矿用设备开停传感器试验工装的设计

针对传统的采用交流三相电源加上大功率电热炉或灯泡来获得矿用设备开停传感器动作所需电流的测试方式存在的接线复杂、难以实现电流的连续控制、测试效率低等问题,提出了一种矿用设备开停传感器试验工装的设计方案,给出了相关设计要求,详细介绍了试验工装的组成及主要电路设计。对某矿用设备开停传感器的实际检测检验结果表明,该试验工装能够产生连续可调的电流,检验过程简单,效率较高,并可通过使用计量合格的钳形表进行校准,实现了数据准确性和可溯源性的目标。     

Analyzing engineering change of aircraft assembly tooling considering both duration and resource consumption

Aircraft assembly tooling is developed according to the constraints of geometric information and technical requirements of aircraft, and frequent aircraft changes can cause assembly tooling tasks to change frequently. Assembly tooling parts are large in amount and complex in structure. Due to the complex dependencies among the tasks of assembly tooling, change in one task can cause changes to many other tasks, which may require much time and resources to completely resolve them. However, long cycle and mass resource consumption for the engineering change would normally lead to high risk, high cost, high rework, and so on. The primary result of this work is the provision of a development support to find the optimal solution of assembly tooling change by examining the combined effects of duration and resource consumption. In this paper, engineering change progression of assembly tooling is modeled as a decrease of impact on affected tasks, which implies that the duration of certain changed task reduces gradually. Besides, a deterministic simulation model is developed to analyze the change propagation schemes. The model explores the combined effects of task parallelism, resource constraints and change propagation during the engineering change process of assembly tooling. Finally, a case study of an assembly tooling for the reinforced frame module is implemented and the analysis results suggest that the proposed method offers a valuable basis for providing targeted guidance on how to obtain the optimal engineering change scheme of assembly tooling.     

Automated tool management in flexible manufacturing

The need for automated tooling in flexible machining, assembly, and sheet fabrication systems is reviewed. The various methods of implementing these systems, their benefits and drawbacks are discussed. The basic modules of automated tool transfer, storage, loading/unloading, and management are described together with the appropriate level of automation for each module. The advantages and prerequisites for unmanned machining systems, the current sensing methods and the tool replacement strategies are also reviewed. The importance of a tool database, its uses and structure are highlighted. Finally, the design and evaluation of automated tooling systems and operating strategies, with the aid of discrete events computer simulation are discussed. An existing computer package which is capable of simulating automated tooling systems for flexible manufacturing systems is presented.     

Computer-aided tool selection for turning and boring

This paper presents an approach for automated selection of tools for turning and boring operations. A prototype is presented that considers all toolholder and insert parameters in the selection process. The design offers flexibility, expandability, and the capability of selecting tools from any tool manufacturer. The resulting software system could be used by a machine manufacturer, a tool consultant, or a shop-floor engineer to modify existing tooling on the machine, recommend new tooling for a product, and solve tool-related problems.     

Kinematic calibration of a five-bar planar parallel robot using all working modes

We present a simple low-cost calibration procedure that improves the planar positioning accuracy of a double-arm SCARA robot to levels difficult or impossible to achieve using an equivalent serial robot. Measurements are based on the use of five custom designed magnetic tooling balls fixed to the periphery of a detachable working plate. Three of these tooling balls define the world reference frame of the robot, and the positions of the centers of all balls are measured on a CMM. A special magnetic cup end-effector is used. Measurements are taken by manually positioning the end-effector over each of the tooling balls, with each of the maximum of four possible robot configurations. Each of these measurements is repeatable to within±0.015 mm. The robot calibration model includes all 12 kinematic parameters, and the calibration method used is based on the linearization of the direct kinematics model in each calibration configuration. The optimal number and location of the tooling balls is obtained by studying the observability index. Finally, an experimental validation at 14 additional tooling balls shows that the maximum position error with respect to the world frame is reduced to 0.080 mm within the entire robot's workspace of 600 mm×600 mm.     

基于MBD的飞机工装数字化定义与管理技术研究

为在飞机工艺装备上应用基于模型定义（MBD）技术,结合飞机工装特点,对工装MBD模型的定义与管理技术进行了研究。首先,构建了工装MBD的数学模型,阐述了通过几何元素、特性和标注的方式完整描述模型的方法,并对工装需求信息进行了具体定义和分类说明。然后,详细探讨了工装模型非几何信息的管理方法,介绍了基于集成界面分类显示的特性管理模式和基于三视图的标注管理模式,并研究了标注信息分类显示的方案。最后,在CATIA V5R18平台上利用组件应用架构（CAA）技术开发了工装MBD定义与管理系统。该系统已在某大型航空企业工艺装备部门得到了应用。     

