差动微位移机构在激光板厚测量中的应用

激光板厚测量系统中,需要动态调节系统中传感器的位置,以适应被测板材表面位置的变化。采用步进电机驱动的差动微位移机构动态地调节系统中传感器位置,实现保证板厚测量有效性和扩展系统的测量范围的目的。应用表明,差动微位移机构能够方便地实现传感器位置的控制,系统的位置调节精度达到0．0025mm。     

基于激光三角法的螺纹量规自动检测系统设计

为实现对螺纹量规大径、小径、中径、螺距、牙型角(牙型半角)等螺纹参数的快速检测,全面反应螺纹实际情况,并提高检测质量、减少检测成本,设计了一种基于激光三角法的螺纹量规非接触式自动检测系统的检测方法.着重研究了该系统基于激光三角检测原理的非接触式检测螺纹量规各参数的设计思路、工作原理和实现方法等内容.设计了由三坐标测量机为位移模块、数控转台为旋转模块、激光位移传感器为检测模块以及控制装置数控处理、控制、评价模块等组成的检测系统,并给出了螺纹主要参数的算法以及数据采集、处理等手段.研制了相应的专用检测软件,进行了相应的实验研究.实验结果表明,该系统能全面反应出螺纹量规实际情况,测试精度高、检测成本低、工作效率高.     

基于激光三角法的零件表面粗糙度在线测量

介绍一种零件表面粗糙度的激光在线测量系统,该系统基于激光三角测量系统,用无衍射激光光束作光源,用高精度的CCD摄像机作位移传感器,通过计算机进行数据处理得到表面粗糙度值。以车削表面为例,用触针法测得的表面粗糙度值和用该系统测得的表面粗糙度值相近,说明实现表面粗糙度在线检测是可能的,该测量方法具有测量速度快和能够显示被测表面的具体形貌等优点。     

高精度时栅转台控制系统设计

为了提高时栅转台控制系统的位置检测精度,提出了一种以卡尔曼滤波和PI控制融合的控制方法,并在此基础上设计了高精度伺服控制系统。该方法利用卡尔曼滤波预测实现PI控制器的参数预测自适应整定,控制系统以则采用以电流环作为内环、位置环为外环的双闭环控制结构和时栅传感器为转台位移反馈部件,同时,以ARM(LPC2124)为控制核心,结合电源电路、SP3232串口通信等硬件电路实现卡尔曼滤波和PI控制相融合的控制方法。经实验测试,设计的时栅转台伺服系统具有运动稳定可靠性,位置检测精度在-0.8″～1.2″范围内, 满足高精度时栅转台控制系统的精度要求。     

基于时序驱动的静态光场式时栅传感方法研究（英文）

提出了一种用时序驱动光敏元构成匀速扫描坐标系的方法,实现了将被测物体空间位移的测量转换为对时间差的测量。根据时栅相对运动双坐标系的转换原理,将线阵CCD的光敏元视为匀速扫描坐标系,两个空间上并排,时序上互相错开的线阵CCD为静止坐标系,则同一被测对象在两个CCD上输出电信号的时间差的变化量与扫描速度的乘积,即为所测位移的大小,并可以判断位移的方向。用雷尼绍激光干涉仪对所研制的CCD时栅传感器进行校准,在有效测量范围(600.05 mm)内,经过修正后的测量误差控制在±2μm以内,实现了在光学领域应用时间测量空间的思想。     

高精度时栅转台控制系统设计（英文）

为了提高时栅转台控制系统的位置检测精度,提出了一种以卡尔曼滤波和PI控制融合的控制方法,并在此基础上设计了高精度伺服控制系统。该方法利用卡尔曼滤波预测实现PI控制器的参数预测自适应整定,控制系统以则采用以电流环作为内环、位置环为外环的双闭环控制结构和时栅传感器为转台位移反馈部件,同时,以ARM(LPC2124)为控制核心,结合电源电路、SP3232串口通信等硬件电路实现卡尔曼滤波和PI控制相融合的控制方法。经实验测试,设计的时栅转台伺服系统具有运动稳定可靠性,位置检测精度在-0. 8″～1. 2″范围内,满足高精度时栅转台控制系统的精度要求。     

基于Matlab与MotoSim EG的涡轮叶片数据处理及检测分析

建立了MH00005-E00机器人的D-H坐标系及运动学模型,在Matlab环境下编写了机器人逆运动学方程求解代码,并对提取的涡轮叶片特征点进行了特定算法的数据处理,实现了机器人末端装载的激光位移传感器始终与叶片型面垂直且数据的坐标姿态在激光位移传感器指定的测量范围内。编写了机器人能够识别的JOB文件代码,在Moto Sim EG环境下搭建了涡轮叶片检测平台,通过导入JOB文件,实现了涡轮叶片的检测,并分析了检测结果。     

