巧妙测量环型槽孔尺寸的方法

测量环型槽孔通常采用卡钳或带表卡钳测量，但这种方法有一定的局限：当环型槽内孔尺寸小、深卡钳无法测量时通常采用解剖工件的方法来测量尺寸，最后由加工设备保证，费工、费时、成本高。文中采用新方法测量环型槽，不需解剖工件，大大缩短了测量时间，提高了加工效率，降低了成本。     

基于柱面轮廓反求工程的数字化测量及数据处理

柱面轮廓的数字化测量及数据处理是其反求工程的关键技术，将直接影响曲面重构的精度。采用了接触式测量方式获取工件数据。这种测量方式配合测量软件可快速准确地测量出物体的基本几何形状，如面、圆、圆柱、圆锥、圆球。针对复杂曲面的数字化测量和数据处理，提出了建立形状不规则零件测量坐标系的新方法和最佳测量规划，对测量数据进行高精度的处理，得到了反求工程中曲面重构的“点云”数据。     

一种面向航天器装配的测量工艺模型构建技术研究

数字化测量技术与航天器装配技术的融合是实现航天器产品全数字量、高精度、高效率装配的关键技术之一。针对航天器产品装配过程中的测量工艺需求，提出了一种面向航天器装配的测量工艺模型构建方法。将待测特征、基准信息、公差信息、测量设备等与航天器装配过程中测量实施相关联的测量信息组织在一起，形成测量工艺模型。以测量工艺模型为核心，可以促进协调指导各部门实施测量工作，服务于航天器产品的高精度装配。以此模型为基础，开发测量模型构建原型系统，以典型航天器部件进行应用验证，验证了系统的有效性和可行性。     

基于磁阻原理非接触式位移测量的非线性方法

针对低功耗和非接触式位移测量的应用需求，利用磁阻传感器，本文在传统的线性测量方法的基础上，提出了一种非线性的测量方法。设计了一个测量系统，实测结果表明该方法测量精度高、测量范围广、简单易用，也节省了成本。     

数控机床在机测量系统最佳测量区确定方法

为研究面向不同测量对象且具有普适性的数控机床在机测量系统最佳测量区确定方法，选择球作为测量对象，分析了在机测量系统的工作原理及误差来源，利用BAS-BP神经网络建立了单项几何误差白化模型，同时建立了测量系统综合误差模型和球测量误差模型。研究了用于确定最佳测量区搜索寻优的差分优化布谷鸟（DE-CS）算法，进行了不同算法搜索性能对比，确定了算法最优性能参数。搭建了确定球最佳测量区的实验装置，进行了相应实验，对比了利用算法确定和实际测量得到的最佳测量位置的一致性。实验结果表明，利用上述方法搜索计算确定的面向球最佳测量区位置与实验测量确定的最佳测量区位置一致，最佳测量区为：430.783mm≤X≤439.783mm,-145.133mm≤Y≤-136.133mm和-268mm≤Z≤-258mm，实测最大误差最小值为3.1μm，算法求解的误差也为整个测量空间的最小值0.710 7μm，且可用于面向点、面等其他测量对象的最佳测量区确定，具有普适性，可用于确定在机测量系统的最佳测量区。     

浪形保持架整形工序测量方法的改进

针对浪形保持架整形工序中，使用游隙夹具测量径向游隙时，存在测量过程繁琐、时间长、效率低等问题，通过改变模具结构、改进测量方法、采用中心径测量，取代了径向游隙测量，提高了工作效率。     

起重机轨道测量方法和技术发展

传统的起重机轨道测量存在精度低、劳动强度高、安全性较差等缺陷，近年来国内外有很多学者及检验机构针对这一问题展开了深入研究，提出了各种方案，并研制了相应的起重机轨道测量装置，有力推动了轨道测量技术的发展。文中选取几种典型的起重机轨道测量装置及相关技术进行了探讨，分别阐述了基于全站仪及激光准直系统的测量装置和原理，对不同类型测量装置的特点进行了对比分析。在轨道测量相关技术中，介绍了基于机器视觉的架构式轨道检测系统及基于Bertrand模型的图像亚像素边缘定位算法。在上述基础上提出了以激光准直测量平台为基础，结合光斑中心定位及轨道轮廓规划的方案，克服测量小车行走姿势影响测量精度的缺点，避免了小车防侧翻等机构的设计及复杂调试，并有效提高了轨道的测量精度。     

