全自动测量轴圆度的V形法测量系统研究

为了寻找一种结构简单、精度高、造价较低而且能全自动地测量轴圆度的方法,本文根据一般V形法的实际应用及测量精度,对一般的V形法测量系统进行了全自动化研究.本文介绍了V形法的测量原理、数据处理方法、全自动V形法测量系统的研究以及主要单元部件的构成.通过计算机控制、直流伺服电机带动被测轴旋转、计数码盘计算被测轴转过的角度、测微头自动拾取测量数据、计算机计算并输出计算结果,能够实现全自动测量轴的圆度,测量精度可达到十纳米级.     

A comprehensive technique for measuring the three-dimensional positioning accuracy of a rotating object

A method for measuring the accuracy of rotating objects was studied. Rotating axis errors are significant; such as the spindle error of a machine tool which results in increased surface roughness of machined work pieces. Three capacitance-type displacement sensors were used to measure the position of a rotating master ball. The sensors were mounted at the three orthogonal points on the spindle axis. The measurement data were analysed for rotating spindle accuracy, not only for the average roundness error but also for the spindle volumetric positional error during rotation. This method is simple and economical for industrial field use for regular inspection of spindles using portable equipment. The time taken for measurement and analysis using this method is only about two hours. This method can also measure microscopic amplitudes in 3-D directions of vibrating objects.     

Development of an automatic cumulative-lead error measurement system for ballscrew nuts

Ballscrew is a precision mechanical component used to convert rotational motion to linear motion in the precision linear stage. The precision measuring system for the screw's cumulative-lead error is already well known. Up to now, however, there is no suitable measuring equipment for internal cumulative-lead error of the nut. For a matching pair, it is not reasonable to understand the quality of only one piece. This paper presents a developed automatic cumulative-lead error measuring system for ballscrew nuts. The nut is clamped by a rotational stage, in which the moving angle is detected by a rotary encoder. The probing ball is inserted into the nut and remains in contact with the thread groove of the nut. The probe arm is mounted on a linear slide so that when rotating the nut, the probing ball will be pushed by the groove wall and moved axially. A high-resolution diffraction scale is employed to detect the linear movement of the probe to nanometer resolution. Combining the angular and linear motions, the cumulative-lead error of the nut can be realized. In practice, however, the nut will cause typical spindle errors during rotating, including axial slip, radial run out, and tilt motions. These errors have to be compensated in order to guarantee the accuracy of measurement results. A multi-sensor error compensation system is thus developed. Experimental results show the applicability of this developed measuring system.     

激光制导测量机器人几何误差分析

目的: 为了实现对工件进行自动高效地测量,建立了激光制导测量机器人系统,研制了测量机器人样机。对测量机器人的光靶自动跟踪装置旋转轴偏心误差和光靶与两轮中心连线误差进行了研究。方法:首先,介绍了基于“光束运动-光靶跟踪”理论的激光制导测量机器人技术和原理。接着,根据系统原理,研制了实验样机,并给出其理想的几何关系。然后,推出了旋转轴偏心误差和光靶与两轮中心连线误差几何误差数学模型。最后,利用三坐标测量机与激光制导测量机器人系统对样机进行了比对实验。结果：实验结果表明：光靶中心偏离理想位置的误差（x轴）为0.13mm。结论：对激光制导测量机器人移动反馈控制系统的设计和实现具有指导性作用。     

火箭喷管运动视觉测试精度的校准与实验

基于新型双轴摇摆直线升降运动校准装置,提出了一种喷管运动视觉测量系统的校准方法。首先,将校准装置提供的摆心、摆角的标准值与视觉测量系统的测量值在空间上对应起来,通过校准装置提供给喷管模型2次不同轴的摆动,推导出视觉运动测量系统的世界坐标系与喷管摆角坐标系之间的位姿关系。然后求解出二者位姿矩阵和平移向量,在视觉运动测量系统中建立喷管的摆角坐标系;通过时间同步系统向校准装置和视觉运动测量系统发送同步时间基准信号和同步触发信号,同步二者的采样时间,实现标准值与测量值在时间上的对应关系,完成摆动动态数据的直接比较。最后对喷管运动视觉测量系统进行了校准实验,分析了喷管在±12°的摆动空间内不同位置的摆心、摆角的测量误差。实验结果表明,在运动范围内摆角的最大测量误差为0.093°,摆心的最大测量误差为0.832mm。     

Geometric error measurement and compensation for the rotary table of five-axis machine tool with double ballbar

This paper proposes a novel measuring method for geometric error identification of the rotary table on five-axis machine tools by using double ballbar (DBB) as the measuring instrument. This measuring method greatly simplifies the measurement setup, for only a DBB system and a height-adjustable fixture are needed to evaluate simultaneously five errors including one axial error, two radial errors, and two tilt errors caused by the rotary table. Two DBB-measuring paths are designed in different horizontal planes so as to decouple the linear and angular errors. The theoretical measuring patterns caused by different errors are simulated on the basis of the error model. Finally, the proposed method is applied to a vertical five-axis machining center for error measurement and compensation. The experimental results show that this measuring method is quite convenient and effective to identify geometric errors caused by the rotary table on five-axis machine tools.     