基于时序驱动的静态光场式时栅传感方法研究

提出了一种用时序驱动光敏元构成匀速扫描坐标系的方法，实现了将被测物体空间位移的测量转换为对时间差的测量。根据时栅相对运动双坐标系的转换原理，将线阵CCD的光敏元视为匀速扫描坐标系，两个空间上并排，时序上互相错开的线阵CCD为静止坐标系，则同一被测对象在两个CCD上输出电信号的时间差的变化量与扫描速度的乘积，即为所测位移的大小，并可以判断位移的方向。用雷尼绍激光干涉仪对所研制的CCD时栅传感器进行校准，在有效测量范围(600.05 mm)内，经过修正后的测量误差控制在±2 μm以内，实现了在光学领域应用时间测量空间的思想。     

波纹板焊缝跟踪激光传感器的性能研究

采用一种空间漫反射激光测距传感器,研究了波纹板倾斜角与测量结果的关系。在保证被测面上激光光点与传感器之间距离不变的条件下,对不同倾斜角的被测面进行了激光测距试验,并利用Phong光照模型解释了倾角对试验结果的影响。随着被测面倾角增加,传感器测量结果的偏差增大;当倾斜角小于45°时,测量结果的偏差在0.5 mm以内;当倾斜角大于45°时,测量结果的偏差大于0.5 mm。研究结果表明,该激光传感器可以用于检测不大于45°的波纹板,能够满足其折线焊缝跟踪的精度要求。     

大型管件自行式挠度检测系统设计及误差分析

针对大型直缝焊管的挠曲特点设计了自行式挠度检测系统。系统中以遥控小车作为激光三角反射式位移传感器的载体,在框架式的运行轨道上对焊管进行自动测量;系统测量程序以虚拟仪器LabVIEW为软件平台,实现数据采集、输出和显示。通过多组实验,分别分析了激光位移传感器、数据传输线、遥控小车及运行轨道的粗糙度等因素对检测系统的影响,并通过对标准件的测量,得到自行式检测系统的整体误差为±0.5mm。该检测系统满足工业需要。     

Automated laser scanning system for reverse engineering and inspection

Recently, laser scanners have been used more often for inspection and reverse engineering in industry, such as for motors, electronic products, dies and molds. However, due to the lack of efficient scanning software, laser scanners are usually manually operated. Therefore, the tasks that involve inspection and reverse engineering processes are very expensive. In this research, we propose an automated measuring system for parts having a freeform surface. In order to automate a measuring process, appropriate hardware system as well as software modules are required. The hardware system consists of a laser scanning device and setup fixtures that can provide proper location and orientation for the part to be measured. The software modules generate optimal scan plans so that the scanning operation can be performed accordingly. In the scan planning step, various scanning parameters are considered in the generation of optimal scan paths, such as the view angle, depth of field, the length of the stripe, and occlusion. In the scanning step, the generated scan plans are downloaded to the industrial laser scanner and the point data are captured automatically. The measured point data sets are registered automatically and the quality of point data is evaluated by checking the difference between the CAD model and the measured data. To demonstrate an automated measuring system, a motorized rotary table with two degrees of freedom and a CNC-type laser scanner with four degrees of freedom are used.     

三维激光球杆仪的研制与仿真

针对利用激光跟踪仪对数控加工中心进行线性测量成本过高的问题,开发了一种三维激光干涉球杆仪。利用激光干涉法实现距离测量,设计全新测量光路,并通过伸缩杆的被动拉伸实现跟随测量。采用双球铰运动副为激光器的空间姿态调整提供保证,并搭配激光器、镜组微调等装置实现随时对光。利用ANSYS Workbench软件对装置进行建模并验证模型精度。建立机构运动学方程,利用MATLAB对运动空间进行仿真。通过实验验证激光光路,证明了该设计的可行性。     

河床模型地形的无接触快速测量技术

针对河床模型地形测量的需要，介绍了两种无接触快速地形测量技术，即利用超声波实现水下地形无接触快速扫描测量和利用激光与CCD光学成像原理实现水上地形的无接触快速测量，并介绍了测量系统的组成、工作原理及有关主要技术问题的解决方法。     

Geometric and quasi-static thermal error compensation for a laser digitizer equipped coordinate measuring machine

An emerging trend in dimensional inspection of manufactured parts is the use of coordinate measuring machines (CMMs) equipped with non-contact laser digitizers instead of traditional contact probes. Error mapping is generally proprietary to the CMM controller, and the accuracy of such a combined system is limited by the lack of integrated CMM/laser digitizer error compensation. This paper reports progress towards achieving such a system.Geometric error compensation measurements are made on a test machine at 20, 25 and 30 °C. Performance of the system was tested by measuring a special optically coated sphere ballbar artifact. The scan coordinates, the CMM axis scale positions and temperature were recorded simultaneously in real time. The CMM error compensation data was then used to post process the laser digitizer coordinates to obtain improved global part coordinates.Inclusion of the error compensation terms is shown to reduce the dispersion of results by 65 to 80%.     

