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.     

Knowledge based process planning system for turned components

Recently, there has been a proliferation of CAD and NC systems for aiding the design and manufacture of components. However, CAD and CAM have not been fully integrated due to the difficulty in automating the intermediate function, process planning. At UMIST research is being carried out towards the integration of CAD and CAM by automating process planning. This paper describes the development of a process planning system for turned components using expert system techniques (EXCAP). This system has been integrated with the CAD system via IGES and with the NC machine using a cutting technology package developed at UMIST. Thus it is currently possible to generate NC programs automatically for relatively simple turned components by feeding in the CAD product data.     

制造工艺信息系统开发实施技术研究

制造工艺信息系统是制造企业工艺信息化的应用支撑系统。由于工艺设计与管理的复杂性,系统的开发与实施是一个渐进、动态的过程,为了保证系统的快速、深入应用,就需要建立系统开发实施标准、规范体系。本文在对制造工艺信息系统开发实施过程深入分析的基础上,以在CAPPFramework(863/CIMS支持的CAPP开发平台)上进行的实际开发实施工作为基础,论述了系统开发实施的关键问题,对系统开发实施的标准规范体系进行了深入研究。     

基于子链的云制造资源计划与协调机制研究

针对目前制造行业资源或能力过剩与不足并存的问题,为方便企业对制造资源的整合和对可用资源进行合理有效的计划与管理,对云制造、云子链的概念及结构模型、云子链的评价与构造过程、云子链产能计算方法进行了研究,提出了从子链角度对云制造服务平台上的制造资源或服务能力进行计划的方法;并从子链多向协作角度,对子链之间的计划协商、进度反馈、冲突化解的机制进行了研究,提出了各层次子链落实与协调云制造资源计划的方法。研究结果表明,云子链的应用能够实现更精确合理地核算和计划制造资源,各层次子链之间的协调机制为后续计划的实施提供了理论方向性指导,对云子链整体制造资源进行计划和协调具有可行性和先进性。     

基于C/S的CAPP工艺数据库技术研究

分析了CAPP系统中工艺数据的特点以及CAPP系统对数据管理的总体要求，研究了C1ient／Sever(C／S)处理模式在工艺数据库中的应用，构建了基于C／S体系的动态网络数据库系统，详细介绍了系统各模块的功能及系统的安全保障措施。     

Integrated assembly and machining planning for electronic products using a genetic algorithm approach

To produce an electronic product, both assembly operations and machining operations are required in the process plan. In most cases, the assembly operations and machining operations need to be combined in a continued order with an integrated sequence. This is different from the traditional process planning approaches in which machining operations and assembly operations are separated as two independent tasks with no interactions. For an electronic product, the two types of operations and the associated costs may affect each other in an interactive way. Therefore, the sequence planning of assembly operations and machining operations must be analyzed with an integrated model. In this research, a graph-based model is presented to represent the assembly and machining operations in an integrated model. The related operation cost functions are developed to evaluate the costs for the integrated assembly and machining sequences. The integrated sequence planning problem is solved using a genetic algorithm approach with an objective of lowest operation costs. As a result, the assembly operations and machining operations can be planned in an integrated sequence suitable for producing electronic products. The result shows that the developed method using the genetic algorithm approach is efficient for solving the integrated sequence planning problem. Example products are demonstrated and discussed.     

A multiobjective genetic algorithm for scheduling a flexible manufacturing system

Though the designers of Flexible Manufacturing Systems (FMS) strive to ensure the maximum flexibility in the system, in practice, after the implementation of such systems the operational executives often find it hard to accommodate frequent variations in the part designs of incoming jobs. This difficulty can very well be overcome by scheduling the variety of incoming parts into the system efficiently. In this work an appropriate scheduling mechanism is designed to generate a nearer-to-optimum schedule using Genetic Algorithm (GA) with two different GA Coding Schemes. Two contradictory objectives of the system were achieved simultaneously by the scheduling mechanism. The results are compared with those obtained by different scheduling rules and conclusions are presented.     

Concurrent process tolerance design based on minimum product manufacturing cost and quality loss

In a concurrent design environment, a robust optimum method is presented to directly determine the process tolerances from multiple correlated critical tolerances in an assembly. With given distributions of multiple critical assembly dimensions, the Taguchi quadric quality loss function is first derived. The quality loss is then expressed as the function of pertinent process tolerances. A nonlinear optimal model is established to minimize the summation of manufacturing costs and product quality loss. An example illustrates the proposed model and the solution method .     

