飞灰包装智能产线设计与虚拟调试

目的 设计一种全自动飞灰包装智能产线,旨在为某垃圾焚烧厂的飞灰包装产线的自动化改造项目提供可行性方案。方法 从飞灰包装的实际工艺需求出发,介绍产线总体设计和工位布局。针对吨袋开口装置和机器人专用手爪的设计与工作原理进行介绍。推导理论套袋力公式以指导专用手爪和出灰筒等机构的设计。在产线结构设计的基础上,为进一步验证该结构和布局是否能够无障碍地实现飞灰包装的所有工序流程,采用基于NX MCD和虚拟PLC的虚拟调试的方法,并结合PLC程序为整个包装产线进行工序流程仿真。结果 仿真显示该产线可以在PLC程序控制下全自动地、无障碍地实现飞灰包装的11个工序。产线的6个工位均可以实现无人运行。结论 可以通过添加开口装置与机器人等设备,改造原有半自动的包装产线,并为原产线解决了大型吨袋的自动开口、取袋、套袋的问题。     

Control logic verification for an automotive body assembly line using simulation

In this paper, an approach is proposed that verifies the controller logic processes for the automobile industry via simulation. For this purpose, a state-based object model that creates a virtual car body assembly line is proposed and a verification methodology using observed signal sequences during the simulation is proposed. This approach was applied to an assembly line controlled by a PLC and the effectiveness of the proposed system was explained in a case study.     

虚拟制造中仿真技术的应用

虚拟制造系统是现实制造系统在虚拟环境下的精确映射,是利用计算机模型仿真真实系统中的物理和逻辑活动。本文指出仿真是实现虚拟制造的主要手段。仿真在制造系统中的应用按照人的介入与否分为一般仿真层和虚拟现实层。分析了两层之间的联系与区别,列出了各层仿真的主要内容和可实现的程度;介绍了目前主要的虚拟制造仿真软件;最后,给出了三维动画表示的生产线虚拟仿真的一个实例。     

基于三次拟合方程畸变校正的光电测量系统

在大视场光电测量系统中,光学系统产生的畸变使目标在线阵CCD上的成像偏离了理论成像点,导致系统产生测量误差.为了减小该误差,提高系统的测量精度,根据畸变产生机理,设计了由11个等距目标点组成的畸变检测装置.根据检测得到的系统实际畸变变化情况,需要拟合出系统测量时目标点在线阵CCD上成像位置的补偿方程.以检测装置测量拟合得到的三次补偿方程作为畸变校正的数学模型编写了测量校正程序,对光电测量系统进行了实验检测.测量结果表明,当目标物物高为200.115mm时,按照拟合的补偿方程进行计算补偿,可将畸变误差从校正前的-2.08mm提高到校正后的0.05mm,并使系统整体检测精度从1.039%提高到0.025%.     

Analysis of the heat transfer and friction factor correlations influence in the prediction of evaporating flows inside tubes

A methodology for analysing the influence of the heat transfer and friction factor correlations in the prediction of the two-phase flows inside horizontal ducts under evaporation phenomena is presented. An experimental unit based on single stage vapor compression refrigerating system with two parallel evaporation devices has been built to work under real refrigeration conditions. The first evaporation device consists of a double pipe evaporator which allows determining the heat flux through the pipe. The second device is an electrically heated pipe evaporator with uniformly distributed temperature and pressure sensors along the fluid path. The experimental data of temperature and pressure distribution along the smooth heated duct is compared with a selected set of heat transfer and friction factor correlations through a detailed numerical evaporation model. The aim of this paper is to determine possible criteria to select the most suitable heat transfer and friction factor correlations available.     

