FANUC0系统维修知识讲座——第9讲 丝杠螺矩误差补偿的基本原理和补偿方法

一、丝杠螺距误差补偿的基本原理 在半闭环位置控制系统中,从位置编码器或旋转变压器等位置测量器件返回到数控系统中的轴运动位置信号仅仅反映了丝杠的转动位置,而丝杠本身的螺距误差和反向间隙必然会影响工作台的定位精度,所以对丝杠的螺距误差进行正确的补偿在半闭环系统中是十分重要的。 图1描述了丝杠螺距误差补偿的基本原理。     

CNC2190数控龙门铣床螺距误差补偿与重建

对数控机床反向间隙补偿和螺距误差补偿原理及测量方法进行了深入研究和分析,并针对CNC2190数控铣床FANUC 18-M系统的螺距误差进行实际补偿和重建,取得了良好的补偿效果,说明对滚珠丝杠传动机构的反向偏差与螺距误差进行补偿是恢复和提高机床精度的一种重要手段.     

使用激光反馈系统的精密螺纹磨削

作者研究了螺纹磨削获得高精度螺距丝杠的方法。一种使用激光测量螺纹磨床工作台进给误差的闭合补偿系统用于现有磨削系统,大大简化了高精度螺距丝杠的磨削。     

数控系统中螺距补偿的原理与设计

由于数控机床的丝杠在制造、安装上存在误差以及长期使用造成的磨损,导致螺距实际移动值与预期设定值之间存在差异。提出了螺距误差的单向补偿方法和双向补偿方法。介绍了螺距补偿的原理,包括单向补偿方法、双向补偿方法的原理;提供了一种实现单向补偿、双向补偿的设计方案;编写了简单的零件位置移动程序来测试双向补偿方法是否生效。实验结果证明,该方案能够解决数控系统中的螺距误差。     

精密螺纹磨削的研究(第一个报告:螺距误差的起因)

近来,机床和长度测量仪等设备上淬硬和磨削丝杠的使用与日俱增,而且对这些磨削丝杠要求有极高的螺距精度,如已普遍使用在数控机床上的那些丝杠。然而,目前的螺纹磨削技术还不能满足这种要求。基于在螺纹磨削中热变形是螺距误差的主要起因这一设想,本文将讨论工件螺纹和磨床热变形的试验和理论分析。为了达到最小的螺距误差,可按照磨削情况加以补偿。为此,根据作者们的试验,使用了一个数字控制系统的补偿装置。试验结果证明,磨削一米丝杠的全长螺距累积误差降到5微米左右;另外,对设计一台磨削高精度丝杠的螺纹磨床提出了一     

PMAC位置控制系统螺距误差补偿的应用研究

分析了位置控制系统定位精度的影响因素,其中滚珠丝杠副的螺距累积误差是定位误差很重要的一个来源,利用软件补偿法对PMAC位置控制系统螺距误差实施了在线补偿。通过补偿前后系统定位精度的对比分析,螺距误差补偿可以有效提高系统的定位精度。     

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.     

把神经网络应用于丝杠磨削过程的建模与控制

提出了利用两个人工神经网络对丝杠的磨削过程进行建模与预测控制的思想.其中,网络1用于复映传动链、热变形和力变形等误差源与工件螺距误差的关系,即建模;网络2根据网络1的输出和工件螺距误差的仿真值而预报输出下一采样周期的综合补偿控制量.通过一系列试验研究,证明此控制策略能减少工件螺距误差80%以上,有效提高了试件丝杠的磨削精度.     

滚珠丝杠磨削加工热变形误差的分段补偿方法

在分析滚珠丝杠磨削过程中热变形误差变化的基础上,提出一种基于有限元法的确定螺距热误差分段补偿量的算法,并通过具体算例说明了该方法的计算过程,为保证滚珠丝杠的磨削加工精度提供了手段。     

滚珠丝杠螺距误差前馈补偿法提高X-Y工作台定位精度的研究

在详细论述了激光多普勒测量仪的原理及测量方法后 ,对滚珠丝杠螺距误差的情况进行了分析 ,通过软硬结合的方法对重复定位误差和螺距误差的补偿进行了研究 ,并且通过实验验证了方法的有效性     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...