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可重构制造系统理论研究 总被引:40,自引:3,他引:40
在已有定义基础上给出了可重构制造系统(RMS)的定义,分析了RMS与刚性制造系统(DMS)、柔性制造系统(FMS)的区别。建立了RMS的结构和组成、类别及理论体系,将RMS基础理论概括为系统随机建模、布局规划与优化、构件集成整合、构形原理、可诊断性测度和经济可承受性评估6个方面,并提出了RMS使能技术。 相似文献
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基于图论的可重构制造系统重构策略 总被引:3,自引:0,他引:3
可重构制造系统(RMS)是针对零件族设计的既具有定制的柔性,又具有高生产率的制造系统。RMS通过重构来适应市场需求的变化。RMS的设计目标是基于重构条件下寻求制造系统在全生产周期内的系统成本最优。首先建立RMS的各生产周期成本模型、重构成本模型与全生产周期成本模型,构建RMS在各生产周期的组态有向图,利用Dijkstra算法与双向扫视算法求得RMS在各生产周期的最优成本组态与K-1个次优成本组态。根据所求得各生产周期的最优成本组态与K-1个次优成本组态,重构成本模型与全生产周期成本模型,计算上下生产周期各组态间的重构成本,并构建RMS全生产周期的重构策略有向图,再次利用Dijkstra算法与双向扫视算法求得 RMS全生产周期的最优重构策略与K-1个次优重构策略。最后用实例验证了方法的有效性与可行性。 相似文献
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可重构制造系统多态可靠性建模与分析 总被引:1,自引:0,他引:1
针对利用传统方法建立多状态系统可靠性模型引起的组合爆炸问题,提出一种基于随机过程方法和改进的通用产生函数法(Universal generating function,UGF)的含中间缓冲区的可重构制造系统(Reconfigurable manufacturing system,RMS)多态可靠性建模方法。利用随机过程方法建立存在非相邻状态转移的可重构机床(Reconfigurable machine tool,RMT)的马尔科夫模型,求解机床各理论稳态概率;定义中间缓冲区状态,并通过分析中间缓冲区对机床可用度的影响,得到中间缓冲区可用度和机床各状态的实际稳态概率;结合RMS和RMT性能多态性的特点,对UGF进行改进。在此基础上,表示设备层和系统层的发生函数,建立多零件族可修RMS的多态可靠性模型,并对系统的各项性能指标进行分析。以双零件族四工序非串行缸盖机加工系统为例,验证该模型与分析方法的有效性。 相似文献
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首先介绍了可重构制造系统和公理化设计的基本概念,然后对可重构制造系统进行了二级分解,选取了其中非耦合情况下和准耦合情况下的案例,进行了可重构制造系统公理化设计,提出了X是算子的概念,并赋予了,新的概念。创新的利用公理化设计的方法对可重构制造系统进行相应的拆分与重组:根据市场需求,将整个制造系统拆分成具有部分功能组合的制造系统;将各个功能组合,组成整个制造系统。这对于提高制造系统的利用率,快速应对市场需求具有十分重要的意义。 相似文献
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提出了基于可重构制造单元的可重构制造系统集成设计框架.在该框架中,从规划和运行方面阐述了可重构制造系统的设计目标、设计流程及采用的关键技术,建立了支持可重构制造系统实施的计算机辅助设计系统的功能模型和体系结构,并讨论了系统的内部集成和外部集成问题.根据该设计框架,开发了集重构、布局规划、生产调度和仿真优化为一体的软件系统,该系统现已应用于航天、船舶和兵器部门. 相似文献
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A web-based advisory system for process and material selection in concurrent product design for a manufacturing environment 总被引:1,自引:1,他引:1
Xuan F. Zha 《The International Journal of Advanced Manufacturing Technology》2005,25(3-4):233-243
This paper reports the work of selecting suitable manufacturing processes and materials in concurrent design for manufacturing environment. In the paper, a fuzzy knowledge-based decision support method is proposed for multi-criteria decision-making in evaluating and selecting possible manufacturing process/material combinations in terms of the total production cost. Based on the proposed method, a prototype Web-based knowledge-intensive manufacturing consulting service system (WebMCSS) with the client-knowledge server architecture is developed to help designers/users find good processes and materials while still at the conceptual level of design. The system, as one of the important parts of an advanced design for manufacturing tool, is a concept level process and material selection tool that can be used as both a standalone application and a Java applet freely available via the Web. Interlinked with Web pages of tutorials, and reference pages explaining the facets, fabrication processes and material choices, the system performs reasoning and calculations using the process capability and material property data from the remote Web-based database and knowledge base that can be maintained and updated via the Internet. The use of the system is illustrated with an example. 相似文献