A Laser Interferometric System for Measuring Arbritrary Angles

A laser interferometric system for measuring arbitrary angles has been developed. The system comprises a two-stage precise rotary table, an adjustable optical polygon, a laser interferometer for measuring constant angles, a frequency optically six-multiplied differential laser Interferometer for measuring small angles, and a CCD-microcomputer-based interferometric signal processing system. The Interference phenomena occuring in the cases of different constant angles with differently oriented incident beams, the method of angle tracking and the method of determining the equivalent parameters of the laser interferometer for measuring small angles are discussed in this paper.Experiments show that this system gives an accuracy better than 0.3 arcseconds in measuring arbitrary angles ranging from 0 to 360 degrees. High accuracy, self-calibration ability, new measuring principles, convenience in use, and low cost are the distinguishing features of this system.     

滚动直线导轨型面测量的误差分析与试验验证

为实现对导轨型面的快速自动化测量,研究一种基于激光三角位移传感器测距的检测方法,提出离散性测量滚动直线导轨副导轨型面精度的测量方法。该方法通过激光三角位移传感器扫描直线导轨各个截面轮廓,设计相应算法对截面轮廓数据进行处理,并分析补偿测量过程中产生的误差,计算导轨截面轮廓滚道的圆心坐标和半径,以此取得直线导轨滚道半径、滚道中心轴线间的距离及滚道中心轴线相对导轨基准面的平行度。最后设计了标准圆棒的测量试验和直线导轨横截面测量试验,对比分析测量结果,验证直线导轨型面精度检测方案的可行性和稳定性。     

Radial error measuring device based on auto-collimation for miniature ultra-high-speed spindles

This study has developed a radial error measuring device for miniature ultra-high-speed spindles because it is very difficult to measure the radial error motion of miniature ultra-high-speed spindles by the conventional measurement method using capacitive-type displacement sensors. The authors have proposed an optical measurement method based on auto-collimation, which evaluates the radial error motion according to the movements of a laser beam reflected from a target sphere attached to the spindle end. This optical measurement method is suitable for radial error measurements of miniature ultra-high-speed spindles because of its applicability to a small target sphere, high-speed response and minor susceptibility to electric noise. In this paper, the measurement principle, and basic characteristics of the optical measurement method in addition to an approximate analysis are shown. The radial error motion of a miniature ultra-high-speed spindle with a steel ball 1 mm in diameter are measured by an optical measuring device designed and manufactured to implement the proposed method. The measurement results show that the optical measuring device is able to measure the radial error motion of ultra-high-speed spindles with a maximum rotational speed of 200 krpm.     

基于激光三角法的自由曲面零件测量

针对超细长螺旋曲面工件廓形误差脱机测量所用测量设备不能满足工件长度和工件稳定旋转等方面要求的难题,提出了一种基于激光三角法的自由曲面零件测量系统,该系统通过利用机床对工件的定位、夹紧、支撑以及有关运动和控制机构,增配激光检测系统,增配运动部件实现的。构建完成了在机激光检测硬件技术平台;通过对采集所得的点云数据进行分析处理,绘制出被测工件的截面廓形。结果表明:该系统提高了检测的效率和准确性,提高了细长螺旋曲面零件的精度,从而实现了螺旋曲面廓形的精确测量。     

用CCD图像传感器测量杨氏弹性模量的研究

对传统的镜尺法测量杨氏弹性模量进行了改进,用高灵敏度电荷耦合器件(CCD)图像传感器取代传统的依靠人眼从望远镜读数获取激光位移数据,实现了过程自动化,消除了测量过程中人为因素的影响。试验测得杨氏弹性模量的相对误差仅为0.88%,大大提高了测量精度。     

灰铸铁激光熔覆铁基和镍基粉末的比较*

采用高功率横流CO2激光器,以铁基和镍基合金粉末为熔覆材料,用同步送粉法在灰铸铁基体材料上进行激光熔覆试验,并对熔覆层组织和性能进行比较分析。结果表明,激光熔覆镍基时覆层内的组织较铁基合金熔覆层组织均匀细致;熔覆镍基和铁基粉末合金层与基体结合紧密成冶金结合;结合区的组织晶粒细小,合金碳化物含量高,其硬度也最高。用正交试验法分析激光功率、扫描速度、熔覆层数对熔覆效果、表面硬度的影响规律,获得激光熔覆层表面硬度显著提高;对表面硬度影响最大的因素是扫描速度,其次是激光功率,熔覆层数则影响不大。熔覆Fe35合金粉末综合优化参数为扫描速度300mm/min、激光功率4.0kW、熔覆二层。熔覆Ni20A合金粉末优化参数为扫描速度400mm/min、激光功率4.0kW。