数控机床体积定位精度的测量与补偿

介绍一种使用激光多普勒位移测量仪，对数控机床进行体积误差检测的激光矢量测量新方法，该方法可以方便而快速的检测出机床的体积定位精度，包括3个定位误差，6个直线度误差和3个垂直度误差，同时还可以根据测量的体积定位误差数据生成误差补偿的代码，进而可以对其进行体积定位误差的补偿，大幅度提高了数控机床加工精度。     

运用激光测量提高数控机床精度

介绍了激光干涉法测量误差的原理和误差分析方法，对数控机床的定位误差及反向间隙进行测量与补偿，可以显著提高数控机床精度。实验结果表明，本文所采用的方案正确、有效。     

数控机床误差的激光干涉仪自动瞄准测量及补偿技术研究

开发了用于数控机床空间误差测量的激光干涉仪自动瞄准系统。该系统实现了机床多轴联动、而激光束的方向发生连续改变时空间曲线轨迹定位误差的测量。提出了通过一次对光实现数控机床整个空间定位误差的直接测量方法。采用网格方法储存测量误差,用有限元法实现补偿误差的预报。在立式数控加工中心上进行了误差的测量和补偿试验,结果表明所提出的误差测量方法精度高、速度快,误差补偿效果明显。     

HMC1000卧式加工中心按ISO230-6标准检测和G代码补偿

回顾了国际标准ISO-230对数控机床验收的发展过程,介绍了ISO230-6数控机床对角线检测的方法。应用美国光动公司激光多普勒测量仪对数控机床进行3D体积位置误差测量,将检测误差输入数控机床进行G代码补偿,比较了补偿前、后的检测误差,以实例说明了补偿后明显提高了数控机床的整体精度。     

数控机床空间定位误差检测新方法研究

介绍了一种基于激光多普勒位移测量技术的机床几何误差测量辨识新方法,即激光矢量分步对角线测量法.该方法和传统的体对角线测量技术相比较,该方法能够取得3倍的数据,可以方便而快速地检测出机床的体积定位精度,并且能够获得足够的信息用于分离各误差元素,进而可以对其进行体积定位误差的补偿,大幅度提高了数控机床加工精度.     

HMC1000卧式加工中心按IS0230—6标准检测和G代码补偿

回顾了国际标准ISO一230对数控机床验收的发展过程,介绍了IS0230—6数控机床对角线检测的方法。应用美国光动公司激光多普勒测量仪对数控机床进行3D体积位置误差测量,将检测误差输入数控机床进行G代码补偿,比较了补偿前、后的检测误差,以实例说明了补偿后明显提高了数控机床的整体精度。     

数控机床误差测量技术及其误差补偿

介绍了一种使用激光多普勒位移干涉仪对数控机床误差测量和误差补偿的方法。分轴步进体对角线测量法就是通过序列的单轴运动使机床沿着体对角线运动,这样便可以分离出数控机床的各项空间误差元素,包括直线定位误差、垂直直线度误差、水平直线度误差。然后利用测量误差自动生成补偿文件,输入数控系统,对误差进行相应的补偿。实验证明了这种测量和补偿的有效性。     

数控机床定位精度自动螺距补偿功能的应用

目前许多数控机床厂为了提高数控机床的位置精度及降低成本，采用机床数控系统中螺距补偿功能来消除其定位误差。螺距补偿是激光干涉仪通过机床运动部件在被测量轴每1个目标位置上测得的位置误差值，并通过补偿软件计算出位置误差补偿值，然后利用相同的RS232通讯电缆传送给数控系统，实现自动补偿。它比通常的补偿方法节省大量的时间，并且避免了由于手工计算和手动键入补偿值而引起的人为误差，同时可以最大限度地选用被测量轴上的补偿点，使之达到提高数控机床位置精度的目的。     

数控机床定位精度的检测及补偿

首先对数控机床的加工误差来源进行了分析,接着阐述了应用双频激光干涉仪对数控机床定位精度进行检测的方法以及通过补偿机床螺距和对丝杠间隙误差进行补偿的方法,实现了机床线性定位误差的补偿,从而极大地改善了数控机床的定位精度。     

数控机床定位精度的检测及补偿

首先对数控机床的加工误差来源进行了分析,接着阐述了应用双频激光干涉仪对数控机床定位精度进行检测的方法以及通过补偿机床螺距和对丝杠间隙误差进行补偿的方法,实现了机床线性定位误差的补偿,从而极大地改善了数控机床的定位精度.     

