PLC在圆度测量上的应用

为提高外圆圆度的测量精度，介绍了采集实际轮廓圆的逐点数值的方法。与基准圆进行比较、使用可编程控制器对数据进行最小二乘法处理后，得到的测量数据，比常用测量方法更精确，同时大大提高了圆度测量仪的测量速度。     

光切法扫描测量策略及其数据合成

根据常见测量对象的几何特征及光切法三维轮廓测量特点，设计了两种测量系统结构方案，并重点介绍了四轴卧式系统四种扫描测量策略及其数据台成方法，最后给出了实物测量结果。     

表面轮廓的白光干涉测量法

本文介绍一种采用白光干涉仪进行三维表面形状测量的光学系统。近年来出现了许多不同的方法来分析白光干涉测量法测得的表面轮廓数据。目前还使用许多种商品化的白光表面轮廓测量仪。我们详细介绍了一种组表面轮廓的简单方法,即采用两种简单而有效的算法。这种方法处理数据快速、简单,因而减少了数据搜寻和分析的时间。该系统具有不受限制的理论工作范围,对粗糙和平滑的光学表面进行形状测量。     

表面微观轮廓的非接触测量

一、引言从测量方式来看，表面微观轮廓的测量可分为接触式和非接触式。接触式很难用于起伏的表面轮廓测量。非接触式测量主要以光学方法为代表，如干涉测量法。但是，传统的干涉测量方法（如干涉显微镜）在提供的信息量、信息的可靠性以及提取信息的手段方面都存在一些固有的限制，无法获得表面轮廓曲线，干涉图的到读相当复杂费时，对于无规则条纹无法判断表面凹凸。随着光电技术和计算机技术的发展，在光干涉领域出现了条纹扫描技术、锁相干涉技术、移频干涉技术和相移干涉技术等，为表面轮廓测量新方法的研究，开辟了新的途径。本文介绍…     

基于三坐标测量机的曲面轮廓反向工程数字化测量方法

在三坐标测量机的基础上给出了一种数字化测量曲面轮廓的方法，通过测球半径的补偿、坐标系的建立、最佳测量路径的规划以及混合编程扫描，提高了测量精度及扫描测量的效率，而且采集到的数据可以反映曲面的几何特征，并以实例对该方法进行说明，得到了数字化的曲面轮廓数据。     

基于扫描白光干涉法的接触式轮廓综合测量仪

介绍了一种基于白光干涉原理的接触式轮廓测量仪，该仪器可用于滚动轴承内外圈滚道及滚动体轮廓形貌的综合测量，其理论分辨率可达纳米级，垂直和水平测量范围可分别达5mm和50mm。重点论述了该轮廓仪测量系统的构成、测量原理，并用实例说明干涉信号数据处理过程及结果的有效性。     

钢轨轮廓测量中的车体振动补偿问题研究

采用车载方式进行钢轨轮廓高精度测量,必须进行车体振动补偿.针对车体振动对钢轨轮廓测量带来的误差影响,提出将车体振动分解为同一平面内的平移振动分量和旋转振动分量,对左右股钢轨轮廓数据各个振动分量分别进行补偿.研究了用于钢轨轮廓测量的激光摄像式传感器标定计算方法、车体振动补偿计算方法.给出了基于激光摄像技术的钢轨轮廓测量方案.针对现场钢轨轮廓测量数据检测精度难验证的问题,建议采用钢轨磨耗测量数据验证.研制了基于激光摄像技术和车体振动补偿技术的钢轨轮廓检测装置.每隔100 m共选取10个采样点,分别在人工静态、振动补偿前动态、振动补偿后动态测量钢轨磨耗数据,以静态测量数据为基准,验证振动补偿有效性.结果表明,采用车体振动补偿后,左右股钢轨磨耗测量误差标准差各自减小2.0 mm,测量误差百分比各自减小38.8％、39.7％.选取200 m长线路分别以10 km/h、40 km/h、80 km/h进行钢轨轮廓动态测试,以10 km/h测量数据为基准,验证钢轨磨耗测量数据一致性.结果表明,动态测量钢轨磨耗数据重复性误差均方差控制在0.40 mm以内.     