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Ahmed M. Deif Waguih ElMaraghy 《The International Journal of Advanced Manufacturing Technology》2007,32(5-6):557-562
Responsiveness to dynamic market changes in a cost-effective manner is becoming a key success factor for any manufacturing
system in today’s global economy. Reconfigurable manufacturing systems (RMSs) have been introduced to react quickly and effectively
to such competitive market demands through modular and scalable design of the manufacturing system on the system level, as
well as on the machine components’ level. This paper investigates how RMSs can manage their capacity scalability on the system
level in a cost-effective manner. An approach for modeling capacity scalability is proposed, which, unlike earlier approaches,
does not assume that the capacity scalability is simply a function of fixed increments of capacity units. Based on the model,
a computer tool that utilizes a genetic algorithm optimization technique is developed. The tool aids the systems’ designers
in deciding when to reconfigure the system in order to scale the capacity and by how much to scale it in order to meet the
market demand in a cost-effective way. The results showed that, in terms of cost, the optimal capacity scalability schedules
in an RMS are superior to both the exact demand capacity scalability approach and the approach of supplying all required capacity
at the beginning of the planning period, which is adopted by flexible manufacturing systems (FMSs). The results also suggest
that the cost-effective implementation of an RMS can be realized through decreasing the cost of reconfiguration of these new
systems. 相似文献
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关于在"产品设计"中必须引入最新技术的认知和举措 总被引:5,自引:0,他引:5
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。 相似文献
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Effect of reconfiguration costs on planning for capacity scalability in reconfigurable manufacturing systems 总被引:1,自引:1,他引:1
Ahmed M. Deif Waguih ElMaraghy 《International Journal of Flexible Manufacturing Systems》2006,18(3):225-238
In a globally competitive market for products, manufacturers are faced with an increasing need to improve their flexibility,
reliability, and responsiveness to meet the demands of their customers. Reconfigurable manufacturing systems (RMS) have become
an important manufacturing paradigm, because they broadly encompass the ability to react efficiently to this environment by
providing the exact capacity and functionality needed when needed. This paper studies how such new systems can manage their
capacity scalability planning in a cost effective manner. An approach for modeling capacity scalability planning is proposed.
