圆度误差测量数据采集系统设计

介绍了自制圆度测量装置的测量原理和自动测量工作过程.提出了一种圆度误差测量数据采集系统,该系统采用非接触电涡流传感器作为圆度误差数据的检测元件,采用高速数据采集卡采集圆度误差数据.试验表明,该系统能够满足数据的高速采集要求.     

CNC齿轮测量中心上盘形凸轮测量方法研究

研究了直接在CNC齿轮测量中心上检测凸轮并评定误差的方法和理论。在凸轮工件型面上直接采集测量数据,用三次样条插值函数拟合测头中心轨迹,通过测头半径补偿和凸轮从动轮数据转换,得到凸轮升程曲线,运用最小条件法评价凸轮升程误差。此方法具有测量过程简便、测量效率高、计算精度高、应用性广等优点,适用于以CNC齿轮测量中心为检测设备的自动加工系统。     

基于VB的直线度误差测量软件开发

介绍了直线度误差评定的3种方法,利用Visual Basic软件开发了一套直线度误差测量系统,可自动根据采集到的数据,快速高效地进行分析和误差评定,判断产品是否合格,给出相应的测量结果提示,并将合格数据记录到数据库中,便于产品的追溯,大大提高了测量的效率和准确度。     

锚板二次加工自动定位及控制系统设计

设计了一种锚板二次加工自动定位及控制系统。该系统以数控机床为机械平台,运用机器视觉的方法对锚板圆孔位置进行自动测量,运用容栅传感器对锚板高度进行测量,并基于LabVIEW设计控制系统软件,实现测量数据的采集和处理,同时辅助数控系统对整个自动化加工过程进行控制。实验结果表明:该系统不仅测量精度达到了0.06 mm的要求,而且提高了加工效率,消除了人为因素造成的加工误差,达到了现场加工的要求。     

疲劳试验中测控设备力反馈信号采集同步性研究

本文通过对疲劳试验中应变测量设备,采集控制设备中力反馈数据的基本原理及实现方式进行分析,详细阐明影响控制设备采集到的力反馈数据与应变测量设备采集到的控制设备中力反馈数据间同步性的因素,设计虚拟试验对同步性进行验证。结果表明,应变测量设备能够从控制设备中采集力反馈数据,并且采集到的力反馈数据滞后于控制设备采集到的力反馈数据,在给定试验条件下,滞后不大于135ms,满足试验要求。     

轴类零件公差测量实验计算机控制技术的应用

在互换性测量技术实验中,对轴类零件的测量,大多采用百分表等仪器进行手工测量,其缺点是人的视觉误差等因素造成实验数据的不精确.本文介绍了自动测量控制系统的工作原理,采用数据采集系统对被测工件进行自动测量,从而克服了上述缺点.同时,可以对轴类零件圆周上实现多点测量,能更好地评价轴类零件的几何尺寸.     

轴类零件公差测量实验计算机控制技术的应用

在互换性测量技术实验中，对轴类零件的测量，大多采用百分表等仪器进行手工测量，其缺点是人的视觉误差等因素造成实验数据的不精确，本文介绍了自动测量控制系统的工作原理，采用数据采集系统对被测工件进行自动测量，从而克服了上述缺点，同时，可以对轴类零件圆周上实现多点测量，能更好地评价轴类零件的几何尺寸。     

USB数据采集系统在风压测试中的应用

介绍了基于USB数据采集系统构建风机风压自动测试的方法,同时设计了风压自动测试系统的硬件和软件,实现了风机性能试验中静压和全压的自动采集和处理,现场试验证明该数据采集设备具有测量数据可信,测量精度高,用户接口界面友好,操作方便,扩展灵活等特点.     

圆度误差测量数据的自动采集与处理

在分度头上用测微仪测量圆度误差 ,利用计算机对测量数据进行自动采集与处理 ,其测量和处理精度高 ,速度快 ,操作方便 ,可以近似代替价格昂贵的圆度仪。现简要介绍该系统所用的硬件和软件。     

一种基于工件偏转的激光线扫描误差补偿方法

在激光线扫描测量过程中,外界环境或设备本身等因素会造成测量结果产生粗大误差.因此,为了弥补激光线扫描对目标测量精度的不足,提出了一种基于工件偏转角的激光线扫描误差补偿方法.首先,针对测量系统内的点云预提取问题,提出了目标数据优化获取的技术方案;然后,在光场能量分布的基础上获取对应的位移偏差,进而建立基于工件偏转的误差补...     

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.     

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....     

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。     

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.