动态联盟企业的组织模式,联盟企业间的动态伙伴关系,动态联盟的群体决策支持系统,动态联盟的组织运行和经营管理技术是敏捷企业的主要研究内容,并行设计技术主要同向球制造网的产品并行设计技术,异地设计与制造技术主要研究异地设计环境下产吕数字化建模及数字化定义,分布式数字化装配技术,工装数字化设计及工装数字化装配技术,虚拟制造与制造过程仿真技术,支持异地设计与制造的计算机协同支持环境（CSCW）等,GM环境下的产品信息集成技术主要研究基于Internet技术的STEP信息集成,分布式产品数据管理技术,基于分布式对象体系的信息集成和全球制造环境网络支持平台,GM环境下的产品开发过程研究的主要研究对象包括产品开发过程建模及分析,仿真工具,产品开发过程管理等。     

科学发展观指导下的产品系统化设计的理论与方法

产品的研发和设计在企业的发展中起着十分重要的作用,在产品研发和设计过程中,采用先进的或理想的设计方法有助于提高产品的“先天性”优良品质。近百年来,国内外科技工作者已提出70多种产品设计方法。10多年来,在吸取这些设计理论和方法优点的基础上,提出一种在科学发展观指导下的产品系统化设计方法。该方法概括以下8方面的要点：① 原来的产品设计的原5项要素质量(Quality, Q)、成本(Cost, C)、生产周期(Time, T)、环境(Environment, E)和服务(Serve, S)应该用6项设计要素思想(Idea, I)、Q、C、T、E和S来代替,增加产品设计的正确指导思想I;② 用4个更具体的设计步骤,即3I(Investigation)调研、7D(Design)规划、1+3+X实施和3A(Assessment)检验来代替传统的产品设计步骤;③ 将产品的性能分为结构性能、使用性能和制造性能等三种主要性能;④ 提出绿色设计宜用和谐设计来取代,按线性系统的常规设计方法在一些特殊的情况下应该用深层次的设计方法来取代;⑤ 进一步说明顶层设计和系统化设计的概念和内涵;⑥ 对完整性与非完整性技术系统进行讨论;⑦ 写出产品设计目标、设计内容和设计方法的关联方程;⑧ 写出产品设计质量的理论表达式。上述设计方法已应用于多种产品的设计,均取得良好的效果。     

关于在"产品设计"中必须引入最新技术的认知和举措

着重讨论我国关于产品设计认知上的一些碰撞。争论的核心是“什么是设计？”。表面上看这个问题很简单,其实它包含深刻的历史、经济、文化和技术的背景。这里仅就技术方面的问题进行探讨。在经济全球化的今天。制造业的竞争实际上是产品设计的竞争。我国是一个制造大国,却不是一个制造强国,主要就是因为我们在产品设计方面处在缺乏竞争力的地位。而正是因为长期置身于竞争之外,很多企业界人士和工程师对于设计解决什么问题、设计竞争和竞争的焦点、竞争取胜的条件以及是否和如何能够形成这些条件,研究得很少。结果要么是认为照搬国外某些片断经验就可以解决问题,要么就是对参与竞争望而却步。这样就给技术准备带来很大的困难。因为对于如何准备没有统一的认知,使得有限的资源不能集中使用,既造成了浪费,又拖延了形成竞争力的时间。要组织尽可能多的人力物力来解决我国产品设计上的竞争力,统一认知是非常重要的。     

Tolerance chart balancing with a complete inspection plan taking account of manufacturing and quality costs

This paper introduces a mathematical model of tolerance chart balancing for machining process planning under complete inspection. The criteria considered in this study are based on the combined effects of manufacturing cost and quality loss, under constraints such as process capability limits, product design specifications, and product quality requirements. Manufacturing costs include the machining cost, part cost, inspection cost, reworking cost, and replacement cost. The machining cost is expressed in geometrical decreasing functions, which represent tolerances to be assigned. Process variability is expressed in quadratic loss functions, which represent the deviation between the part measurement and the target value. An example is presented to demonstrate the proposed model. A comparison made with previous methods shows that the proposed model minimizes the total cost of manufacturing activities and quality-related issues in machining process planning, particularly in the early stages. Moreover, the applications are not be limited to machining process planning but can also be used in other forms of production planning.     

CAD Model-Based Intelligent Inspection Planning for Coordinate Measuring Machines

As the market competition among enterprises grows intensively and the demand for high quality products increases rapidly, product quality inspection and control has become one of the most important issues of manufacturing, and improving the efficiency and accuracy of inspection is also one of problems which enterprises must solve. It is particularly important to establish rational inspection planning for parts before inspecting product quality correctly. The traditional inspection methods have been difficul...     

有机热载体炉产品制造监检浅谈

随着锅炉参数的不断提高,安全保障工作显得越来越重要,制造质量是安全保障的首要环节,通过产品监检,是提高产品的制造质量的一种有效途径。有机热载体炉监检过程中,虽然只有少部分制造要求与蒸汽锅炉有所区别,监检员在明白两者之间的区别后,能更好的保证有机热载体炉的监检品质,达到保障设备的安全使用的目的。     

A cost-tolerance analytical approach for design and manufacturing

Tolerance assignment in mechanical engineering product design and manufacturing is critical both for product quality and performance as well as for its manufacturing cost. Simple design rules, industry available comparative experimental data, tables, charts, and personal expertise are currently used for cost optimum tolerancing. Such a methodology is not very practical, requires considerable time and effort and is not always suitable for a CAD/CAM environment. To face these limitations, a new model for the manufacturing cost-tolerance function has been developed and is presented in the paper. It may well be used for direct-tolerance optimisation applications and it is shown that it produces results that are in satisfactory agreement with existing cost-tolerance data. Its use is further analysed and demonstrated in solving linear manufacturing tolerance transfer problems.