非球型回转体的内轮廓光电图象测量系统

介绍了一种基于人工视觉的三维内曲面轮廓的光电图象测量系统.该系统由光学测量、激光扫描、计算机图象处理、计算机控制各子系统所组成,用它来对现代工业工程中的非球型回转体曲型零件的内轮廓进行非接触测量,得到所需零件的边缘轮廓和三维内曲面的图象信息.并论述了系统的测量原理、组成和特点.     

测量活塞环外圆轮廓的新方法

提出一种测量活塞环外圆轮廓的方法，介绍了根据该方法研制的轮廓仪的测量方案、仪器结构、误差分析和测试结果。     

广义极坐标法测量渐开线轮廓误差的研究

提出了测量渐开线轮廓误差的广义极坐标方法,导出了测量模型,以此为纽带将展成法与标准极坐标法统一起来;给出了基于简易数控实现该方法的测量原理、测量控制策略以及在法向评定轮廓误差的算式;最后介绍了实测结果。     

全自动微小流量测试仪的研制

针对微小流量难以测量的问题,研制成功了全自动微小流量测试仪用来自动测量通过毛细管的微小流量。该仪器以空气作为工作介质,使用自行研制的以PLC为核心的自动控制系统,间接测试微小流量。本文主要阐述了测试系统的基本工作原理,分析了系统的特性,介绍了仪器的实际物理构造。     

Observation by transmission electron microscopy of etch figures obtained on an organic molecular crystal.

It is interesting to apply the method of etch figures to the study of organic molecular crystal defects, by observing the etch pits as soon as they are produced. We have set up a method to determine the geometrical forms of such small etch pits, observed on pre-shadowed replicas of naphthalene crystal surfaces. The described experimental procedure was designed to avoid artefacts due to vacuum sublimation and moisture traces on the replicated surface. Stereoscopic observation makes interpretation possible. The 3-D morphology and size of etch figures smaller than 1 micron can be determined.     

热轧异型钢材截面尺寸在线检测的三维误差分析

介绍了用光截面法在线检测型材截面尺寸时的三维误差分析,应用摄动法建立了三维误差的数学模型,并进行了仿真计算。根据计算结果及其分析,给出了检测系统测量装置的设计参数。     

大直径钢丝绳直径连续测量方法与装置

研制了大量程的碰头式霍尔位移传感器,采用该传感器测量大直径钢丝绳直径并进行了钢丝绳直径测量装置的结构设计,分析了直径测量的误差产生原因以及减小误差的措施。     

重载滚珠丝杠试验仪的设计

介绍了重载滚珠丝杠试验仪的系统设计,包括系统方案、测量原理和软件流程图等。该试验仪可以动态测量重载滚珠丝杠的反向间隙、摩擦力矩和温升,为重载滚珠丝杠副的优化设计提供实验数据。该系统测量可靠,已经在陕西汉江机床有限公司稳定运行。     

The thickness determination of organic crystals under low dose conditions using electron energy loss spectroscopy.

In the 3-dimensional (3-D) reconstruction of protein crystals with variable thicknesses the electron images and diffraction patterns can only be merged if the crystal thickness is known. Measurement of the thickness using the ratio of the number of inelastically scattered electrons to the number of electrons in the zero loss peak can be accomplished with parallel electron energy loss spectrometry (PEELS). A theoretical analysis of the accuracy of the technique on paraffin crystals of different thicknesses is presented. Our experimental studies with paraffin crystals show the feasibility of measuring a single layer of 47A with good accuracy under low dose and low temperature conditions. A simple experimental apparatus is proposed to obtain thicknesses from small regions of unstained protein crystals prior to collecting the 3-D data sets from the unexposed area of the same crystal.     

