基于DSP的SMT贴片机运动控制卡设计

一 序言 SMT贴片机是一个视觉机器人系统．由X-Y-Z-θ4个自由度机械手，PCB板传输定位系统．元器件上料系统和视觉系统构成。决定贴片速度和精度是机械手的运动控制。开放式的运动控制技术利用了近年来电子、网络通信、计算机和控制理论等领域的新成果．通过对以电机驱动的执行机构等设备进行运动控制，以实现预定运动轨迹目标的装置．用于完成多个运动轴（2～32轴）位置、速度和同步的控制。本运动控制系统的任务是研制高速高精度视觉贴片机DSP多轴运动控制卡．同时实现4个轴（如图1）的位置控制，研究高速度、高加速度运动与贴片精度的难题。     

多功能贴片机系统管理软件设计及实现

针对多功能贴片机的高速、高精度和控制需求,本文分析了贴片机系统管理软件的整体架构和三个最重要的核心模块:PCB数据管理、视觉检测及定位、运动控制;本文重点介绍了三个核心模块的有关程序实现技术及主要视觉算法实现。该系统管理软件在研制的多功能贴片机样机上得以初步应用。     

高精度贴片机视觉定位系统的研究与设计

针对高精度贴片机视觉系统的功能要求，对单臂式贴片机视觉系统的工作流程进行了研究，并据此设计其功能结构和硬件排布，提出了一种适用于单臂式贴片机的光路成像系统。最后，搭建了贴片机视觉系统实验平台并对本文设计的光路成像系统进行的实验验证，结果证明此新型视觉成像系统可以满足高精度贴片机的对成像系统可控性及成像精度的要求。     

高精度全视觉贴片机的系统软件设计与实现

高精度全视觉过顶拱架型贴片机的系统软件设计是一项复杂的软件工程项目.在分析贴片机基本工作过程的基础上,构造了系统软件的总体结构和功能模块,详细分析了系统软件的三个最重要的核心模块:数据管理模块、控制模块、视觉模块.综合应用这三个核心模块,设计了贴片机的自动贴装程序流程.软件设计方法和步骤在所研制的全视觉贴片机祥机上获得成功应用.     

贴片机的虚拟样机研究

以贴片机为对象，研究虚拟样机技术在贴片机开发中的实际应用。首先使用UG软件对三种贴片机进行了三维实体建模，然后导入动力学仿真软件ADAMS，产生贴片机的“虚拟样机”，再对贴片机进行运动仿真分析，得出了运动学和动力学参数，为今后物理样机的设计和制作提供依据。     

FCS系统在贴片机的位置偏差校正中的应用

准确的定位技术是SMT表面组装生产线上主流设备贴片机的主要性能指标,贴片机的定位系统成为高性能贴片机最为关键的系统之一。以激光校准传感器作为贴片机的视觉定位检测系统,使贴片机自身具有识别贴片位置偏移的自动校正功能,满足小型元件的贴片精度要求,且提高对θ轴马达的强化,实现了面向大型元件的对应能力。结果表明:激光识别自动校正系统FCS在贴片头中的应用,通过非接触定心方式,LED激光多角度照射,光影宽度与切线数据的获取,使用最小二乘法准则完成元件形状分析,位置偏差校正,实现贴片元件精准定位的工艺要求。     

运用区域生长法的贴片元件定位识别算法研究

讨论了贴片机机器视觉系统中元件识别的机器图像处理的实现方法,针对贴片机中贴片元件(IC)高精度定位的要求,采用了以区域生长法为基础的元件中心和角度的计算方法,通过算法的耗时实验以及重复精度测试实验,验证了算法的可行性,得出了基于区域生长法的贴片元件定位识别算法,可满足高精度贴片的要求.     

高速高效贴片机控制系统设计与实现

介绍了高速高效贴片机的结构和功能划分,结合开发的高速高精度双臂多头贴片机样机,分析了其控制系统的要求。详细阐述了高速高效贴片机基于工控机+GT系列控制卡模式控制系统的软、硬件设计方法。针对贴片头多吸嘴同时吸贴的特殊结构的使用要求,在图像处理环节采用像素标记法对多元件目标进行图像分割处理,给出具体算法流程,并通过仿真说明了该方法具有较好的识别效果。样机的实际应用证明,控制系统及视觉处理满足了高速高效贴片机的使用要求。     

基于加减速控制和刚柔耦合的贴片机位置精度分析

针对贴片机高速高精度的控制要求,采用梯形曲线加减速控制和S曲线加减速控制两种控制方式。通过对贴片机刚性体模型和刚柔耦合模型的运动仿真,证明S曲线加减速控制能够克服梯形曲线加减速控制的缺点,具有平稳性好、冲击力小和位置精度高的优点。     

桌式贴片机横梁的模态分析及拓扑优化设计

贴片机是一种通过视觉定位、智能控制,快速移动贴片头,将元器件精准、快速地贴装在PCB板上的高精度机械电子设备。桌式贴片机一般用于实验室或者小型电子公司,属于贴装量相对较少的中小型贴片机。横梁是贴片机最重要部件之一,承载着贴片机的运动系统,其动态性能将直接影响贴片质量。首先建立横梁的有限元模型,并对其进行模态分析,然后在此基础上对横梁拓扑优化,将优化结果与最初模态分析结果对比,最终在保证动态性能的基础上,得到一种更为可靠的横梁结构。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.