大型工件加工工艺流程虚拟规划系统

大型工件是重型装备设计和制造的基本单元,在加工过程中具有设备投资额高、占地面积大、加工工艺调整复杂的特点。构建工件加工生产线的物理模型和运动模型,根据需求调整生产线布局,预览规划结果,确定最优规划方案。     

Computer-aided manufacturing planning for mass customization: part 1, framework

This paper introduces a comprehensive system for the production planning of the mass customization of non-rotational parts. Combined features are defined based on the concept of part families. The process parameters are associated with the feature parameters so that rapid production planning can be achieved for product design changes. Setup planning is carried out based on both the best practice knowledge in industry and the algorithmic generation of setups. Manufacturing resource, fixture design, and tolerance issues are considered in the production planning. The system also estimates cycle times and generates standard documentation.     

面向绿色制造的工艺规划支持系统及应用

针对绿色制造研究中缺乏明显改善环境友好性的实用方法和工具的问题,开发了一种面向绿色制造的工艺规划支持系统。该系统主要由工艺要素选择、工艺过程优化和工艺方案绿色性评价3个功能模块,以及相应的模型库组成。支撑数据库主要提供各种绿色特性数据,包括工艺绿色特性数据库、工艺清单数据库、机床数据库、刀具数据库和切削液数据库等。在数据库和模型库的支持下,对工艺过程中的原材料消耗、辅助原材料消耗、能量消耗和环境排放物等进行优化和评价,从而辅助工艺人员优化和改善产品和零件制造过程的绿色性。通过某机床厂齿轮工艺过程的规划实例,验证了该系统的可行性。     

基于Multi-Agent的虚拟制造技术研究

虚拟制造技术是面向二十一世纪提高企业竞争力的有力手段。这里介绍了虚拟制造技术的基本概念、特点及体系结构;提出了基于Multi-Agent的分布式虚拟制造技术的集成环境;探讨了其组织方式及运行机制。     

Web-based distributed manufacturing control systems

With the evolution of the application of web technology, agent-based manufacturing systems can be both easily implemented and become a potential approach for modern manufacturing enterprises. In this paper, we present problems and models required for the development of web-based distributed manufacturing control systems. The specific objectives are: (1) to propose an appropriate architecture for a web-based distributed manufacturing control system, (2) to define the specification of a web-based cell controller, (3) to design the co-operative mechanisms, contract net protocol, for better system performance, (4) to upgrade the communication capability of existing CNC machines from RS232C to TCP/IP (Transmission Control Protocol/Internet Protocol) based on Ethernet .To demonstrate the proposed development, prototype software based on ASP and VB programming was designed and implemented. As a result, not only is a great amount of time saved in the development of web-based manufacturing control software, but this development can also enhance the competitive capability of companies trying to operate on a flexible basis.     

Function modules demanded for production control in distributed manufacturing system

This paper deals with the function modules demanded for production control in a distributed cellular manufacturing system. Cells are the distributed components of any manufacturing system. A proposed multipassing distributed simulating scheduling system (MPDSSS) deals with the production control functions regarding process planning (working-cell selection), scheduling, rescheduling, and real-time dispatching. The process planning function aims at selecting a good route for each job. The multipassing scheduling aims at providing a scheduling bidding strategy in a distributed fashion. The rescheduling aims at dealing with the large-effort change of the system with updating the precedence schedule to run in a new manufacturing period. The real-time scheduling deals with the small-effort change of the system with a real-time dispatching rule. All the production controlling functions have been implemented in distributed fashions. A simulation experiment demonstrates that the proposed MPDSSS leads to good results in the following criteria: minimum mean flow time, minimum waiting time, maximum machine utilisation, and minimum imbalance of cell utilisation.Nomenclature {A} grouping set ofA _i - A _i function-identical set of celli - BC _i the weighted bidding cost for the operation in celli - {C} performance criteria set - C _i ith element of {C} - CU _{f avg} average cell utilisation inA _f - CU _{f max} maximum cell utilisation inA _f - CU _i average cell utilisation of celli - CU_max maximum CU _i - CU_min minimum CU _i - {D} dispatching rule base - D _i ith rule in {D} - EFT earliest finishing time - EFT_max maximum EFT - ICU _f the imbalance of cell utilisation inA _f - P _m previously actual system performance for criterionC _m - RC _i rescheduling cost when using ruleD _i - SC _i improvement rate for system cost using ruleD _i - SP _a actual system performance - SP _m preceding simulation performance of theC _m with ruleD _i - SP _p ideally predictable system performance - SPD _a actual system performance deviation - TICU _i total imbalance of cell utilisation using ruleD _i - W weighting factor     

