An Efficient Heuristic Approach to Recognize the Infeasibility of a Loading Problem

The success of hierarchical production planning approaches for flexible manufacturing systems lies in the consistency of decision outcomes at various decision levels. For instance, the loading problem, which is solved at a lower level, may not yield a feasible loading solution to a set of part types selected at a higher level. This paper attemps to address the issue of recognizing the infeasibility of a loading solution. We present a modified loading model that includes a penalty for each operation not assigned to any machine. We develop a Lagrangian-based heuristic procedure and provide a sufficient condition on the quality of heuristic solutions that, if satisfied, will enable us to use the heuristic solutions to recognize the infeasibility of a loading problem. The proposed model and the dual-based heuristic can be effectively incorporated in an FMS hierarchical production planning approach that finds a good loading solution by iteratively comparing different part grouping scenarios.     

卧式加工中心FMS的装卸台站设计

FMS柔性制造单元工件的装夹是一大难点,通过对一种用于卧式加工中心FMS装卸台站结构的介绍,说明可以很好的解决这一难题.     

柔性制造系统中机器装载计划研究

研究了FMS生产环境下的机器装载问题。机器装载问题涉及将工件工序及其所需刀具合理地安排到加工机器上，在满足某些约束的前提下，使给定的性能指标得到优化。描述了问题的整数规划模型，同时提出了基于遗传算法的解决方案。最后以实例检验了算法的有效性，提出的方案能适用于较大规模的机器装载问题。     

A fuzzy based algorithm to solve the machine-loading problems of a FMS and its neuro fuzzy petri net model

This paper aims to develop a fuzzy-based solution approach to address a machine-loading problem of a flexible manufacturing system (FMS). The proposed solution methodology effectively deals with all the three main constituents of a machine loading problem, viz. job sequence determination, operation machine allocation and the reallocation of jobs. The main objectives of the FMS loading problem considered here are minimisation of system imbalance and maximisation of throughput; the constraints to be satisfied are the available machining time and tool slots. An analytical argument has been provided to support the membership function related to the operation machine allocation vector. Computational results revealed the superiority of the proposed algorithm over other heuristics when it is tested on a standard data set adopted from literature. A new class of petri net model called the Extended neuro fuzzy petri net is constructed to capture clearly the various details of the machine loading problem which can be further extended to learn from experience and perform inferences so that truly intelligent system characteristics can be realised.     

一种FMS中AGV的分层递阶控制系统

系统采用分层递阶的控制结构,实现了FMS中AGV的自动化控制。在介绍了系统组成和功能的基础上,阐述了其原理和实现。     

柔性制造系统(FMS)故障诊断技术研究综述

分析FMS的特点及其故障诊断的困难性。在综合大量文献的基础上,对国内外在该领域的主要研究内容、发展现状以及研究成果进行归纳和总结,指出当前研究工作的特点和已有研究存在的主要问题。对今后的发展进行了展望,指出集成诊断、多传感器信息融合、多方法综合应用的集成智能决策系统,以及网络化远程诊断服务是FMS诊断系统研究和发展的方向。     

FMS柔性的评价

本文对影响ＦＭＳ柔性的因素进行了较深入的分析，形成了因素层次关系，并提出用模糊评判的方法进行系统柔性评价的概念，构造了各因素对评语集合的隶属度函数，计算和评价过程简单，通过实例分析，证明是评价系统柔性的有效办法。     

混料托盘装载问题的建模

托盘装载问题属于NP－hard问题已被研究多年，针对机器人混合码垛的工程实践需要，提出了混料多盘装载问题的新概念，建立了该问题的混合整数规划模型，并给出了求解模型的启发式策略，运用算例检查了模型的有效性。     

OPC技术在FMS训练系统上的应用

结合南京航空航天大学机电学院FMS训练系统介绍了OPC技术，并洋细说明了OPC服务器及客户端接口的开发过程。     

提高柔性制造系统加工效率的措施

柔性制造系统日均使用折旧费较高,在同等生产条件下如何提高其加工效率,增加日产出,成了企业及技术人员所面临的一大课题.根据常用柔性制造系统的实际情况,从加工工艺、夹具、系统调试和维护四个方面提出了措施.     

