电火花雕刻加工自动编程

介绍了电火花雕刻加工的图形自动编程系统。该系统以工件图的DXF图形交换文件为输入，采用分层去除策略生成实体的截面轮廓线并对截面轮廓线进行插补以达到工件的加工精度要求，经过工艺分析和处理，自动生成NC代码，并进行加工仿真。     

卧式加工中心MDH80的刀具破损自动重起功能

通过对刀仪对刀具的测量数据和刀补值的比较,判断刀具破损.破损后,跳过当前刀具,自动调用备用刀具,重新加工新工件.     

形体探测技术应用于激光加工

将形体探测技术用于激光加工,收效显著。此系统具有3～8轴加工能力,可加工如医疗机械等非常小的薄壁件和卡车以及喷气飞机等非常大的金属薄板工件。形体探测装置与激光切削加工系统的自控调焦部分匹配工作的过程是:自动地交叉扫描工件或工件夹具的形体并确定射束释放头与工件或工件夹具之间的距离,迅速分析这些数据以确定距离最小的位置,并自动发出一个信号给激光加工系统以指导切削射束的加     

基于机器视觉的数控自动编程系统开发

基于机器视觉的数控加工技术综合运用机器视觉技术和数控加工技术,直接利用视觉图像数据实现数控加工编程。将机器视觉技术应用于数控加工编程技术中,构造出基于机器视觉的数控自动编程系统。通过机器视觉采集系统来获取工件图像,并对图像进行处理得到工件图元的边缘轮廓。进而将加工的边缘轮廓进行矢量化处理得到数控加工轨迹,并最终根据加工工艺参数的设定转化成数控加工程序,实现了工件的自动编程。     

数控机床在线测量系统的分析

对使用在线工件测量系统的数控加工机床进行了介绍,从工件定位、加工余量自动分配、加工过程监控和加工结果检测等方面对在线测量系统的应用进行了论述,并对数控机床在线测量系统的前景进行了展望。     

五面体加工中心零点计算公式的使用

针对实际工作中工件进行多面加工时零点计算的繁琐性和多次找零点的不准确问题,阐述了五面体加工中心加工时零点的简便计算过程,总结出各个加工面之间变换时零点的计算公式,并将其编成子程序.使用时只需调用子程序就能自动完成零点的计算,省去了大量的繁琐工作,减轻了工人的劳动强度,提高了工作效率和加工精度.     

改善接刀痕迹的编程技巧

在对由直线和圆弧组成的工件轮廓形状进行数控车削加工时,经常遇到产生接刀痕迹的问题.以数控车削加工图1所示工件为例:加工机床为广州数控设备厂生产的GSK980T数控车床,粗车加工采用55°右偏车刀,精车加工采用35°外圆车刀.加工工件右端外圆、外锥时调用G71指令,加工φ28mm外圆弧槽时调用G73指令,精车加工时调用G70指令.工件原点设在工件右端面,加工φ28mm外圆弧槽的程序如下:     

HNC-21TF数控车床自动刀架电气控制系统设计

数控车床的自动回转刀架可以在工件一次装夹中调用多把刀具进行多工序加工。通过对华中世纪星HNC-21TF车床数控系统的自动刀架进行研究,分析了刀架的电气控制过程,给出了刀架控制的电气原理图和PLC程序。最后对刀架可能出现的故障现象进行了分析,并给出了故障排除方法。     

用于加工中心的在线工件自动测量系统

介绍一种可用于加工中心的在线工件自动测量系统的构成及功能。该系统采用新型触发式传感器 ,可使刀具刀尖自身作为测头测试工件加工尺寸。该系统可用于工件的装夹找正 ,也可对工件进行自动在线测量 ,并能根据测量结果对加工误差进行补偿以提高加工精度     

在线测量技术在前端盖加工中的应用

在数控机床上对被加工工件进行在线自动测量是提高数控机床自动化加工水平和保证工件加工精度的有效方法,因此,数控机床工件在线自动测量系统是衡量数控机床技术水平的     

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.     

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....     

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。     

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.