虚拟联动仿真技术的实现与应用

为解决机械设备在研发设计完成时,必须借助实物 PLC 对设备的性能进行虚拟仿真验证,并且不能对PLC 程序的合理性进行检验等问题,提出了虚拟联动仿真的概念。 采用构建虚拟设备与虚拟 PLC 运行环境的方法,利用高级语言实时传递和处理虚拟 PLC 与虚拟设备之间的信号,并将运行情况和故障等信息在虚拟场景中表现出来,最终实现了不依赖实物 PLC 对机械设备的性能进行虚拟仿真验证,同时可以检验 PLC 程序的合理性,拓展了虚拟仿真的新思路。 以喷印机运动控制仿真为例,论述了虚拟联动仿真技术的必要性与可行性。     

基于GA–BP神经网络的汽车内饰板虚拟制造研究

目的 以某汽车内饰板为研究对象进行虚拟制造,以提前得到相对准确的工艺参数并减少成形缺陷的产生。方法 研究了工艺参数对产品拉延成形质量的影响,并确定了拉丁超立方抽样区间,在抽样区间内抽取60组样本数据,以最大减薄率为目标值,以前50组样本数据为测试集、后10组样本数据为预测集,使用基于GA–BP神经网络的遗传算法得到最优工艺参数,并将其代入有限元分析软件DYNAFORM中进行虚拟制造。结果 训练后GA–BP模型的预测值与期望值最大误差为0.299 7%,最大预测误差率为1.747 38%;遗传算法预测的最大减薄率为16.548%,虚拟制造得到的减薄率为16.167%,虚拟制造值与预测值的大小仅相差0.318%,仿真误差的误差率为2.36%。结论 虚拟制造结合先进算法的优化方法可以指导后续生产。     

Plant model generation for PLC simulation

This paper reports an automated procedure for constructing a plant model for PLC simulation. Since PLC programs contain only the control logic without information on the plant model, it is necessary to build the corresponding plant model to perform the simulation. Conventionally, a plant model for PLC simulation has been constructed manually, which requires much effort and in-depth knowledge of the simulation. As a remedy for this problem, we propose an automated procedure for generating a plant model from the symbol table of a PLC program. To do so, we propose a naming rule for PLC symbols so that the symbol names include sufficient information on the plant model. By analysing such symbol names, we extract a plant model automatically. The proposed methodology has been implemented and test runs performed.     

Development of an advanced human–machine interface for next generation nuclear power plants

An advanced human–machine interface (HMI) has been developed to enhance the safety and availability of a nuclear power plant (NPP) by improving operational reliability. The key elements of the proposed HMI are the large display panels which present synopsis of plant status and the compact, computer-based work stations for monitoring, control and protection functions. The work station consists of four consoles such as a dynamic alarm console (DAC), a system information console (SIC), a computerized operating-procedure console (COC), and a safety system information console (SSIC). The DAC provides clean alarm pictures, in which information overlapping is excluded and alarm impacts are discriminated, for quick situation awareness. The SIC supports a normal operation by offering all necessary system information and control functions over non-safety systems. In addition, it is closely linked to the other consoles in order to automatically display related system information according to situations of the DAC and the COC. The COC aids operators with proper operating procedures during normal plant startup and shutdown or after a plant trip, and it also reduces their physical/mental burden through soft automation. The SSIC continuously displays safety system status and enables operators to control safety systems. The proposed HMI has been evaluated using the checklists that are extracted from various human factors guidelines. From the evaluation results, it can be concluded that the HMI is so designed as to address the human factors issues reasonably. After sufficient validation, the concept and the design features of the proposed HMI will be reflected in the design of the main control room of the Korean Next Generation Reactor (KNGR).     

