Image processing of the grinding wheel surface

Identifying the situation of grinding wheel wear and loading is a very important issue for high-efficiency grinding operations. This paper presents a new method that detects and identifies the chip loading and cutting edge wear of a grinding wheel using the image processing toolbox of the MATLAB package. The different optical characters of the metal chips and the abrasive grains are analysed. The Sobel operator is adopted to make the edge detections. A sensitivity threshold based on the global condition is used to lower the noise. Image dilation and erosion processes are used to ensure that the edge of each loaded chip is covered by a continuous section. The ratios of chips are calculated and displayed to monitor the wheel surface working status.     

Measuring wear of the grinding wheel using machine vision

This paper proposes a new method for measuring grinding wheel contours using machine vision. The vision-aided measuring system comprises a CCD coupled with a telecentric lens, back lighting board and frame grabber. Measuring the image of the specimen with a grinded gap substitute directly captures the image of the actual grinding wheel. Using this method makes the 3 D of the topography of the grinding wheel into the 2 D of the contour of the grinding wheel. This method significantly simplifies grinding wheel wear measuring procedures compared with the traditional methods. Therefore, the presented paper provides a new method to improve efficiency and cost on measuring wear of the grinding wheel. The results show that this developed system achieves a repeatable accuracy of ±3 μm for the measurement of the grinding wheel contours.This paper has not been published elsewhere nor has it been submitted for publication elsewhere.     

磨削加工对象多变时砂轮状态在线监测方法

在磨削加工对象频繁更换的情况下 ,工件的材料、加工要求、磨削条件和磨削参数经常变化 ,使声发射信号的信息也随之发生变化 ,为此提出基于声发射信号多变情况下的归原处理法 ,用于多变磨削加工环境下砂轮状态的在线监测。通过实验验证了该方法的可行性     

内冷却砂轮工装研制

由于磨削加工中过高的磨削温度,可采用内冷却砂轮磨削,将切削液直接浇注到磨削区内部,破坏了磨削区的封闭性,从根本上解决磨削温度高引起的工程实际问题.在普通磨床上采用内冷却砂轮磨削就必须提供内冷却砂轮工装,通过对砂轮内冷却总体方案、内冷却砂轮工装设计进行了研究,研制出了结构简单,性能可靠高的内冷却砂轮工装,将该工装用于M7130C平面磨床进行磨削加工,大大降低了磨削区温度,有效避免磨削烧伤,提高了磨削加工质量,效果良好.实验表明内冷却砂轮可加工某些难加工材料,扩大了磨床加工范围.     

磨床砂轮架设计与制造研究

就磨床的砂轮架在设计、制造、装配诸方面进行了比较详细、系统的研究与分析,揭示了磨床砂轮架中各零件之间的相互内在联系,指出了砂轮架设计、制造中如何对各种零件性能相互进行配合,从而满足不同性能的要求。     

成形砂轮磨齿工艺中磨削烧伤缺陷的研究与防止对策

根据成形砂轮磨齿工艺的特点,说明磨削烧伤产生的原因,经过分析研究与实践,给出烧伤缺陷的防止对策.     

利用成形砂轮在数控工具磨床上磨削复杂曲面

以数控工具磨床加工模具冲头为例,将砂轮修整成一定形状的成形砂轮,采用数控两轴直线插补的方法进行加工,通过大量的试验和生产实践证明,方法可行,精度易保证,生产效率高,有效解决了此类零件以前难以磨削的问题。     

异型石材加工中心磨抛砂轮创新改造设计研究

对石材数控机床磨抛砂轮现状进行了分析,研究了现有的加工方法和磨头结构,针对异型石材加工中心在工作过程中,对于复杂曲面磨抛时存在的问题,应用技术创新方法中ARIZ85算法流程寻求解决方案,进行了自动加工磨抛砂轮的创新改造设计。在对实际问题分析的基础上,完成了系统功能分析及原因分析,通过对创新原理应用,使用了技术矛盾分析,维数变换和分离方法的等算法,确定了异型石材加工中心磨抛砂轮设计方案,解决了在加工中心上无法实现复杂曲面磨抛的问题。     

The application of 3D-motif analysis to characterize diamond grinding wheel topography

The extraction of protruding diamond grains feature from the measured data of grinding wheels is the key to assessing their surface texture and predicting their functional performance. The 3D-motif analysis was utilized to identify the significant features. Based on 6-neighbourhood and wolf pruning, the tiny and insignificant motifs were eliminated and the surface of grinding wheel was segmented into large significant motifs. Four surface samples of #600 diamond grinding wheel were measured by using Alicona Infinite Focus Measuring Instrument and analyzed based on 3D-motif method. As the results shown, the 3D-motif analysis provided an effective method to segment the measured surface into significant features. The experiments also indicated that wolf pruning at 5% produced a proper count of the protruding grains extracted from grinding wheel surface.     