大型零部件的复杂工艺并行设计方法的研究

针对大型机械零部件的工艺要求,提出了一种基于任务驱动、面向大型零部件制造的复杂工艺并行设计方法.在分析了大型零部件制造工艺特点的基础上,采用面向对象和特征技术的哲理,按照其所涉及的工艺类型和工序复杂程度进行分类和任务划分,建立工序特征库.在实际应用时,先依据具体零件的工艺特点和所包含的工艺种类,利用工艺特征库构造面向任务管理的工艺特征模型,并以此进行任务划分和分派.就复杂的工艺方案而言,可按照工艺特征,将其分解成一系列单独的子任务.在工艺设计过程中,通过对这些子任务的管理和监控实现并行工艺设计.采用这种新的工艺设计模式,使这些含有不同类型工序(如机加工、焊接、冲压、清洗和数控等)的复杂工艺设计任务实现了统一管理,提高了工艺设计灵活性和效率.     

飞机制造工艺路线分工计划及BOM管理系统研究

论述了在飞机制造企业中制造工艺数据信息的生成，转化，流动与管理，综合采用先进的计算机软件技术提出应采用基于web的计算模式，以EBOM和MBOM的形式完成对工艺数据信息的管理，并论述了MBOM的核心的地位以及SSPPD方式实现对MBOM数据的集成与共享。     

基于协同优化的工艺设计与调度并行集成

分析了现有工艺设计与生产调度的集成方式,包括柔性工艺设计、动态工艺设计、基于仿真的工艺设计、及并行工艺设计,讨论了各集成方式的优缺点,在此基础之上提出了基于协同优化的工艺设计与生产调度并行集成模型,并讨论了该模型的核心技术,即基于免疫遗传算法的工艺及调度方案协同优化.     

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     

船体装配计算机辅助工艺计划系统

介绍了某造船厂船体装配计算机辅助工艺计划系统。包括:BOM表和焊接信息的获取,工艺计划(包括工时定额、材料定额)的制订,工艺项目表制订,基于成本的工艺计划优化,工艺计划系统与管理软件的信息集成。系统采用PowerBuilder 6.0和SQL Server6.5编制。     

基于Web的工艺数据管理系统研究与开发

结合工艺数据管理系统开发 ,介绍基于JSP的Web应用系统开发模式 ,并介绍基于Web的工艺数据信息的生成、转化、流动与管理功能     

基于遗传算法的柔性制造系统机床选择问题研究

由于激烈的市场竞争环境,灵活的制造商应该以最快的速度向市场推出产品,以最少的成本进行生产,从而拥有使消费者满意的巨大能力.而具有快速时间响应和高度柔性的制造系统是必要的.在假设的条件下,构建基于零件加工时间和成本加权和为目标的柔性制造系统机床选择数学模型,在模型中考虑机床的维修成本.用C语言实现遗传算法在柔性制造系统机床选择中的应用,并与以前的例子进行比较.最后通过实验对遗传算法的参数进行分析.     

基于遗传算法的装配序列规划研究

分析了传统装配序列规划的不足,建立了考虑子装配体稳定性的目标函数,采用带记忆的遗传算法进行装配序列规划;在初始种群生成时,可以输入带专家知识的可行装配序列改善种群的组成成份;在各种群的生成过程中,始终保留所获得的当前最优可行装配序列,确保算法最终收敛到最优或近优解。最后以实例说明该方法的有效性。     

制造环境中AGV运输子系统的路径规划

阐述了制造环境中AGV运输子系统的路径规划方法,运用Dijkstra算法和A*算法都能求得最优解,但从计算量及速度来说,A*算法优于Dijkstra算法。     

QFD based optimal process quality planning

Process quality planning is an important activity of quality assurance. It aims to determine manufacturing processes with appropriate process capability to produce product characteristics. Quality function deployment (QFD) is a powerful tool for quality planning, which starts with identifying customer needs and ends with determining process plans. However, most studies on quality planning by QFD are limited to the product planning stage. The approach to process quality planning through QFD has rarely been discussed. This paper adopts the optimal QFD model and further develops it for process quality planning. By incorporating an empirical capability function for process elements, a composite process capability index (CCp) is presented to reflect the overall process quality level. Constraints including technical feasibility, correlations among process elements, project budget and development time are considered. A case study of the numerical control (NC) machining process quality for a thin-walled complex window frame of airship is given to illustrate how the proposed model can be effectively applied by process quality team to determine the optimal target level of process elements concerning with resources utilization .     

基于成组技术的层次化绿色工艺设计研究

提出了面向绿色加工的层次化零件工艺设计策略,即分两阶段将环境因素溶入零件工艺设计过程的措施:特征级设计阶段和总体设计阶段。并通过对一个被加工组件的案例分析来说明特征的相互作用问题。     

基于SEFJ-PDM平台的工艺数据管理系统

介绍基于SEFJ -PDM的工艺数据管理系统 ,在实现方便录入工艺数据的基础上 ,对工艺数据进行管理 ,生成各种生产用及管理用的工艺数据 ,并在SEFJ -PDM平台上与相关系统集成。