RFID技术在离散制造业物料配送中的应用研究

针对离散制造业中物料配送不及时、准确性差的问题,在分析离散制造业物料配送业务流程的基础上,运用RFID技术对离散制造业内物流配送过程中的物料信息进行实时采集和处理,通过平板电脑进行电子签收。设计了企业内物料配送系统的功能结构,并进行试点应用,物料配送过程实现了可视化,提高了物料配送的准确率。     

电视制造业元器件自动配送开发设计

通过对电视机制造企业生产装配过程中零部件成套性与产品BOM的分析研究,结合产品的工艺流程,提出了包括传送锟道,分拣平台、条码信息软件系统在内的电子元器件配送模型,描述了物料配送系统的结构、分拣原理、特点和应用,实现了车间零部件成套配送和控制,把物料运送到工位.运行结果显示此系统提高了仓储物料分拣效率.     

基于MES的焊装车间物料管理系统设计

针对焊装生产线的物料管理系统数据管理分散、缺乏物料跟踪以及信息反馈慢的缺点,应用面向MES的物料配送模型,设计了一种基于SIAMTIC IT的焊装生产线物料管理MES系统,着重分析了物料跟踪与配送开发过程、实现方法和运行结果,实现了实时记录焊装过程的零部件和产品属性信息。     

基于无线网络的制造业物料配送系统的设计*

针对制造业传统物料配送系统存在的缺点,基于业务流程再造的理念,运用无线局域网技术设计了全新的物料配送系统。该系统能够对配送流程进行优化,提高了配送效率,有效地解决了配送不及时所造成的生产速度瓶颈问题。     

一种拖车式医用配送机器人的设计与实现

应急防控智能机器人在疾病防控中扮演着重要的角色.针对疫情防控过程中出现的物料配送不足问题,设计了一种医用配送机器人,采用拖车式结构,将立体循环车厢与机械手结合实现递送服务.系统采用了装有ROS系统的MiniPC和STM32单片机,实现了机器人自主定位导航和机械手通过视觉识别完成抓取动作等功能.样机的实验结果显示,系统实现了设计功能,实现了配送过程的全程自动化.     

无线局域网在制造业物料配送中的应用研究

从物流管理和流程再造的角度对具有前沿代表性的某大型汽车制造企业的物料配送的管理工作进行了研究,找出了其物料配送信息化中的物料配送流程及库存盘点存在的问题。用新兴的无线局域网信息技术,把无线管理理念和原有的业务流程进行了有机的整合,再造业务流程。按照新的物料配送流程并结合企业的自身特点,分别从结构、功能角度设计新系统,解决了原有系统中存在的问题。     

航空发动机加工现场生产制造网络化协同系统

为解决航空发动机加工现场存在的物料管理手段缺乏、物料无法拉动、生产要素采集少、可视化手段少等问题,本文实现了一套面向航空发动机生产制造过程的网络化协同环境,对生产过程关键要素数据的采集、追踪、分析和处理,通过物料拉动配送系统、生产要素采集系统、可视化看板系统,实现物料线边拉动优化、数据展示端业务报表优化、生产关键要素信息采集、制造端数据集成等内容。     

汽车零件制造企业物料配送模式优化

传统的汽车零件制造企业的物料配送模式一般都比较落后,需要比较冗余的物料拉动机制,物料配送数量的确定更是依赖于工人的经验。为了实现精确高效的物料配送,设计了一套优化的物料配送模式,并针对优化过程中的需要解决的信息共享问题提出了一套解决方案。     

混流生产线物料索取系统的设计及实现

为完善和优化制造企业生产物流配送管理模式,结合JIT精益物流管理思想,提出了一种通过对混流生产线上短缺物料发送需求指令驱动物料配送的配料模式.设计并实现了一种基于B/S和C/S混合模式的物料索取系统,该文对系统的模型建立、功能实现以及关键技术进行了详细的阐述.该物料索取系统已应用于某企业装配生产线,试运行结果表明物料配送效率得到显著提高.     

混流制造车间物料配送路径优化

物料及时、准确送到混流制造系统的各工位节点不仅是系统正常运行的保证,也是混流系统高效运转的根本。针对混流制造系统物料配送车辆路径优化问题,从优化目标、约束条件和影响因素等方面考虑,建立了以车辆行驶距离最短、车辆利用率最大和配送次数最少为优化目标的多目标配送车辆路径优化模型。根据问题的具体情况,设计了解决该多目标优化问题的双层递进进化多目标优化算法,给出了算法的进化过程和交叉、变异模式及其实现过程。通过一个混流装配系统的实例证明了所建立的模型和设计算法的有效性。     

固化冷却过程中复合材料参数对其应变的影响

为有效降低某复合材料固化冷却过程中的应变水平,以某圆柱形复合材料为例,利用有限元分析软件MSC Nastran,研究固化冷却过程中复合材料参数对其应变的影响.计算得到复合材料最大von Mises应变值和分布位置,分析弹性模量、泊松比、线膨胀系数、密度等参数对其应变的影响.     

Multidisciplinary shape optimization of ductile iron castings by considering local microstructure and material behaviour

During the casting process and solidification of ductile iron castings, a heterogeneous microstructure is formed throughout the casting. This distribution is strongly influenced by the item geometry and the process related factors, as chemical composition and local solidification conditions. Geometrical changes to the geometry of the casting thus alters the local mechanical behavior and properties, as well as the distribution of stresses and strains when the casting is subjected to load. In order to find an optimal geometry, e.g. with reduced weight and increased load-bearing capacity, this interdependency between geometry and local material behavior needs to be considered and integrated into the optimization method. In this contribution, recent developments in the multidisciplinary integration of casting process simulation, solidification and microstructure modelling, microstructure-based material characterization, finite element structural analyses with local material behavior and structural optimization techniques are presented and discussed. The effect and relevance of considering the local material behavior in shape optimization of ductile iron castings is discussed and evidenced by an industrial application. It is shown that by adopting a multidisciplinary optimization approach by integration of casting simulation and local material behavior into shape optimization, the potential of the casting process to obtain components with high performance and reliability can be enabled and utilized.     