基于PMAC的航空结构件柔性工装分布式控制系统设计

航空结构件是航空飞行器中的重要组成部分，航空结构件的自动化柔性工装质量直接影响航空飞行器的飞行安全水平。为降低系统位置和姿态控制误差，减小航空结构件的磨损面积，设计了基于PMAC的航空结构件柔性工装分布式控制系统。采用PMAC运动控制器，接收电子部件的反馈信号，控制步进电机、直流电机和交流电机。结合工控机、定位器、伺服电机和分布式通信网络，完成硬件系统的设计。根据航空结构件柔性工装操作设备的组成结构和工作原理，构建相应模型。确定航空结构件在目标曲面上的柔性工装位置，从移动位置和装配力两个方面，计算柔性工装控制量。在PMAC控制器的作用下，通过位姿的调整实现系统的航空结构件柔性工装分布式控制功能。系统测试结果表明，设计分布式控制系统的位置和姿态控制误差分别降低了13cm和0.32°，且设计系统控制下航空结构件的磨损面积较小。     

基于机器人弧焊的快速金属模型模具制造

基于分层制造概念的纯金属模型的制造是当今快速成型领域的热门研究课题 .机器人焊接是一种可以实现精密焊接的焊接方法 ,将机器人弧焊与分层制造结合即实现了金属模型甚至模具的快速制造 .本文论述了工作过程的基本概念和主要工作难点 ,指明了研究过程中的努力方向     

Tool-provisioning strategies for flexible manufacturing systems

The difficulties encountered in managing the tool flow in flexible manufacturing systems for the manufacture of prismatic parts indicate the requirement to handle operational issues such as tool assignment. The choice of operational strategy and its relationship to machine specification, work and tool loading, scheduling and specific mode of tool management may significantly enhance machine utilization and work throughput. In this paper, strategies are presented aimed at improving system efficiency and minimizing tooling costs by considering tool provision as work-orientated, where the tooling is changed to suit the production task, or tool-orientated, where resident tools dictate the work flow, or a combination of the two. This paper draws on evidence from current industrial practice and recent developments.     

铜材连续挤压的腔体温度控制方法

在铜材连续挤压生产中,腔体温度的高低对产品的质量、挤压轮和模具的使用寿命有很大的影响,而腔体温度又受到许多因素的影响。为解决生产过程中依靠人工调节腔体温度难的问题,通过实验测定的方法建立了被控对象数学模型,比较PID控制器和模糊控制器的性能,提出一种腔体温度自动控制方法。该方法应用在TLJ300铜扁线连续挤压生产线上,解决了腔体温度靠人工控制难的问题,很大地提高了劳动生产率和产品质量,延长了挤压轮和模具的使用寿命。     

应用数字化技术提升工装设计水平

本文通过对数字化技术在工装设计中的应用现状和今后发展方向进行阐述,介绍CAD、UG、PDM系统在工装设计中的重要地位。     

数控加工工装物流自动控制系统的设计

数控加工技术以其加工过程人工干预少、加工效率高、产品质量稳定等优点在现代航空制造领域得到了广泛的应用。然而,因航空产品更新换代快、新研项目多,零件加工过程中对工装使用极为频繁,所以传统纯人工物流方式耗时多、速度慢、占居空间大等缺点尤为凸显。本自动控制系统通过对数控加工过程中的工装物流环节进行科学管理,实现工装自动存取、调配,减少数控加工的辅助时间,进一步提高数控加工的生产效率。     

Design and analysis of a reconfigurable discrete pin tooling system for molding of three-dimensional free-form objects

This paper presents the design and analysis of a new reconfigurable tooling for the fabrication of three-dimensional (3D) free-form objects. The proposed reconfigurable tooling system comprises a set of matrices of a closely stacked discrete elements (i.e., pins) arranged to form a cavity in which a free-form object can be molded. By reconfiguring the pins, a single tool can be used in the place of multiple tools to produce different parts with the involvement of much lesser time and cost. The structural behavior of a reconfigurable mold tool under process conditions of thermoplastic molding is studied using a finite element method (FEM) based methodology. Various factors that would affect the tool behavior are identified and their effects are analyzed to optimally design a reconfigurable mold tool for a given set of process conditions. A prototype, open reconfigurable mold tool is developed to present the feasibility of the proposed tooling system. Several case studies and sample parts are also presented in this paper.     

Optimization of machine setup and tooling using the principles of group technology

A number of the problems which arise in batch manufacturer are a result of the high variety of components produced. One of the basic features of group technology is to reduce this variety by effectively sorting components requiring similar processes into families to increase efficiency and productivity.This paper presents a research project to study and optimize the choice of toolings, tooling setups and scheduling of component parts to be machined on different kinds of turning machines. A computer program called OPSSP (OPtimization of Setup and Scheduling of Parts) was developed to achieve this goal. Furthermore, as a step toward the completion of automated process planning of parts, the system is designed to select appropriate holders for cutting tools and prepare detailed work instructions containing the clamping device and a list of required tooling for parts.The verification studies indicated that the system is capable of producing realistic practical results and can be effectively be used to achieve effective tooling, setup, and processing of parts.     