面向绿色制造的滚切加工工艺规划中的决策问题研究

在对滚切加工的T（加工时间）、Q（加工质量）、C（加工成本）、R（资源消耗）、E（环境影响）五个绿色制造目标特性分析的基础上,对面向绿色制造的滚切加工中的决策问题进行了研究,并某企业滚切加工中的滚齿机设备选择问题进行了案例分析。     

快速制造网格中全局工艺规划模块的分析与建立

基于快速制造网格平台,分析和建立了全局工艺规划模块,开发了全局工艺规划的分析工具包。该模块可以完成各种加工任务的全局工艺规划分析,确定每个任务的类别和全局工艺流程,实现任务分析的模块化。结合快速制造网格的应用实例发现,在实际运用中,全局工艺规划模块完全能够满足全局工艺规划分析的要求,对全局工艺规划决策具有重要的指导意义,验证了该模块的合理性与可行性。     

面向网络化制造的工艺分工规划技术研究

为了解决动态企业联盟的产品工艺分工自动规划问题,针对其制造资源配置的特点,提出了一种先设计逻辑工艺路线,通过逻辑制造单元一物理制造单元映射生成可执行工艺路线,再经过资源评估和优化配置生成工艺分工路线的新方法。在这3个主要过程中,逻辑工艺路线设计是影响工艺分工自动规划的关键,为此,采用了基于知识的方法实现智能化决策,避免了在工艺路线设计时必须考虑数量庞大的复杂资源配置这一难题,简化了工艺分工规划过程,容易实现自动化。     

基于制造资源能力的装夹工艺分层设计技术

为发展创成式的计算机辅助工艺设计,研究了计算机辅助工艺设计系统中工件装夹规划的自动生成算法.基于扩展有向图,建立了零件的公差信息和基准-加工特征关系的数学表示模型,基于公差分析和制造资源能力模型,建立了从单件层到多件层的工件装夹工艺生产算法.该数学模型和算法可自动识别工件的加工特征、装夹基准,并根据制造资源能力和公差分析对装夹进行优化分组,实现装夹分组对工件加工精度的影响最小化,进而生成装夹规程.最后以实例证明了该方法的可行性.     

A specification language for planning and fault recovery in manufacturing systems

This paper presents the syntax and semantics of a component-oriented rule-based language for specifying the formal models of manufacturing systems. A model captures the state of a component of the system in a set of first-order logic predicates, and it captures the semantics of the operations performed by this component in a set of rules that determine the preconditions and postconditions of an operation. The models are then used to plan the sequence of operations of each class of jobs to be manufactured by these systems. A plan-oriented fault detection and correction strategy is proposed. This strategy can automatically handle any combination of faults that may occur when monitoring the operations of manufacturing systems. A fault-tree is consulted prior to executing the scheduled operations of a plan, and the faults that affect the execution of these operations are handled subsequently. Resuming the original cyclic schedule is attempted, whenever feasible. As a proof of concept, a prototype implementation of both the main constructs of the component-oriented rule-based language and the planning and fault-recovery algorithms presented in this paper have been completed. This prototype is implemented on a Unix-based system in the Ada programming language. The specification of a manufacturing system is first expressed in the proposed language. These statements are then translated into Ada code. This code is next compiled by a Verdix Ada compiler and is executed in order to create and populate the model data structure of the system. A detailed plan of execution and a set of fault-recovery plans may then be derived for a job to be manufactured on this system.     