液膜阻尼砂轮主轴运动系统建模

根据达朗贝尔原理建立了带挤压液膜阻尼器的内圆磨床砂轮主轴动力学模型，并对其进行了无量纲处理及便于仿真研究和分析。     

图像边缘特征分析

图像测量技术是近年来在测量领域中形成的新的测量技术。在图像测量方法中,精确地确定图像的边缘位置极为重要。本文首先简要对图像测量系统进行阐述后,着重对图像边缘特征进行分析,并指出,边缘特征点处斜率最大,从而为实现亚象元边缘检测提供了理论依据。     

圆锥滚子外径表面磨削时导轮制导面的改进

采用无心磨削方式加工圆锥滚子时,导轮制导面形状呈锥形,会与滚子外圆产生干涉,深入探讨了产生此现象的原因,提出了解决方法,给出了计算公式。     

图像法在数字式水准尺自动检测中的应用

本文介绍了一种基于图像法的数字式水准尺自动检测系统的构成与测量原理,提出了一种动态的、能够实现对数字式水准尺的图像进行采集、处理的方法,在此基础上,给出了数字式水准尺图像边缘检测的关键电路和图像细分的算法,用于边缘检测的硬件电路准确、可靠;所使用的算法精炼、运算速度快、适应性强,二者相结合在数字式水准尺图像检测中取得了较好的效果,是数字式水准尺检测中一种实用的方法。     

基于模型的工业图像增强技术

井下原煤皮带监视图像由于照度低,粉尘所致的能见度差,采掘机振动引起固定在井巷壁支架上的摄像机抖动,井下供电电源波动以及经从井下至地面长距离传输等因素,所采集的图像受到的污染较为严重。针对这种情况,本文提出一种基于模型的工业图像增强技术,该技术将图像信号先经过非线性中值滤波器滤波,再基于原煤皮带机模型作边缘轮廓锐化处理,所恢复的图像质量较为理想,能够满足工程的要求。     

研磨中心上曲面自动磨抛的实验研究

硬质材料曲面工件的磨抛是超精加工中迫切需求的技术。目前自由曲面的磨抛仍采用手工完成,费时且效率低。磨抛需要高效率地去除曲面残留峰改善工件的粗糙度,同时还要保持曲面的形状精度。在类似加工中心(MC)的磨削中心(GC)上,采用参数表达的自动磨抛方式,对自由曲面进行了磨抛加工。结果表明,参数表达的自动磨抛可取用相同的刀具中心轨迹,仅仅去处残留峰的高度,而不改变曲面的形状精度,曲面工件的磨抛效果良好。     

金刚石砂轮表面形貌测量系统

为了实现对金刚石砂轮表面形貌的非接触精密测量,开发了基于干涉原理的金刚石砂轮表面形貌专用测量系统,研究了该系统的测量原理和关键技术。根据垂直扫描白光干涉显微测量原理以及被测对象的特征,提出了适用于砂轮测量的方法,研究了系统的自动扫描范围、垂直方向的扫描方法、单次测量三维表面的恢复算法和磨粒的识别算法。结合自行设计的夹具搭建了砂轮测量系统,并对多次测量拼接算法进行了实验分析。实验结果表明:基于区域重合大小(重合度为30%~50%)的拼接算法获得的拼接前后重合区域的相关系数均大于0.8,拼接后重合区域的高度差均小于0.4μm。得到的结果显示所搭建的系统可以恢复砂轮的形貌,其测量范围和精度满足砂轮磨粒评定和分析的要求。     

机床特性对陶瓷结合剂CBN砂轮磨削比的影响

通过用陶瓷结合剂CBN砂轮对45淬硬钢工件进行磨削试验,深入分析了机床特性对CBN砂轮磨削比的影响,获得了能够进行CBN砂轮高速高效磨削的机床特征参数。     

三维曲面数控磨削砂轮磨损测控与补偿研究

针对三维曲面数控磨削 ,设计测量仪 ,其和数控磨削系统相配合 ,完成砂轮磨损的测量和补偿 ,提高了三维曲面磨削精度及砂轮耐用度 ,并应用于电视机尾锥玻壳模具的磨削     

高速钢材料的粗金刚石砂轮轴向进给数控磨削机理研究

根据正交试验确定了影响高速钢材料的粗金刚石砂轮轴向进给数控磨削表面粗糙度值Ra的最主要因素是进给速度Vf.在此基础上,进行进给速度Vf单因素数控磨削实验,对数控磨削后表面粗糙度值进行了分析.     

Evaluation of wheel life by grinding ratio and static force

A degree of sharpness in wheel grains affects the surface roughness and dimensional accuracy in the grinding process. If a wheel with dull grains is used, the grinding force is increased and the surface roughness is deteriorated. In ovder to produce a precision component economically, the magnitude of the wear amount in the grinding wheel has to be limited. In this study, experimental evaluation of a wheel life varying with the grinding ratio and static grinding force was conducted. The grinding ratio and grinding force were measured to seek the grinding performance of the WA wheel. The relationship between the grinding ratio and static grinding force was presented.