An architecture for the vertical integration of tooling considerations from design to process planning

To meet the competitive demands of modern manufacturing, it is necessary to reduce design times and enrich decision making by integrating process planning into the design activity using Concurrent Engineering principles. Although this is traditionally done through the interaction between designers and process planners, it is perhaps more desirable for a CAD system to have the functionality necessary to automatically advise the designer of the shop floor implications of design decisions. Cutting tool selection is an essential thread linking feature-based design of machined parts to process planning. Thus, the implementation of tooling considerations into design is an important requirement for an integrated CAD/CAPP system. This paper defines an architecture to enable the vertical integration of tooling considerations from early design to process planning and scheduling. The architecture is based on a five-level tool selection procedure which is mapped to a time-phased aggregate, management and detailed process planning framework. This paper draws on literature and the results of an industrial survey to identify the tooling methods suitable for integration within a CAD system and categorises them into the five levels of tool selection. The functions are then placed on a time-dependent framework that covers the progression of a product from design to process planning. The new functionality is being implemented as an object-oriented application called VITool, which is being developed so that it can be fully integrated within an existing CAD system.     

Classification knowledge discovery in mold tooling test using decision tree algorithm

The scale of Taiwan’s mold industry was ranked the sixth in the world. But, under the global competitive pressure, Taiwan has lost its competitive advantage gradually. The only chance of Taiwan’s mold industry lies in improving the competitive abilities in product research, development and design. In mold manufacturing cycle, mold tooling test plays a very important role at accelerating the speed of production. An experienced engineer can minimize the error rate of mold tooling test according to his rich experiences in parameter adjustment. However, this experience is mostly implicit without theoretical basis and its knowledge is difficult to be transmitted. Benefiting from the well development of data mining technologies, this study aimed at constructing an intelligent classification knowledge discovery system for mold tooling test based on decision tree algorithm, so as to explore and accumulate the experimental knowledge for the use of Taiwan’s mold industry. This study took the only high-alloy steel manufacturer in Taiwan for case study, and performed system validation with 66 record data. The results showed the accuracy rates of prediction of training data and testing data are 97.6 and 86.9%, respectively. In addition, this study explored two classification knowledge rules and proposed concrete proposals for tooling test parameter adjustment. Moreover, this study provided two ways, rule verification and effectiveness comparison of four mining algorithms, to conduct model verification. The experimental results showed the decision tree algorithm has an excellent discriminatory power of classification and is able to provide clear and simple reference rules for decisions.     

Machining times and costs analyzed on a programmable calculator

Two sets of programs for analyzing machine shop operations have been developed for application by a programmable calculator. The first set generates time standards for a wide variety of metal cutting and grinding operations: the second per performs an analysis of the costs of labor, machinery, and tooling.Thiis latter analysis also produces the optimum machine speed to employ to minimize production time or cost, or to maximize profit.     

A taxonomy of tool-related issues affecting the adoption of model-driven engineering

Although poor tool support is often blamed for the low uptake of model-driven engineering (MDE), recent studies have shown that adoption problems are as likely to be down to social and organizational factors as with tooling issues. This article discusses the impact of tools on MDE adoption and practice and does so while placing tooling within a broader organizational context. The article revisits previous data on MDE use in industry (19 in-depth interviews with MDE practitioners) and reanalyzes that data through the specific lens of MDE tools in an attempt to identify and categorize the issues that users had with the tools they adopted. In addition, the article presents new data: 20 new interviews in two specific companies—and analyzes it through the same lens. A key contribution of the paper is a loose taxonomy of tool-related considerations, based on empirical industry data, which can be used to reflect on the tooling landscape as well as inform future research on MDE tools.     

Discussion of tooling solutions for the direct bonding of silicon wafers

Silicon-to-silicon fusion (or direct) pre-bonding is an important enabling technology for many emerging microelectronics and MEMS technologies. A silicon–silicon direct bond can be easily formed, where the wafer surfaces are highly flat and very clean (Tong and Gosele), however for practical structured MEMS devices, wafer bow and local roughness may be compromised such that it is no longer a trivial task to achieve a direct bond. Tooling has been developed to facilitate the in situ alignment and bonding of silicon-to-silicon wafers in a vacuum chamber. The rate and direction of the bond propagation are controlled, thus minimising the occurrence of non-particle related voids. The tooling system also allows wafers with “non-ideal” surfaces or warped profiles to be bonded, by maximising the area across which bonding occurs and providing in situ annealing. The ability to anneal the wafers while maintaining clamping force creates attractive forces high enough to overcome the mechanical repulsive forces between the wafers and maintain a permanent bond. The tooling system can also be configured to give control over the bow or residual stress in the bonded pair, a factor that is critical in multi-stack direct wafer bonding.