柔性制造系统仿真教学模型的开发

设计柔性制造系统（FMS）仿真教学模型所考虑的主要原则应是使构成FMS的仿真模型贴近现代企业的生产实际。通过柔性制造系统的仿真教学模型的设计分析,介绍设计时所遇到的几个关键问题,说明柔性制造系统仿真教学模型的开发策略。     

面向FMS的计算机辅助工艺设计系统

介绍了一种以先进的柔性制造系统ＦＦＳ１５００－２为对象、针对墙板类零件的ＣＡＰＰ系统ＨＺＣＡＰ－ＡＰＴ总体结构，并提出一种描述零件信息的新方法。该系统以人机对话的方式输入零件的几何信息和工艺信息，由计算机自动生成零件的工艺文件和在ＦＦＳ１５００－２上加工的数控程序单。     

FMS的应用前景探讨

市场竞争和客户的个性化需求使现代的制造业中多品种,中、小批量生产所占的比重越来越大.柔性制造系统正是为适应这种新的市场环境而发展起来的.但进入20世纪90年代后,柔性制造系统的发展遇到一定困难,分析柔性制造系统在实施过程中存在的一些问题,并尝试找出相应的对策,以便使柔性制造系统焕发新的生机.     

基于刀具寿命约束的FMS刀具流死锁研究

刀具流死锁问题是柔性制造系统(FMS)调度中的重要核心内容,为实现合理的死锁回避,必须深入分析刀具流死锁的相关性质。在前期研究的基础上,分析了刀具寿命对刀具申请的影响,进一步建立了基于刀具寿命约束的刀具申请分配图,分析了死锁的相关性质,建立了在考虑刀具寿命的情况下的刀具流死锁判定定理,为下一步的深入分析死锁检测算法和死锁回避准备了基础。     

Performance Analysis of an FMS Operating Under Different Failure Rates and Maintenance Policies

Flexible manufacturing Systems (FMSs) typically operate at 70–80% utilization, which is much higher than the utilization of traditional machines that can operate with as low as 20% utilization. A result is that an FMS may incur four times more wear and tear than a traditional system. This requests the execution of effective maintenance plans on FMSs. While maintenance actions can reduce the effects of breakdowns due to wear-outs, random failures are still unavoidable. It is important to understand the implications of a given maintenance plan on an FMS before its implementation. This paper discusses a procedure that combines simulation and analytical models to analyze the effects of corrective, preventive, and opportunistic maintenance policies on the performance of an FMS. The FMS performance is measured by its operational availability index, which is determined using the production output rate of the FMS under a variety of time between failure distributions and different operational conditions. The effects of various maintenance policies on FMS performance are simulated and the results are compared to determine the best policy for a given system.     

基于Petri网模型的FMS控制决策方法研究

应用Petri网理论 ,通过对现有FMS(柔性制造系统 )进行分析和研究 ,确定了该FMS中的各状态和事件及其因果关系 ,建立了实际FMS的Petri网模型。通过该模型的描述和对FMS实际运行情况进行分析 ,建立了优化调度控制规则。依据模型和调度控制规则 ,构造了该FMS管理与控制软件 ,实现了用于一实际FMS的调度与控制决策系统和动态运行的有效控制     

多资源复合共用FMS的死锁研究

利用Ｐｅｔｒｉ网为资源复合共用ＦＭＳ进行建模,给出了关于此类系统死锁的一系列定义,讨论了系统死锁的充分必要条件。     

柔性制造系统设备故障诊断专家系统的开发研究

通过建立单元子知识库、行为子知识库和故障树子知识库,将复杂的故障信息进行有效分解,并利用知识库中的管理子系统管理各子知识库;采用正反推理混合方式以及单元推理、行为推理和故障树推理的方式,提高故障诊断效率。     

基于FMS技术模块化的机电一体化教学探讨

基于FMS技术的模块化机电一体化教学方法的探讨,有助于加深学生对机电一体化系统概念的理解,掌握柔性制造的内涵,把握未来制造业的方向,特别有助对学生培养学习的兴趣和专业技能的提高,培养机电一体化行业急需的复合型高级人才。     

Macro-capp: A prototype capp system for an FMS

This paper deals with the role, advantages, problems and solution techniques for the implementation of dynamic Computer Aided Process Planning (CAPP) systems in a Felxible Manufacturing system (FMS). A large variety of part features for both rotational and prismatic parts are considered. A custom group technology coding technique is designed and implemented to describe part profile to system software concisely and comprehensively. The part profile code is assimilated by the system interactively. A prototype CAPP system was designed for a pseudo FMS containing multiple machining centres. The system described develops process plans that consider both alternative routes and methods to manufacture a part. Heuristic knowledge was implemented to choose between alternatives with flowtime minimization as the objective function. The system was tested and its outputs validated with respect to both prismatic and rotational parts.