超精密机床激光干涉测量系统误差分析及补偿

详细分析了超精密机床加工中,激光测量系统误差组成及其产生机理,给出了有效的修正和补偿手段.影响激光测量系统精度和重复精度的主要误差因素可分为3类：内部误差、环境误差和安装误差.通过实例分析精密机床四轴激光测量系统,设计出了四轴激光测量光路,实现超精密工作台的X、Y、Rz三自由度位置反馈,给出了影响测量精度的误差因素以及对系统精度的影响大小.     

激光热轧带钢平直度测量仪

本文介绍了一种新的激光热轧带钢平直度测量系统,系统采用多束激光作光源,无需分光扫描和传感器定位装置;优化设计图象检测系统,保证了系统的响应速度;改进平直度计算模型,提高系统测量精度和灵敏度;配合有效的防护措施,成功地研制了ＬＦ—１００型激光板形仪。近十个月的在线测量结果表明,静态测量精度达±０．６５ｍｍ ,带宽５点测量时间达８７ｍ ｓ／次。     

轮胎胎面参数在线检测系统研究及应用

为了提高汽车轮胎生产过程中对胎面尺寸的测量精度,针对移动中的橡胶胎面设计了一种测量轮胎胎面参数的在线检测系统。选用3D激光传感器,根据传感器获得的坐标数据绘出胎面横截面轮廓,基于B样条曲线拟合方法,通过特征点测量计算胎面横截面数据;选用CCD图像传感器,设置两端基准线,根据现场亮度采用可调光源控制器,并采用OSTU算法对图像进行二值化处理,基于像素数和实际的尺寸存在线性对应关系,可获得胎面长度。现场实验结果表明,该测量系统的横截面参数测量精度小于1 mm,长度测量精度小于2 mm,能够满足生产工艺的测量要求,可实现胎面参数的在线动态测量,该测量系统具有安装方便、运行稳定等特点。     

高精度丝杠磨削的新途径

在螺纹磨床上成功地采用了激光反馈自校系统，使 １ｍ长的丝杠的磨削精度稳定在五级以上。     

双频激光三尺组合法直接度测量系统

本文提出一种双频激光三尺组合法直线度测量系统，理论分析及实验结果都说明本系统可望获得优于０．１μｍ／ｍ的精度，是提高现有直线度测量精度的一个较实用的方法。     

基于并联理论的单目视觉位姿估计

搭建了一种主动式测量系统用于测试伺服稳定平台的伺服精度.以此系统为基础,提出了基于并联理论的单目视觉位姿测量方法.介绍了系统的硬件组成和系统测量原理,分析了系统的分辨率.给出了激光点在投影靶坐标系下的计算原理及过程.然后,从并联机构的自由度出发,将视觉测量系统等效地转化为一个并联机构,将视觉测量系统的位姿估计问题转换为并联机构的正解问题.利用并联机构的运动影响系数迭代求解系统的位姿,由并联机构关节螺旋直接得到影响系数,由此简化了推导过程.仿真和实验结果表明:系统的姿态测量精度为±0.05°.该方法能够快速稳定的收敛,基本达到了系统的设计要求.     

双频激光干涉三自由度微振动测量系统

为获取光学平台多自由度微振动信息,设计了一种基于平面镜双频激光干涉的三自由度动态微振动测量系统。该系统利用激光多普勒效应,采用三个测量轴获得测量反射镜的三点位移信息,计算出测量镜平动、扭转角、俯仰角信息,实时检测三自由度的微振动情况,从而为光学系统的微振动补偿控制提供基础。对微振动测量系统进行了不确定度分析,建立了不确定度模型,为进一步提高系统精度提供理论依据,也为系统在校准和计量领域的应用奠定基础。实验过程中,采用高精度地震计对待测平台进行同步测量,与系统平动测量结果进行对比,验证了系统的测量准确性。该系统的平动分辨率可达到5nm,扭转角分辨率为5.05μrad,俯仰角分辨率为4.69μrad,具有多自由度、非接触、高分辨、可溯源的优点。     

城轨车辆车载轨道几何参数检测系统的研制

针对目前城市轨道交通中安装于工程车辆的轨道几何参数检测系统不能真实反映列车实际在途运行时的轨道几何状态问题，研制了基于载客车辆的轨道几何参数检测系统，在列车日常载客行驶的同时，实现对轨向、轨距、水平、高低、三角坑、钢轨断面磨耗等轨道几何参数的实时采集和分析。通过研究基于非接触式激光测量技术和惯性基准测量等技术，载客车上集成安装激光摄像组件及惯性测量组件，实现了钢轨外形轮廓的实时测量及各传感器的姿态跟踪测量。最后通过上位机采集软件实现了原始数据的收集、各个轨道几何参数的合成计算、检测结果报表的自动传输等功能，并在实际轨道线路上进行了各参数的人工设置障碍测试。结果表明：轨距参数检测精度小于0.8 mm，高低参数精度小于或等于1 mm，轨向、水平、三角坑参数检测精度小于或等于1.5 mm，验证了系统检测的准确性；对比分析多趟检测结果，各参数重复精度均小于0.5 mm，验证了系统具有较高的稳定性。     

新型大锻件尺寸在线测量系统的关键技术研究

根据大型锻件制造工艺要求,开发出一套新型的大锻件尺寸测量系统,由球面二自由度并联机构实现激光距离传感器的扫描运动,进行非接触式锻件尺寸测量.建立了基于球面并联机构的测量系统数学模型,根据该模型完成系统的硬件设计和测量软件设计,所得实验结果表明新测量系统可达到较高测量精度.     

基于位置敏感器件的液位检测系统及其数据处理

精确测量光固化成型设备中光敏树脂的液面位置是确保成型精度的关键,根据激光三角法原理设计基于PSD的液位检测系统,采用点激光和一维位置敏感器件组成液位检测系统。通过测量点激光在PSD上的位移量来获取液面位置的变化量,在分析PSD误差特点基础上,通过优化结构设计、信号采集、检测系统标定和实时数据处理4个方面来提高检测精度。实际测试表明:液位检测系统量程中间位置的误差小于0.27%,两边误差小于0.4%,可满足系统测量精度要求。     

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...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

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.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

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.     

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....