Analysis of eccentricity in the ball bar measurement

The ball bar is widely used in machine tool measurement because it is convenient and cost effective. Eccentricity exists due to machine errors and installation errors during a ball bar test, and the coordinate transformation method is used to remove eccentricity. However, distortion of data (i.e., ovalization) becomes large when eccentricity relative to the radius of a circle cannot be ignored. The number of sampled data for the total angle of circular path is used to estimate the actual rotating angle of the ball bar during measurement. To prevent distortion of data, actual rotating angles of the ball bar must be estimated exactly. In this paper, geometric relations of the ball bar measurement model are described based on the poses of two reference coordinate systems (ball bar and nominal coordinate system). The proposed algorithm calculates the actual rotating angle of the ball bar using geometric conditions and removes eccentricity through coordinate transformation.     

Complex wear measurement on thin coatings by the cratering method

Ball cratering and rotating wheel tests are useful techniques for abrasive wear resistance evaluation of thin coatings. Nevertheless, such techniques involve significant experimental errors, coming from equipment deficiencies and changes in wear response depending on test parameters. In case of rotating wheel test, common instrumental errors are: geometry‐induced errors (curved or non‐horizontal sample surface), alignment errors (misalignment between ball/wheel rotation axis and sample stage) and optical measurement errors. In the present paper, errors due to crater dimension detection system (penetration depth or crater diameter) and equipment deficiencies (rotating axes misalignment and sample slope) were numerically analysed. A general expression for volume calculation was obtained, considering axes misalignment and sample slope, and experimentally validated by wear tests on Ti/TiN CAE‐PVD coatings and profilometer abraded volumes measurement. Results showed that axes misalignment and sample slope involve considerable errors in wear coefficient evaluation. However, errors can be corrected by the use of obtained expressions. Copyright © 2009 John Wiley & Sons, Ltd.     

透镜组中心偏自动测量

中心偏的自动化测量避免了人为测量误差,提高了测量精度,为提高仪器的光学质量提供了依据。在介绍了反射式中心偏测量的基本原理的基础上,推导了中心偏测量的迭代公式。然后给出了测量系统和光路的设计方案,并对整个系统中关键技术:自动聚焦、指标自准像提取、最佳光轴的拟合,进行了详细的阐述。最后提出了整个系统的误差分析及改进方案。     

精密视觉印刷设备的自标定

为了提高全自动视觉印刷设备的精度,提出了一种简易、有效标定基于三自由度平面并联调整台的视觉丝网印刷设备的算法。首先,分析和标定了视觉测量系统,并通过激光干涉仪验证了结果的准确性。然后,分析了三自由度平面并联调整台的几何参数误差;基于印刷设备自身的视觉测量系统,分步标定了并联平台的动平台坐标系、传动比误差和仅需的部分几何误差源。提出了一种满足全姿态且适应不同制程的三角形面姿态插值方法和纠偏调整算法,从而避免了较为复杂的几何全参数辨识,降低了对调试人员的技术要求。实验结果表明：在并联调整台工作空间内,标定后的最大位置误差从标定前的161.6 μm下降为12.3 μm,最大姿态误差从标定前的2.232″下降为0.720″,基本满足印刷设备对精度的要求。     

往返小车及上卷小车在自动上卷系统中的应用

介绍自动上卷的基本原理与系统组成,描述实现上卷功能的相关设备,分析整个顺序控制过程,详细说明带卷测宽与宽度对中以及带卷高度对中的基本原理与系统组成,给出主要参数的数学模型及计算方法。针对小车运行过程中因车轮的滑移或滑转对编码器测量产生的误差,通过引入防滑链,有效解决上述问题。     

柴油机连杆加工误差综合检测装置设计

介绍了一种柴油机连杆加工误差综合检测装置,它能对不同型号的连杆的尺寸、形状和位置精度进行高精度的自动检测.介绍了检测装置的结构,检测原理和检测方法,建立了评定各项误差的数学模型.由计算机程序软件按选定的误差评定方法对实时采集的数据进行分析处理,实现了连杆的中心距、平行度、垂直度、圆柱度误差的计算机辅助智能检测.     