Temperature distribution in a moving material subjected to surface energy transfer

A numerical study of the thermal characteristics in a continuously moving system, such as the crystal growing process, has been carried out. In several manufacturing processes, the material is continuously fed and the temperature distribution in the material is to be determined as a function of the physical variables in the problem. The study considers the one-dimensional, two-dimensional and axisymmetric cases of a heated material which moves at a given velocity. The transient as well as the steady-state problems are considered and the temperature distribution is obtained as a function of the Peclet number, which determines the relative importance of the motion, of the Biot number and of various other governing parameters in the problem. The transient problem is a moving boundary circumstance and a numerical scheme is developed to study the time-dependent length of the material and the temperature distribution. The steady-state temperature distribution is also obtained. Results are obtained over a wide range of governing parameters and are discussed in terms of the basic mechanisms. Several very interesting features are observed and the importance of the work in practical systems is outlined.     

A hierarchical genetic algorithm with age structure for multimodal optimal design of hybrid composites

A genetic algorithm aiming the optimal design of composite structures under non-linear behaviour is presented. The approach addresses the optimal material/stacking sequence in laminate construction and material distribution topology in composite structures as a multimodal optimization problem. The proposed evolutionary process is based on a sequential hierarchical relation between subpopulations evolving in separated isolation stages followed by migration. Improvements based on the species conservation paradigm are performed to avoid genetic tendencies due to elitist strategies used in the hierarchical subpopulations. The concept of species is associated with material distribution topology in composite structures, and an enlarged master population with age structure is considered concurrently with the hierarchical topology. Rules based on species concept are imposed on either isolation or migration stages to overcome the predominance of a species and to guarantee the diversity. A mutation process controlled by the stress field is implemented, improving the local genetic search. The proposed model allows multiple solutions for the optimal design problem.     

Determining the production lot size with a heuristic inspection policy for controlling the quality of input materials and products

This study simultaneously determines the optimal production lot size and an inspection policy for input materials and products, where an unreliable process produces products with a discrete general shift distribution. This work proposes a heuristic inspection policy for materials and products, by first obtaining the inspection range for the input material without considering product inspection, and by further determining the product inspection range based on the obtained range of the input material inspection. The optimal inspection policy shows that common policies of no or full inspection are never optimal. This study includes the optimal production lot size based on the obtained inspection policy. Numerical examples demonstrate the impacts of input quality level, process reliability and unit nonconforming cost on the optimal solution, which adopts a discrete Weibull shift distribution to model the process failure time. Finally, this study addresses the conclusions.     

基于本体的仿真系统元概念模型研究*

在仿真系统的概念模型开发过程中存在着模型重用性不高和缺乏管理等问题,这些问题将影响模型开发效率和仿真系统的可靠性.为解决以上问题,提出了元概念模型(MCM)的概念,以实现在更高层次对概念模型进行抽象.将本体思想引入MCM的设计中,提出了基于本体的元概念模型(OMCM)建模方法,并给出了OMCM的层次结构和建模方法.最后,将该方法应用于装备保障仿真系统元概念模型的建模中,得到了较好的验证.     

控制超塑性充模胀形过程的计算机仿真技术

运用刚粘塑性有限元法，对控制超塑性充模胀形过程的计算机仿真技术研究包括：本构关系确定，接触摩擦约束处理，载荷控制算法及其优化，数据采集实时处理，计算机自动控制系统研制。基于刚粘塑性有限元法的最大应变速率恒定法可将压力加载过程控制在最佳状态（优化的Ｐ－Ｔ曲线）；改善了钣料胀形轮廓的厚度分布状况。本文的研究解决了控制超塑性充模胀形过程中的主要问题：数据形成、采集、处理、传输、控制；对变化的压力加载曲线能实现计算机可视化实时控制；所预示的胀形件壁厚变薄趋势与实验结果吻合；缩短胀形时间；实现了一次胀形成功的目的。     

Multi-physics interpolation for the topology optimization of piezoelectric systems

Unlike single-physics static structural problems, the topology optimization of piezoelectric systems involves three different material coefficient groups, such as the mechanical, electrical, and electromechanical coefficient groups, which correspondingly necessitate three values of penalty exponents. Earlier investigations have shown that stable convergence cannot be ensured if the exponents are selected arbitrarily or based simply on typical rules used for static structural problems. Here, stable convergence implies that the use of more materials can yield better system performance and a distinct void–solid distribution is favored over an intermediate material distribution during the optimization process. However, no rule for choosing the values of penalty exponents has yet been studied for piezoelectric systems and in fact, they have been chosen mainly by trial and error. In this work, two conditions that the three penalty exponents must satisfy for stable convergence are derived for one-dimensional problems and their effectiveness for two-dimensional problems is investigated. The first condition is an intrinsic condition ensuring better energy conversion efficiency between mechanical and electric energy for more piezoelectric material usage and the second one is an objective-dependent condition favoring a distinct void–solid distribution over an intermediate material distribution for the same amount of piezoelectric material used. In this study, we consider the design of piezoelectric actuators, sensors and energy harvesters that can be analyzed by static analysis. Several numerical examples are solved to check the validity of the proposed conditions.