The glycosomes of trypanosomes: number and distribution as revealed by electron spectroscopic imaging and 3-D reconstruction

Computer-aided 3-D reconstruction of typanosomes from 0·35-μm-thick sections imaged on the Zeiss 902 electron microscope are being used to study the dynamics of cell organization. Segregation of glycolytic enzymes into glycosomes raises questions concerning the distribution and biogenesis of these organelles. Direct counts of glycosomes from Trypanosoma evansi indicate 30–40 per cell and for the closely related T. brucei, 65 per cell. These figures contrast with the estimates of others who have used model-based morphometric methods to obtain a value of 230 per cell.     

Local collision avoidance of multiple robots using avoidability measure and relative distance

This paper presents a new method driving multiple robots to their goal position without collision. To consider the movement of the robots in a work area, we adopt the concept of avoidability measure. The avoidability measure figures the degree of how easily a robot can avoid other robots considering the velocity of the robots. To implement the concept to avoid collision among multiple robots, relative distance between the robots is proposed. The relative distance is a virtual distance between robots indicating the threat of collision between the robots. Based on the relative distance, the method calculates repulsive force against a robot from the other robots. Also, attractive force toward the goal position is calculated in terms of the relative distance. These repulsive force and attractive force are added to form the driving force for robot motion. The proposed method is simulated for several cases. The results show that the proposed method steers robots to open space anticipating the approach of other robots. In contrast, since the usual potential field method initiates avoidance motion later than the proposed method, it sometimes fails preventing collision or causes hasty motion to avoid other robots. The proposed method works as a local collision-free motion coordination method in conjunction with higher level of task planning and path planning method for multiple robots to do a collaborative job.     

The structure of the developing chick retinal pigment epithelium revealed by high resolution scanning electron microscopy

The retinal pigment epithelium (RPE) in the developing eye of chick embryos has been studied during the early stages of development by high resolution scanning electron microscopy (HRSEM). Specimen preparation techniques which involve removal of the cytoplasmic matrix permitted visualization of organelles and other subcellular structures within RPE cells in detail and in three dimensional (3-D) stereo HRSEM. Using this technique, we were able to examine changes in melanosome structures during development and demonstrate that pigmentation in the RPE was present by day 4 of development. RPE plasma cell membranes showed extensive folding of the apical portion of the membrane closest to the developing neural retina by day 9. Examination of RPE photoreceptor junction revealed photoreceptor inner segments by day 6 and an outer segment by day 9. Mitochondria in the RPE were found to contain tubular cristae only. The ultrastructure in 3-D of the Golgi apparatus, smooth and rough endoplasmic reticulum, lysosomes and nuclear chromatin of the RPE, and Bruch's layer was revealed by the HRSEM method.     

Effects of brefeldin-A on Golgi morphology in human cultured fibroblasts observed in three-dimensional stereo scanning electron microscopy

Brefeldin A (BFA) has been reported to cause disassembly of the Golgi. We have used three-dimensional (3-D) high-resolution scanning electron microscopy (HRSEM) to investigate these effects in human skin fibroblast cells. The spontaneous reassembly during prolonged exposure to BFA and some effects of forskolin were observed. A BFA concentration of 5μg/ml caused Golgi complexes to become vesicular, resulting in a progressive decrease in the size of the Golgi. Morphologic changes were visible within 2 min of BFA incubation, and by 30 min no identifiable Golgi could be found. Spontaneous reassembly of the Golgi apparatus upon the removal of the BFA or with continued long-term exposure with BFA could not be confirmed. Preliminary experiments with forskolin were not effective in reversing or inhibiting the effects of BFA in human fibroblast cells grown in culture. This inability for spontaneous reassembly and nonreversal by forskolin may reflect a differential effect of BFA in various cell types. HRSEM has proven to be useful for observing 3-D morphologic effects of BFA in Golgi.