发动机叶片自动化喷涂转台的设计

为了能够提高工作效率和喷涂质量,设计研制了发动机叶片自动化喷涂转台。该转台设备与ABB喷涂机械手组成了一套自动化发动机叶片喷涂设备。介绍了转台设备的机械结构、设计原理以及电控系统的实现方法。该转台设备在实际应用中取得了很好的效果,可以推广到其他复杂产品的自动化喷涂生产中。     

单体液压支柱三用阀试验自动测控系统

介绍了三用阀自动装卸机构、自动调压装置、液压控制系统的组成和工作原理。在分析单体液压支柱三用阀试验标准和试验功能要求的基础上,采用工业控制计算机、PCI总线的数据采集和控制卡及相应的调理板组成硬件系统。建立了试验参数设置数据库和试验结果数据库,分别用于存储被试阀的信息和技术参数、试验过程中测得的数据及经过计算和判断得到的信息。开发了一套计算机自动测控系统软件,该软件有试验参数设置、全自动试验、硬件诊断、试验数据管理等功能。计算机测控系统控制三用阀试验装置,实现了三用阀的自动装卸、安全阀压力的快速精确调定、试验数据的精确采集和自动生成打印报表等功能。     

ECR等离子源静电探针自动监测系统

ECR等离子源主要由电源系统、抽气系统、供气系统、真空室等设备组成,对于研究型设备,还包括测控部分.传统的测控系统对系统设备大多采用单台测控,人工调节,这样系统效率比较低.该文采用模拟开关切换8路静电探针得到不同位置的等离子体参数,经电荷放大器对弱信号进行放大后显示.该方法在实际使用中取得了较好的效果.     

支持多种通信规约的RTU仿真测试系统

本文介绍了一种支持多种通信规约的RTU仿真测试系统，只需在被测试的RTU前使用该测试系统，就能方便测试使用多种通信规约的RTU能否正常工作，减少了新建厂站投入使用的调试时间。它还可以广泛用于电力自动化设备生产厂家的产品通信功能测试，为发现，分析，解决电力系统自动化设备通信问题提供强有力的分析工具。     

Self-calibration and compensation of setting errors for surface profile measurement of a microstructured roll workpiece

Microstructured roll workpieces have been widely used as functional components in the precision industries. Current researches on quality control have focused on surface profile measurement of microstructured roll workpieces, and types of measurement systems and measurement methods have been developed. However, low measurement efficiency and low measurement accuracy caused by setting errors are the common disadvantages for surface profile measurement of microstructured roll workpieces. In order to shorten the measurement time and enhance the measurement accuracy, a method for self-calibration and compensation of setting errors is proposed for surface profile measurement of microstructured roll workpieces. A measurement system is constructed for the measurement, in which a precision spindle is employed to rotate the roll workpiece and an air-bearing displacement sensor with a micro-stylus probe is employed to scan the microstructured surface of the roll workpiece. The resolution of the displacement sensor is 0.14 nm and that of the rotary encoder of the spindle was 0.15r~. Geometrical and mathematical models are established for analyzing the influences of the setting errors of the roll workpiece and the displacement sensor with respect to the axis of the spindle, including the eccentric error of the roll workpiece, the offset error of the sensor axis and the zero point error of the sensor output. Measurement experiments are carded out on a roll workpiece on which periodic microstructures are a period of 133 i~m along the circumferential direction. Experimental results demonstrate the feasibility of the self-compensation method. The proposed method can be used to detect and compensate the setting errors without using any additional accurate artifact.     

Offline and online strategies to improve pose accuracy of a Stewart Platform using indoor-GPS

The pose accuracy of a robot manipulator may be improved by assessing and correcting systematic errors. Both offline and online strategies can be considered. To date, there has not been a solution for the online pose error correction of parallel manipulators. Moreover, offline strategies using indoor-GPS as reference measurement system have not yet been investigated. In this paper an optimization-based kinematic calibration method and an online correction technique are proposed and implemented for a low-cost Stewart Platform. In both cases, an indoor-GPS system was used as reference measurement equipment. Performance of both strategies are compared to a kinematic calibration method based on direct parameter measurement. Pose errors are evaluated for each strategy using a robotic total station. Performance of the optimization-based calibration and the online correction technique were similar and better than the direct parameter measurement calibration. Both techniques resulted in average pose errors less or equal to 0.3 mm and 0.05°. The proposed strategies may be adapted to other similar parallel manipulators and are applicable to large sized equipment.     

代谢热整合法无创血糖检测技术研究

介绍了一种新的基于代谢热整合法的无创血糖检测技术。采用温度传感器、红外传感器、湿度传感器和光学测量装置,通过测量人体代谢产生的热量、血液流速、血氧饱和度,利用人体代谢产生的热量是血糖浓度、供氧量的函数,可以推算出血糖浓度。介绍了系统的组成、数据处理方法及可能造成误差的因素。用所研制的检测系统进行了临床实验,得到的血糖值与用大型生化分析仪测得的血糖值的相关系数达到0.856。实验证明,代谢热整合法无创血糖检测技术是可行的。     

汽车车轮形状误差的测量和分析

介绍了汽车车轮径向跳动和轴向窜动误差的测量原理和数据处理方法。由计算机控制的半自动测量台,测量及数据处理速度快,精度高,系统性能稳定。