IC芯片粘片机并联焊头机构的静刚度分析

针对所设计的IC芯片粘片机的并联焊头机构,建立了机构的静刚度模型。使用M atlab软件绘出了机构在整个工作区间的静刚度特性曲线,并对左右驱动部分和连杆的刚度对其影响进行了分析。根据这些曲线,说明所设计的并联焊头机构能满足IC芯片粘片机的工作要求。     

重型数控立车工作台静压计算与优化

提出新的计算重型数控立车工作台刚性位移的方法和用于静压迭代求解的校正改进法。通过两个工况下的静压计算验证了新方法的有效性和稳定性。在此基础上,以工作台质量极小化为目标,建立包括结构和静压两个强耦合学科约束的优化模型,采用并行子空间设计方法进行优化。优化后工作台质量明显减小,表明了并行子空间设计方法的有效性。
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IC芯片粘片机并联焊头机构的弹性动力学分析

将IC芯片粘片机并联焊头机构的各高速运动杆件看作弹性杆件,用运动弹性动力分析的方法建立了机构的弹性动力学方程,并使用Newmark积分法求解出了方程在整个工作空间的弹性位移曲线。根据这些曲线,说明在计算焊头的运动精度和定位精度时,必须考虑焊头的弹性位移。     

并联运动机械结构综合及其优化设计研究的最新进展

综合评述了以德国为主的欧洲工业国在并联运动机械结构综合与设计方面的最新研究成果与进展,内容涉及：针对实际应用背景提出新机型并进行了设计;通过研制设计分析仿真软件,针对某种并联运动机械机型进行了结构综合改进与优化、尺度综合和优化以及性能评估与改善等工作;进一步地,在大量实践与理论探索的基础上,较系统地提出用于开发混合运动机械、冗余并联运动学以及可重构并联运动机械的设计方法学,这些内容都是并联运动机械设计研究领域内富有创造性的成果。

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IC芯片粘片机并联焊头机构的结构参数优化

分析了IC芯片粘片机并联焊头机构的工作空间,并以其全域操作性能为对象,在综合考虑机构全条件数的均值及其波动程度的条件下建立了机构的参数优化模型,最后利用Matlab软件对此模型进行了优化.     

基于功率键合图的IC芯片粘片机并联焊头机构的动力学分析

这里基于功率键合图的原理和特点,建立了IC芯片粘片机并联焊头机构的功率键合图模型和动力学方程,并用Matlab/Simulink进行了仿真。结果表明:使用该方法可以用简明的图形方式直观揭示出机构的动力学特征,动力学方程建立的规则化便于计算机自动生成。     

基于二元疲劳失效判据的非线性疲劳损伤累积模型及其强度退化研究

二元疲劳失效判据认为疲劳破坏是由损伤程度和当前作用应力这两个量共同决定的,由此观点出发定义了非线性损伤,并建立了与载荷状态有关的非线性损伤累积模型,推导了在多级加载下的递推公式。经两种金属材料的疲劳试验数据验证表明,用该模型预测疲劳寿命,其结果是令人满意的。从疲劳过程本质上是材料静强度不断退化的过程的观点出发,建立了基于二元疲劳失效判据的非线性强度退化模型,将模型应用于两级及多级载荷下的剩余寿命估算,结果表明,所提出的剩余强度退化模型是合理可行的。

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集装箱喷漆机器人逆运动学分析

集装箱喷漆机器人采用开式运动链,利用Denavit-Hartenberg方法建立五自由度串联型集装箱喷漆机器人的坐标系,采用解析法对机器人进行了逆运动学分析,然后在ADAMS下进行仿真,得到末端点的位移、速度和加速度曲线,验证了机器人机械结构的合理性,为集装箱喷漆机器人的快速设计与制造提供了理论依据。
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IC芯片粘片机的精度测量实验

设计制造出IC芯片粘片机焊头机构的实验平台．采用图像处理的方式来测量焊头的运动精度和定位精度等参数。实验结果表明：所设计的机构能满足IC芯片粘片机的工作要求，各项性能指标均达到了设计标准。     

基于PATRAN的机床结构快速动力学建模系统的开发

对机床固定结合面进行了研究,建立了机床固定结合部单元。在有限元软件PATRAN平台上,用PATRAN的二次开发工具PCL语言开发了机床结构快速动力学建模系统,利用DMIG数据卡片将实验数据输入到有限元软件PATRAN中,实现了有限元理论模型和实验模型的结合,提高了机床有限元建模的效率和精度。


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Design and control of a novel linear wire bonding head

Wire bonding has been one of the standard operations in plastic integrated circuit (IC) package assembly for a long time. With the development of IC assembly technology, the equipment of wire bonding should be improved for even higher performance. Thus, a novel linear wire bonding head driven by a permanent magnet linear motor (PMLM), instead of the rotary bonding structure, is designed to optimize the system structure and improve the performance of wire bonding. Based on two different wire bonding states, the switching control scheme corresponding to this linear structure is presented. In free motion, the position tracking control suppressing the vibration of flexible parts of the structure is performed at high speed and acceleration. In constrained motion, the active force control with direct contact force feedback is adopted for more precise bonding force compared with the indirect current feedback control in previous rotary structure. The experiment results show higher performance of wire bonding because of the combination of novel linear structure and control scheme.     