虚拟数控制造的建模与模拟研究

本文描述了虚拟数控零部件制造车间的建模与模拟结构,分析了设备模型和材料模型、虚拟车间模型、用户操作、数控零部件模型、虚拟车间模拟、模拟接口等模块的建立,讨论了虚拟数控制造的实时性和并行控制问题。     

基于单神经元的啤酒灌装液位自适应控制算法

目的为了提高啤酒灌装生产线的生产效率,提升制酒企业的自动化程度,降低工人的劳动强度。方法根据啤酒灌装流程以及自动灌装生产线结构,提出一种基于PLC和触摸屏的啤酒自动灌装生产线控制系统,控制系统以松下FP-XHC60R PLC为控制器核心,以威纶维纶MT6070I触摸屏为人机操作界面,通过PLC实现执行机构的自动控制和反馈控制,由HMI人机触摸屏实现生产线运行的参数设置,并监控生产线的运行状态。在此硬件结构基础上完成控制系统软件设计,并根据单神经元控制理论,提出一种啤酒灌装液位自适应控制算法,以提高灌装液位控制精度。结果该控制系统结构简单,便于操作人员对设备进行人性化管理。结论所设计的啤酒灌装生产线控制系统具有生产效率高、高度自动化、运行稳定等优点。     

全自动袋式包装生产线规格的柔性设计

目的以袋式包装生产线为对象,设计一条全自动袋式包装柔性生产线。方法将包装生产线划分为料仓、定量下料装置、包装材料放卷装置、真空热封合装置、切分装置、放袋装置、自动计数器、PLC程序控制及人机界面,并对各装置进行柔性化设计。结果形成了一条全自动袋式包装柔性生产线,并运用可靠性预计方法得出生产线的平均无故障工作时间为1164 h,满足实际生产需求。结论该生产线具有较强的灵活性和节约性,对缩短产品生产周期、降低生产成本、快速响应客户需求、实现敏捷生产具有重要的意义。     

Assessment of human–machine interface design for a Chinese nuclear power plant

A nuclear power plant (NPP) is a complex system but requires high reliability. The human–machine interface (HMI) design plays very important role in reactor safety. This paper describes an assessment on HMI design of a Chinese NPP, using a software system named Dynamic Interaction Analysis Support (DIAS). DIAS can give not only quantitative indices for dynamically assessing the HMI design, but also allow modify the values of these indices by taking into account human error probability during specified emergent operation procedures. The operation procedures dealing with postulated accidents and transients recorded from a full-scale plant simulator in the training center of a Chinese NPP were selected as references. According to the results of simulation and analysis, the potential problems in the HMI design and the operation procedures were detected. Suggestions to improve the HMI design and the operation procedures were addressed.     

Improving productivity of a multi-product machining line at a motorcycle manufacturing plant

This paper introduces a case study to improve productivity of a multi-product transmission case machining line at a motorcycle manufacturing plant. First, the manufacturing process is introduced to characterise the production flow. Through structural modelling, such a process is simplified through aggregations and transformed into a two-stage Bernoulli line model with split dedicated machines and finite buffers. Using Markov chain analysis, the system throughput can be estimated. The results are validated by plant data. To improve system productivity, through numerical experiments, we investigate the impacts of increasing machine efficiency, varying demands and implementing different loading policies. Such a study provides a quantitative tool for plant engineers and managers to improve production operations.     

工作研究在电器产品装配线平衡改善中的应用

针对粗放管理模式下温州企业普遍关注挖掘企业内部潜力,增强企业竞争力的问题,以温州某电器产品的装配生产线为研究对象,在运用程序分析方法规范产品生产工艺流程的基础上,采用秒表时间研究识别了生产线的瓶颈工位,通过工序重排、人员调整以及基于双手作业分析和动作分析的作业方法改进,使得生产线的平衡率提高了31％.     