一种敏捷二维测量装置的研究

本文阐述一种新型敏捷测量装置的研究设计过程、提出一种新的测量方法。把敏捷技术应用于测量领域，实现了地、敏捷测量，突破传统测量装置的被动性、局限性，使测量和控制成为一体，提高了测量效率。并且本文从理论上推导出系统数学模型，为实验研究提供了理论指导。     

紫外光电探测器高精度线性测量装置

基于双光阑法，研制了一种紫外光电探测器高精度线性测量装置，主要由高稳定钨带灯、带有快门的双光阑屏、石英透镜、紫外光栅双单色仪和计算机组成，测量波长范围为200-400nm.给出了该装置的原理、测量方法及数据处理方法。测量过程由计算机配套专用软件进行自动控制。利用该线性测量装置，对光电倍增管探测器进行了线性测量。实验结果表明：该装置测量精度高、速度快，测量不确定度小于O．05％，可应用于对精度要求高的紫外光电探测器线性度的测量。     

平面光学零件最小焦距的测量

提出了一种用自准直显微镜和平行光管物镜来测量平面光学零件最小焦距的方法。介绍了测量原理、测量装置，讨论了测量误差。可以看出，本方法所用仪器简单，测量精度较高，适合于光学车间检验。     

Repetitive Measurement and Compensation to Improve Workpiece Machining Accuracy

Achieving workpiece high accuracy at low cost is one of the greatest challenges in the manufacturing industry. A repetitive error measurement and compensation scheme to improve the workpiece diameter accuracy for machining centres is des-cribed. The scheme entails an on-machine measurement and error compensation technology between machining processes. The workpiece diameters are measured along the workpiece length by using a fine touch sensor. The workpiece diameters in the compensation program are modified for implementation of next pass error correction. The technology is realised on a CNC turning centre. This method works well in hard machining and turned workpieces with large length–diameter ratios where the machining process induced errors are significantly greater than errors from other sources. It demonstrates that the work-piece can obtain maximum possible machining accuracy by this repetitive measurement and compensation technique.     

On the workpiece setup optimization for five-axis machining with RTCP function

Nonlinear errors in five-axis machining process are caused due to the nonlinear motions of the rotational axes, which are inevitable. For the RT-type machine tool, the workpiece setup location on the working table has a direct effect on the nonlinear errors, thus there must be an optimal setup position which can reduce the nonlinear errors. Today’s five-axis machine tools are mostly equipped the with the RTCP (rotational tool center point) function, with which the NC program becomes independent from the workpiece setup. In this paper, we have focused on finding the optimal workpiece setup for the RT-type machine tool with RTCP function, more specifically, the Mikron UCP 600 five-axis machine tool in our lab. The kinematics of the machine tool is briefly analyzed. Based on that, the nonlinear error evaluation method with RTCP interpolation is derived. With this method, nonlinear errors can actually be considered as a function of the workpiece setup position. Then, the particle swarm optimization (PSO) is applied to find the optimal workpiece setup, in which a mutation operation is used since PSO traps into local optimum easily. The proposed optimal workpiece setup method is implemented and tested. Example results show that the optimal setup with least nonlinear errors can be found. Some interesting results also show that the nonlinear errors are not sensitive with the z component of the workpiece setup vector. The proposed optimization is nearly zero-cost and easy to both understand and implement, yet has a potential to reduce the nonlinear errors and thus to improve the accuracy of five-axis machining.     