以制造BOM为核心的制造工艺数据管理研究

制造BOM可显示产品制造的阶层关系、工艺路线、工艺装备、材料等,是离散型制造企业重要的基础和生产数据。对于制造企业信息化而言,建立以制造BOM为核心的产品数据流是一项核心工作。本文基于对产品生命周期各阶段BOM的研究,分析了制造BOM的内涵、结构,提出以制造BOM为核心的制造工艺数据管理,并面向制造企业数据管理的需求,对以制造工艺数据为基础的制造数据管理进行了论述。     

虚拟制造关键技术的研究综述(上)

从制造系统建模、产品开发和制造过程仿真以及可制造性评价等几个方面,对虚拟制造关键技术的研究现状、存在问题和研究方向等进行了综述和评议。     

A framework for capacity planning and machine configuration in flexible assembly systems

We consider the problem of simultaneously determining the number of machines (and/or workers), the assignment of tasks (and related tools and components) to these machines, and the number of jobs circulating in a flexible assembly system (FAS), to satisfy steady-state throughput requirements for a family of similar products at minimum cost. We focus on situations where there are precedence relations among the various tasks, as is common in assembly systems. We present a framework for solving this problem based on a heuristic decomposition approach which involves the solution of only a few types of sub-problems. We demonstrate the efficiency and effectiveness of the overall procedure using a number of example problems.     

混合生产中作业计划体系研究

对于兼有离散和连续生产特征的混合生产行业,由于其计划体系的复杂性和多样性,尚未形成成熟的具有通用意义的应用方案。分析了混合生产的特征和混合生产计划体系的特点,提出了研究混合生产计划体系的思路,构建了该作业计划体系框架并描述了功能要求及信息联系,研究了前连续后离散这种混合生产模式的作业计划排程问题的离散制造与连续制造分解逻辑,并以毛纺织行业为背景,进行了连续生产环节计划排程优化算法研究,探讨了毛纺织混合生产计划体系对物料清单、工艺路线等基础数据管理的增强要求。     

Resource-requirements planning in flexible manufacturing systems

In this paper, we address the problem of planning the requirements of some of the important resources in flexible manufacturing systems. Specifically, we model the problem of estimating the required numbers and types of machines and tools in the context of a cellular layout. A two-stage procedure is developed which first forms the part families, using the complete-linkage clustering method based on a new similarity index defined in terms of the tooling requirements, and then subsequently estimates the resource requirements to manufacture the part families using an integer programming model. Several variations of the model are discussed and a numerical example is given.     

Rule-based production planning in flexible manufacturing systems

Production planning in flexible manufacturing may require the solution of a large-scale discrete-event dynamic stochastic optimization problem, due to the complexity of the system to be optimized, and to the occurrence of discrete events (new orders and hard failures). The production planning problem is here approached for a multistage multipart-type manufacturing shop, where each work cell can share its processing time among the different types of parts. The solution of this problem is obtained by an open-loop-feedback control strategy, updated each time a new event occurs. At each event time, two coupled problems are solved: 1) a product-order scheduling problem, conditioned on estimated values of the production capacities of all component work cells; and 2) a production-capacity planning problem, conditioned on predefined sequences of the product orders to be processed. In particular, the article aims at defining a production planning procedure that integrates both analytical tools, derived from mathematical programming, and knowledge-based rules, coming from experience. The objective is to formulate a hybrid (knowledge-based/analytical) planning architecture, and to analyze its use for multicell multipart-type manufacturing systems.     

面向绿色制造的滚切工艺规划决策问题研究

在对滚切加工的T(加工时间 )、Q(加工质量 )、C(加工成本 )、R(资源消耗 )、E(环境影响 )五个绿色制造目标特性分析的基础上 ,对面向绿色制造的滚切加工中的决策问题进行研究 ,并结合某企业滚切加工中的滚齿机设备选择问题进行案例分析     

分布式虚拟环境下的产品协同设计与制造

虚拟技术和计算机支持的协同工作（CSCW）技术已经渗透在设计与制造的活动中,并推动制造信息集成和网络协同设计与制造技术的发展。文中分析和讨论了分布式虚拟环境中的协同设计与制造系统的特点及其本要求,以五层结构形式给出了一处系统实现的框架模型。     

网络化制造系统功能规划标准化研究

目前,对网络化制造的通用术语、系统体系结构、功能目标和应用实施规范等尚未形成统一的标准和认识。为此,在分析标准化需求及制造系统建模方法的基础上,从功能视图角度给出了网络化制造系统的一种参考结构,进一步构建了网络化制造系统的功能体系结构模型,较为系统地描述了功能模型的主要内容。通过对网络化制造系统功能规划标准化进行探讨,为制定相应的标准提供了一定的参考。