机械定中心磨边机的使用与改进

我厂透镜磨边是使用南京仪表机械厂制造的Dm100型自动定中心磨边机,而透镜倒角则需要在其他机床上进行加工。我们将磨边机进行了局部改装,采用复合金刚石砂轮,使三道工序一次完成,提高了生产效率,保证了产品质量。加工产品零件如图1示:     

异形玻璃特征反求及在全自动玻璃磨边机中的应用

针对3M集成的异形玻璃磨边数控系统开发,研究异形玻璃的测量反求技术,重点开发基于小波基的玻璃轮廓B样条光顺算法和二维轮廓特征抽取的算法,并将上述算法应用于3M集成的数控磨边机系统中.     

异型玻璃磨边加工现状的分析与探讨

通过分析国内外异型玻璃磨边加工和磨边机的发展现状,提出使用机器人技术来解决异型玻璃磨边问题,探讨了异形玻璃磨边机器人的关键技术,并给出两种解决方案,对提高我国异型玻璃加工的自动化程度具有一定的指导意义。     

一种极坐标数控玻璃磨边系统

手工和模仿形玻璃磨边废品率高,难以实现规模化生产.本文提出一种极坐标数控玻璃磨边系统,并且针对磨边机旋转轴中心和磨轮中心的偏心和数控伺服系统的跟随误差等问题进行分析.最后通过玻璃相机显示屏的加工实例验证,本极坐标数控玻璃磨边系统具有误差小、精度高的特点,能够为规模化生产玻璃服务.     

高精度数控玻璃磨边机及其控制算法

针对传统的靠模玻璃磨边机存在的加工工艺复杂、自动化程度低的缺点,研制出数控玻璃磨边机,并提出相应控制算法。实践证明,该数控玻璃磨边机能有效改进加工工艺和提升自动化程度。     

汽车后视镜三维靠模磨边机的设计

比较各汽车后视镜磨边与倒角方法的优缺点,在仿形靠模原理基础上,研制了一种大曲率汽车后视镜三维靠模磨边机,该设备成型结构主要包括定轴转动部分和回转部分,一次装夹、一次磨削即可完成整个汽车后视镜的磨边与倒角,适用于工件的大批量生产。当汽车后视镜轮廓线变化时,只需更换靠模与定位靠模即可。用户使用证明,设备成型性能优良,减少了劳动强度,提高了汽车后视镜的磨边质量和生产效率。     

全自动异形玻璃磨边机3M集成数控系统的研究

介绍具有测量-建模-加工(3M)集成的全自动异形玻璃磨边机专业数控系统的开发,并深入研究了3M集成中随动测量控制算法以及系统集成.     

高硬度磨边接头的应用

介绍一种用于机械自动定心磨边机的经淬火处理的磨边接头。它能保证零件表面不会产生纹路，又有大大提高定点精度，而且还可长期保持磨边接头的形状精度，特别适用于大批量光学透镜生产。     

立式磨边机磨头机构的动态性能分析

机械设备的振型和固有频率与其振动现象的发生密切相关.为了减小振动、避免共振、提高磨边机的磨边质量,利用有限元分析软件ANSYS对立式玻璃磨边机的关键部件上磨头机构进行了动态特性分析.用实验的方法获取了结合面的动力学参数,并对结合面模型的建立过程做了详细地探讨.对刚性连接、弹簧阻尼连接的有限元模型进行了模态分析,并将分析...     

数控玻璃异形磨边CAD/CAM系统开发

为了解决玻璃异形磨边加工中质量及效率低下的问题,开发了数控玻璃异形磨边CAD/CAM系统.该系统可以针对玻璃加工中特殊工艺要求,完成从图形绘制到磨边及抛光代码的自动生成.通过使用遗传算法获得了玻璃加工最优路径;通过采用圆弧进退刀工艺,圆满地解决了玻璃磨边中结刀疤问题;通过抛光预补偿算法,大幅度提高了抛光效果.实践证明该CAD/CAM系统能够很好地满足玻璃异形磨边的要求,可以大幅度提高加工质量.     

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...     

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.     

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...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.     

Fractional order nonsingular terminal sliding mode control for flexible spacecraft attitude tracking

This paper investigates a fractional terminal sliding mode control for flexible spacecraft attitude tracking in the presence of inertia uncertainties and extern...     

奥氏体不锈钢表面双辉等离子渗锆的动力学

利用双辉等离子渗金属技术在0Cr18Ni9Ti奥氏体不锈钢表面制备了一层均匀、致密、呈良好冶金结合的渗锆合金层,并对1 060℃下的渗锆动力学进行了研究。结果表明:随着距锆合金层表面距离的增加,锆元素的含量呈梯度递减,扩散系数逐渐减小,而扩散激活能逐步增大;在1 060℃采用双辉等离子技术渗锆时,渗锆合金层表层的空位密度为2.945×(1012~1013)cm-2,与相同温度下采用常规渗金属工艺相比,提高了1~2个数量级。     

气化炉三维扫描测量与数据处理

以德士古气化炉耐火砖的内壁蚀损检测设备为基础,对采集到的点云数据做了进一步处理.通过对数据的筛选和剔除,实现了数据点的平滑降噪细化和精简.然后利用点云对整、网格划分和分色显示等方法,最终完成了内壁腐蚀情况的三维建模.重点讨论了点云数据的预处理及后处理的方法,并根据内壁耐火砖的腐蚀阈值,提出了一种气化炉内壁腐蚀区域的识别与分割方法.对耐火砖的腐蚀分析、气化炉的生产与维修提供了可靠依据,并在工程应用中获得了一致认可.