Steady state errors transferred to the turned workpiece

Even if tool and workpiece are set correctly, several errors transfer to the turned workpiece owing to the inherent sources of inaccuracy of the processing system. An evaluation of such errors showed that they partially transfer to the turned workpiece. The ratio of transferred to introduced errors depends upon the ratio of the tangential to the radial compliance of the system.     

Prioritization analysis and compensation of geometric errors for ultra-precision lathe based on the random forest methodology

Geometric errors remarkably affect the dimensional accuracy of parts manufactured by ultra-precision machining. It is vital to consider the workpiece shape for the identification of crucial error types. This research investigates the prioritization analysis of geometric errors for arbitrary curved surfaces by using random forest. By utilizing multi-body system (MBS) theory, a volumetric error model is initially established to calculate tool position errors. An error dataset, which contains information of 21 geometric errors, workpiece shape, and dimensional errors, is then constructed by discretizing the workpiece surface along the tool path. The problem of identifying crucial geometric errors is translated into another problem of feature selection by applying random forest on the error dataset. Moreover, the influence extent of each geometric error on the dimensional accuracy of four typical curved surfaces is analyzed through numerical simulation, and crucial geometric errors are identified based on the proposed method. Then, an iterative method of error compensation is proposed to verify the reasonability of the determined crucial geometric errors by specifically compensating them. Finally, under compensated and uncompensated conditions, two sinusoidal grid surfaces are machined on an ultra-precision lathe to validate the prioritization analysis method. Findings show that the machining accuracy of the sinusoidal grid surface with crucial geometric error compensation is better than that without compensation.     

Modeling and compensation technology for the comprehensive errors of fixture system

Error modelling and compensating technology is an effective method to improve the processing precision.The position and orientation deviation of workpiece is caused by the fixing and manufacturing erro...     

Machining fixture layout design using ant colony algorithm based continuous optimization method

In any machining fixture, the workpiece elastic deformation caused during machining influences the dimensional and form errors of the workpiece. Placing each locator and clamp in an optimal place can minimize the elastic deformation of the workpiece, which in turn minimizes the dimensional and form errors of the workpiece. Design of fixture configuration (layout) is a procedure to establish the workpiece–fixture contact through optimal positioning of clamping and locating elements. In this paper, an ant colony algorithm (ACA) based discrete and continuous optimization methods are applied for optimizing the machining fixture layout so that the workpiece elastic deformation is minimized. The finite element method (FEM) is used for determining the dynamic response of the workpiece caused due to machining and clamping forces. The dynamic response of the workpiece is simulated for all ACA runs. This paper proves that the ACA-based continuous fixture layout optimization method exhibits the better results than that of ACA-based discrete fixture layout optimization method.     

矩形花键滚刀法向齿形的圆弧参数优化

根据平面啮合原理 ,由已知的滚刀圆弧齿形 ,推导出与其共轭的工件齿形方程。通过对工件齿形误差的分析 ,根据最大误差最小法的基本原理 ,对矩形花键滚刀法向齿形的圆弧参数进行优化 ,使滚刀加工出的工件齿形误差最小     

基于GSK980TA数控系统工件坐标系的建立与刀具补偿

介绍了两种基于GSK980TA数控系统建立工件坐标系的方法和对刀具进行补偿的方法。建立坐标系方法之一是用试切法建立工件坐标系,方法二是使用回机械零点对刀的方法建立工件坐标系。此外还介绍了日常使用中解决磨损等造成的误差的方法即刀具补偿的方法。介绍的坐标系建立方法和刀具补偿量的设定方法可直接用于GSK980TA系统控制的车床,对其它数控机床工件坐标系得建立和刀具补偿也有一定的参考意义。     

一种过定位下工件定位误差的计算

提出了计算“4-2-1”过定位下工件定位误差的方法，考虑了两个条件：一是定位件与工件不发生干涉，二是保证工件放置的稳定性。根据以上两个条件，把“4-2-1”过定位下工件定位误差的计算分为五个具体的步骤，最后举例说明了本方法的实用性。     

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.