基于五轴加工中心智能生产线的数字孪生应用研究

智能制造是我国近年来大力倡导的重点发展方向之一。随着智能制造试点的不断建立、发展和完善,数字孪生技术逐步得到应用。基于此,以五轴加工中心智能生产线为例,对数字孪生技术的应用情况进行总结。基于数字孪生技术,按1∶1的比例构建五轴加工中心智能生产线上实体设备的数字模型并配置对应的物理属性,使得数字模型具有与实体设备相同的动作状态。然后,对数字模型进行信号点设置并与外部控制信号进行映射与连接,实现对建成前五轴加工中心智能生产线的虚拟调试,并通过不断迭代获得最优的建设方案。实践结果表明,利用数字孪生可实现智能生产线组合、调试和生产的虚拟仿真;基于数字孪生的虚拟仿真功能,可实现产品物理属性参数和设计精准度的可视化展示,使得产品在设计阶段就能通过适应性验证,实现快速更新;在智能生产线建成后,利用数字孪生可实现对生产线上实体设备的管理及其工作状态的实时监控,以更好地了解各设备的运行状态。综上,数字孪生技术贯穿了智能生产线的全生命周期,可在智能制造领域推广应用。     

A robust optimisation model for production planning and pricing under demand uncertainty

The profitability of every manufacturing plant is dependent on its pricing strategy and a production plan to support the customers’ demand. In this paper, a new robust multi-product and multi-period model for planning and pricing is proposed. The demand is considered to be uncertain and price-dependent. Thus, for each price, a range of demands is possible. The unsatisfied demand is considered to be lost and hence, no backlogging is allowed. The objective is to maximise the profit over the planning horizon, which consists of a finite number of periods. To solve the proposed model, a modified unconscious search (US) algorithm is introduced. Several artificial test problems along with a real case implementation of the model in a textile manufacturing plant are used to show the applicability of the model and effectiveness of the US for tackling this problem. The results show that the proposed model can improve the profitability of the plant and the US is able to find high quality solutions in a very short time compared to exact methods.     

Virtual prototyping and manufacturing planning by using tri-dexel models and haptic force feedback

This paper presents a new method of using the tri-dexel volumetric models and a haptics force feedback for virtual prototyping and manufacturing planning. In the proposed method, the initial polyhedral surface model is converted to a tri-dexel volumetric model by using a depth-peeling dexelization algorithm. In the virtual prototyping process, the tri-dexel volumetric model is updated by the swept volume of a moving cutter via a haptic force feedback interface device. A collision detection algorithm is proposed for the virtual sculpting and the pencil-cut planning with real-time haptic force feedback to the users. Tool paths are generated for machining the virtual sculpted parts via the simulation and verification on a virtual CNC machine tool before they are actually machined. Computer implementation and practical examples are also presented in this paper. The proposed method enables the haptic-aided virtual prototyping and manufacturing planning of complex surface parts.     

Virtual prototyping and manufacturing planning by using tri-dexel models and haptic force feedback

This paper presents a new method of using the tri-dexel volumetric models and a haptics force feedback for virtual prototyping and manufacturing planning. In the proposed method, the initial polyhedral surface model is converted to a tri-dexel volumetric model by using a depth-peeling dexelization algorithm. In the virtual prototyping process, the tri-dexel volumetric model is updated by the swept volume of a moving cutter via a haptic force feedback interface device. A collision detection algorithm is proposed for the virtual sculpting and the pencil-cut planning with real-time haptic force feedback to the users. Tool paths are generated for machining the virtual sculpted parts via the simulation and verification on a virtual CNC machine tool before they are actually machined. Computer implementation and practical examples are also presented in this paper. The proposed method enables the haptic-aided virtual prototyping and manufacturing planning of complex surface parts.     

Reforming a conventional vehicle assembly plant for job enrichment

Although conventional conveyor-based vehicle assembly systems have proved to be very efficient in terms of plant productivity, it has also been recognized as a system which puts too much pressure on people. This paper introduces an alternative to conventional conveyor-based assembly lines, one that is designed to enrich the work environment of employees without sacrificing productivity. The reforming methodology suggested here applies the idea of cell manufacturing to the conventional conveyor-based assembly line system, but it does not require making any major changes to the existing hardware configurations of the plant. Benefits of the reformed line for workers include a longer cycle time, more balanced work loads, and greater protection against developing musculoskeletal disorders. To prove the effectiveness of the suggested methodology, we built a virtual factory model and performed simulations to assess the performance of the reformed line.