三维空间定位精度的高效测量与补偿及校验

介绍数控机床三维空间定位精度测量、补偿和校验的一种高效、精确的方法。通过激光多普勒干涉仪,运用矢量原理和多步测量的方法,通过四次调整测量就可以获得机床的12项误差元素,根据测量出的误差数据可以生成误差补偿代码并用于误差补偿以提高机床三维空间定位精度,最后通过实例验证该测量方法的准确性及高效率。     

A methodology for systematic geometric error compensation in five-axis machine tools

To enhance the accuracy, an efficient methodology was developed and described for systematic geometric error correction and their compensation in five-axis machine tools. The methodology is capable of compensating the overall effect of all position-dependent and position-independent errors which contribute to volumetric workspace. It was implemented on a five-axis grinding machine for error compensation and for the check of its effectiveness. Error compensation algorithm was designed, and a routine was written in Matlab software. The developed technique and software are based on an error table which interprets the function of axis through cubic spline technique and synthesis modeling of a machine tool. Recursive compensation methodology was used to remove the machine errors from the actual tool path and inverse technique was implemented to find the corrected positions of prismatic and rotary joints. Moreover, it can convert the corrected tool paths into practical compensated NC codes. The generated, corrected and modified NC codes directly fed to the controller of a five-axis machine tool. Validation of the technique was preceded by repeated experimentation of measurement and through machining of typical standard workpieces with some additional specific features. Experimental results exhibit effective compensation and remarkable improvement in the parametric and volumetric-workspace accuracy of the five-axis machine tool.     

五轴数控机床万能主轴头空间误差建模研究

五轴机床万能主轴头空间误差建模的传统方法采用齐次变换矩阵(HTM)进行运算,计算过程复杂,物理意义很难理解。提出了一种主轴头空间误差的简化建模方法。综合考虑了主轴头两个旋转轴的运动误差和刀具热误差对主轴头空间精度造成的影响。优化了机床运动坐标系设置,从而降低了空间误差模型的复杂性。基于刚体运动学原理,描述了主轴头的运动误差传递关系。结合实例,推导出了主轴头空间误差的数学表达式,其建模过程简单,物理意义明确。     

Measurement and compensation for volumetric positioning errors of CNC machine tools considering thermal effect

The measurement and compensation of volumetric positioning errors can be used to significantly improve the accuracy of machine tools. In this paper, a sequential step diagonal measurement is introduced to measure nine volumetric positioning errors in a short time. Measurements under various thermal conditions are preformed to understand the relationship between the volumetric positioning errors and the machine temperature field and variations. A radial basis function neural network is used to predict the volumetric positioning errors at all positions based on the temperature distribution of the machine. Compensation experiment is carried out to validate the performance of the measurement and the prediction method. The experimental results show that the volumetric accuracy of the machine tool is significantly improved by the error compensation.     

Dynamic and geometric error assessment of an XYC axis subset on five-axis high-speed machine tools using programmed end point constraint measurements

This paper presents a technique for assessing the volumetric errors on a five-axis machine tool for motion involving two linear axes and one rotary axis at selected feed rates using data from two sources. The first source of data is obtained through a programmed end point constraint procedure with measurement of the 3D volumetric positioning errors between a point on the tool holder and another fixed to the machine table reference frame. The tests involve maintaining the nominal coincidence of these two points whilst exercising the three axes. The second source of data is the position feedback signal from the encoder provided by the machine controller. Tests were carried out at low and high feed rates to evaluate the effect of geometric and dynamic errors. Polynomial functions are used to represent and then predict the geometric errors. The predicted geometric errors are then added to the dynamic errors provided by the servo errors from position feedback signals and propagated to the tool centre point and are compared with the measured volumetric errors. It shows that the influence of the geometric errors are dominant at low feed, whereas the effects of the servo errors of the linear axes become dominant as the feed increases, reaching 80% of the total error at a feed of 10,000 mm/min.     

双转台五轴机床空间误差补偿技术研究

几何误差、热误差和切削力误差占到了机床总误差的75%,对这3项误差进行控制是提高机床加工精度的关键所在。以双转台五轴机床的空间误差作为研究对象,通过对加工位置、主要热源及电动机电流等相关因素进行分析,确定空间误差建模所需的位移变量、温度变量和切削力变量。以现有的多种误差建模方法为基础,通过对信息融合技术进行研究,提出一种机床空间误差的多模型融合预测方法,建立综合反映几何误差、热误差和切削力误差的最优空间误差模型。最后以DSP为核心,设计空间误差补偿器,实施空间误差补偿,验证补偿效果。结果显示,建立的模型预测精度较高,残差小于2μm,而实施空间误差补偿后,加工零件的轮廓误差也由15μm降到了5μm,补偿效果明显。     

三维与三轴校准在机床生产中的差异

在机床的设计中，许多制造者都认为三轴和三维的精度是一样的。而实际上，三轴的精度只有一维，因为它只是用指定公差的线性来测量每个轴。三维的精度，是指线性测量每个轴与X，Y和Z轴的关系。标定三轴的精度是相当简单的，而标定三维的精度则较复杂．但能节省时间，所以，它是一个更好的方法。