汽车电动助力转向系统电机匹配技术浅析

电机作为汽车电动助力转向系统中的动力元件,与整个系统进行有效的匹配显得十分重要。介绍汽车电动助力转向系统微特电机的种类和特点,提出电机与汽车电动助力转向系统之间的匹配方法,包括电压、转矩、转速、功率、电流脉宽调制、结构等的匹配。     

IC芯片粘片机并联焊头机构的运动学分析

针对所设计的IC芯片粘片机的并联焊头机构,建立了运动方程,给出了运动方程的正解,推导出速度、加速度的正、逆解。在已知左右驱动电机运动规律的情况下,使用Matlab软件得出了该机构X,y方向的速度、加速度曲线和位移曲线。研究结果表明,该机构运动平稳,位移曲线与预计的轨迹相符,能够满足工作要求。     

平面五连杆高速高精度机械手

针对微电子器件封装作业对高速高精度的自动设备的需求，提出了一种具有平面五连杆结构的机械手，机械手采用集成了高分辨率角位移反馈元件的旋转直接驱动电机作为驱动元件。并给出其运动学、动力学模型及雅克比矩阵。结合并联机构和直接驱动的优点，实现了高速高精度运动。     

Structural analysis of flagellar axonemes from inner arm dynein knockdown strains of Trypanosoma brucei

Trypanosoma brucei is a protozoan flagellate that causes African sleeping sickness. Flagellar function in this organism is critical for life cycle progression and pathogenesis, however the regulation of flagellar motility is not well understood. The flagellar axoneme produces a complex beat through the precisely coordinated firing of many proteins, including multiple dynein motors. These motors are found in the inner arm and outer arm complexes. We are studying one of the inner arm dynein motors in the T. brucei flagellum: dynein-f. RNAi knockdown of genes for two components of dynein-f: DNAH10, the α heavy chain, and IC138, an intermediate chain, cause severe motility defects including immotility. To determine if motility defects result from structural disruption of the axoneme, we used two different flagellar preparations to carefully examine axoneme structure in these strains using transmission electron microscopy (TEM). Our analysis showed that inner arm dynein size, axoneme structural integrity and fixed central pair orientation are not significantly different in either knockdown culture when compared to control cultures. These results support the idea that immotility in knockdowns affecting DNAH10 or IC138 results from loss of dynein-f function rather than from obvious structural defects in the axoneme.     

无轴承异步电机关键技术与发展趋势

无轴承异步电机集磁轴承和异步电机优点于一体,既能产生支承转子的径向悬浮力,又能产生驱动负载的电磁转矩,在高速机床电主轴、压缩机、涡流分子泵、计算机硬盘驱动等特殊场合具有广泛的应用前景。在介绍无轴承异步电机工作原理的基础上,对迄今为止出现的具有代表性的无轴承异步电机结构、数学模型以及控制技术进行了综述,针对目前无轴承异步电机的研究现状和不足之处,探讨了无轴承异步电机技术的研究方向和发展趋势,以期为进一步研究无轴承异步电机技术指明方向。     

贴片机系统中贴装头位置图像校准研究

贴装头位置校准是贴片机中元件贴装前关键的一步 ,目的是通过上照视觉系统检测贴装头中心以使其与之同心 ,从而保证元件贴装精度。研究出一种采用绕贴装头中心旋转、并等角度分布于圆周上的多幅图像信息 ,根据正多边形几心合一的特点 ,把贴装头中心定位到亚像素级精度 ,实现了高精度贴装头位置校准 ,同时分析了机械传动系统精度对校准过程的影响。     

JC120DB交流变频电机驱动单轴绞车设计

JC120DB交流变频驱动单轴绞车在主轴装置的两端分别有两台变频电机,电机通过联轴器与悬吊式一级半行星减速器的两个输入轴相连,经两级减速后通过齿轮离合器与主轴联接,在行星减速器与主轴之间有液压齿轮离合器.JC120DB绞车综合运用了行星减速技术、全数字交流变频控制技术、能耗制动与盘刹技术、自动送钻、智能软启动等新技术,整体技术性能先进,并具有体积小、质量轻、结构简单、效率高、使用维护简单、自动化程度高等特点.     

An integrated system for setting the optimal parameters in IC chip-package wire bonding processes

The wire bonding process is the key process in an IC chip-package. It is an urgent problem for IC chip-package industry to improve the wire bonding process capability. In this study, an integrated system is proposed to identify and control parameters in the wire bonding process in order to achieve high level performance and quality. First, an experimental design with Taguchi method is applied to identify the critical parameters in the wire bonding process. Then, an ANN is used to establish the nonlinear multivariate relationships between wire boning parameters and responses. Finally, a GA is adopted to find the most desired parameter settings by using the output of ANN as the fitness measure. Another popular method, response surface method, for parameter design problems is conducted for comparison purpose. Results of this comparison demonstrate the effectiveness of the proposed approach.     

Diagnostics of stator faults of the single-phase induction motor using thermal images,MoASoS and selected classifiers

Single-phase induction motors are used in the industry commonly. Induction motors are not expensive, so it is a reason to use them. Diagnostics of faults is very important. It prevents financial loss and unplanned downtimes causes by faults. In this paper the authors described fault diagnostic techniques of the single-phase induction motor. Presented techniques were based on the analysis of thermal images of electric motor. The authors measured and analysed 3 states of the single-phase induction motor. In this paper an original method of the feature extraction of thermal images called MoASoS (Method of Area Selection of States) was presented. The proposed method - MoASoS and an image histogram were used to form feature vectors. Classification of the obtained vectors was performed by NN (Nearest Neighbour classifier) and Gaussian Mixture Models (GMM). The described fault diagnostic techniques are useful for reliability of the single-phase induction motors and other rotating electrical machines such as: three-phase induction motors, synchronous motors, DC motors.