The development of the model is based on set theory and the regeneration point theorem which is mapped to the reconfigurable
manufacturing paradigm as the capacity scalability points of that system. The cost function of the model incorporates both
the physical capacity cost based on capacity size and costs associated with the reconfiguration process which referred to
as the scalability penalty cost and scalability effort cost. A dynamic programming (DP) approach is manipulated for the development
of optimal capacity scalability plans. The effect of the reconfiguration costs on the capacity scalability planning horizon
and overall cost is investigated. The results showed the relation between deciding on the optimal capacity scalability planning
horizon and the different reconfiguration costs. Results also highlighted the fact that decreasing costs of reconfiguration
will lead to cost effective implementation of reconfigurable manufacturing systems. 相似文献
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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. 相似文献
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基于扩展随机Petri网的可重组制造系统建模与分析方法 总被引:5,自引:1,他引:4
可重组制造系统(Reconfigurable manufacturing system,RMS)可根据市场变化进行组态调整和组元升级,系统的建模与分析方法必须能适应上述特点。提出基于扩展随机Petri网(Extended stochastic Petri nets,ESPN)的模块化建模方法,将RMS不同的加工资源对应于相应的ESPN基本模块,并通过过渡变迁合成ESPN模型,该模型能适应任意分布的制造系统,可更加精确地反映生产过程。在此基础上采用基于行为表达式的分析方法,得到系统性能指标,该分析方法可不必画出可达图而直接得到系统性能关系函数,使分析过程更加直观、简洁。可重组电动机生产线的实例证明了该建模与分析方法的有效性。 相似文献
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An expert enhanced coloured fuzzy Petri net approach to reconfigurable manufacturing systems involving information delays 总被引:4,自引:1,他引:4
Rupesh Kumar Santosh Kumar M.K. Tiwari 《The International Journal of Advanced Manufacturing Technology》2005,26(7-8):922-933
In today’s competitive market, manufacturers need to quickly adapt to the changing demands of the customers. Reconfigurable
manufacturing system (RMS) is a cost-effective system that can easily absorb frequent changes in product demands. In this
article such a system is modelled using expert enhanced coloured fuzzy Petri net (EECFPN), which considers the demands of
customers as a fuzzy parameter and vividly captures the reconfigurability aspect of RMS. A fuzzy control strategy (FCS) is
proposed to deal with the information delays occurring during information transfer or decision implementation. After intensive
computational experimentation, it has been found that FCS outperforms the alternative priority (AP) heuristic and it is considered
an effective measure to deal with situations where considerable information delay is involved. 相似文献
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可重构制造系统工艺路线与系统布局设计研究 总被引:4,自引:0,他引:4
为使可重构制造系统的重构过程更加快速有效,提出了一种工艺路线和系统布局设计的方法.首先,基于图论构建了可重构制造系统工艺路线的有向网络模型,并采用Dijkstra算法和双向扫视算法,进行最优工艺路线和备选工艺路线的选择;然后,以工艺路线为基础,依据排队论中的相关理论,对制造系统的布局进行优化设计,以获得可重构制造系统布局方案.实例表明,该设计能够适应可重构制造系统快速多变的特征,提高对制造系统已有资源的利用率. 相似文献
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Assessment of manufacturing systems reconfiguration smoothness 总被引:1,自引:0,他引:1
Ayman M. A. Youssef Hoda A. ElMaraghy 《The International Journal of Advanced Manufacturing Technology》2006,30(1-2):174-193
The effect of the configuration selection on the smoothness and easiness of manufacturing systems reconfiguration process cannot be neglected, especially when dealing with reconfigurable manufacturing systems (RMS). The term “reconfiguration smoothness” is introduced in this paper to address this issue. In order to evaluate the level of reconfiguration smoothness (RS), a metric was developed to provide a relative measure of the expected cost, time, and effort required to convert from one configuration to another. This metric is composed of three components representing different levels of reconfiguration, namely; market-level reconfiguration smoothness (TRS), system-level reconfiguration smoothness (SRS), and machine-level reconfiguration smoothness (MRS). Rules are introduced to guide the development of execution plans for system-level reconfiguration, which we call “reconfiguration planning”. These plans help reduce the physical effort of reconfiguring the system. A case study is presented to demonstrate the use of the developed metric followed by sensitivity analysis to show the effect of changing different metric parameters. The results show how the developed metric provides a powerful relative assessment tool for the transitional smoothness between a current configuration and a number of candidate feasible configurations for the next period. This can affect the configuration selection decisions at the beginning of each configuration period. 相似文献
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21世纪由于制造材料、制造对象、制造手段、制造工艺和制造环境的根本变化,制造工业将随之发生重大的变革,因此人们提出了各种各样的制造模式来适应这种变革。本文介绍了可重构制造模式的突出优势、国内外的研究现状,并着重介绍了可重构生产系统(RMS)和可重构机床(RMT)的特点和基础的设计理论。 相似文献