Optical techniques for on-line measurement of surface topography

Optical techniques have great potential for non-destructive and on-line measurements of surface roughness during manufacturing. This paper reviews the state-of-the-art in a number of optical techniques including specular reflectance, total integrated scatter, diffuseness, angular scattering distributions, speckle, ellipsometry, and interferometry. The distinction is drawn between the more quantitative but slower profiling techniques and less quantitative, parametric techniques, which are faster and hence more useful for high-speed monitoring of surfaces. Overall, no currently available technique combines accuracy and speed and is therefore suitable as an on-line metrological tool for roughness measurement of engineering surfaces. Speckle techniques hold perhaps the greatest potential as accurate, high-speed metrological tools     

Emerging chemical sensor technologies for use in on-line applications

Advances in instrumentation and process control capabilities are being driven by the increased sensitivity of analytical chemistry methods, the commoditization and ruggedization of instruments and associated electronics, and changing consumer concerns and expectations, as well as government regulations. The emergence of biotechnology methods for the detection of contaminants, and the miniaturization and ruggedization of more standard analytical instruments based on mass spectrometry and infrared spectroscopy will be discussed as related to on-line process monitoring.     

表面组装在线检测中模板匹配的研究

作为重要的在线检测技术,自动光学检测是保障表面组装质量的主要手段。深入分析自动光学检测中的关键技术——模板匹配,应用实数编码的改进遗传算法进行模板匹配寻优。试验表明该方法的匹配速度和匹配精度均较为理想,该方法是可行的。     

Attitude-sensor-aided in-process registration of multi-view surface measurement

A novel method for in-process registration of 3D point clouds scanned from different views is presented. A miniature attitude sensor, which can output its pitch, roll and yaw angles in real-time, is mounted on the scanner. The relative pose between the attitude sensor and the scanner is calibrated in advance by a simple yet effective algorithm. When the scanner is moved from one standpoint to another in a measuring process, the real-time readings of the attitude sensor is utilized to compute the rotation movement of the scanner. After applying the rotation transformation to the current point dataset, the translation movement is efficiently determined by exploiting the normal vector constraint between the correspondence points. The rigid transformation obtained fully automatically can serve as a qualified initial estimate for further fine registration. Experiments demonstrate the applicability of the proposed method.     

光学薄膜表面微细缺陷在线检测方法研究

为了对光学薄膜进行精密光学检测,需要采用数个具有高解析度的线阵CCD相机进行光学薄膜缺陷图像的同步采集。基于计算机视觉的理论,提出了一种有效的自动质量监测方案,实现对光学薄膜表面微细缺陷项目的检测,并根据检测结果驱动打标机对光学薄膜缺陷进行自动标识和定位,该方法具有高精度、实时、在线和非接触的显著优势。探索性实验结果表明,采用该方法可获得光学薄膜表面缺陷的清晰图像,缺陷的细节能够得到很好的展现,并且能够完成缺陷特征的提取与识别。     

A mobile complex for on-line studying water areas and surface atmosphere

The complex is intended to perform continuous measurements of concentrations of chlorophyll a and dissolved organic substances by the laser induced fluorescence method, evaluate a state of the photosynthetic system of phytoplankton cells, and record readings of the CO₂ gas analyzer, sensors of sea water saltiness, pH, and temperature, and solar illumination meter. The mobility of the complex ensures a possibility of its operation on different ships and under stationary conditions. The configuration of the complex can be promptly changed for solving the current problem by promptly adding or replacing separate devices and sensors of the complex, as well as the software integrating all devices and data into the system. It is possible to use standard, vibration-resistant laboratory equipment, since the housing of the designed device ensures protection against the marine environment. Results of in-situ measurements performed in the Peter the Great Gulf (Sea of Japan) in 2012 are given.     

大型薄板曲面件在机测量技术的研究

为解决大型钣金曲面件因体积大、易变形、装卸不便等给测量带来的困难,提出了一种曲面测量的新方法即在机原位测量方法,并将其成功应用于某大型曲面件喷丸成形机上,实现了大型喷丸成形曲面件的在机测量.该测量方法使测量与加工采用同一基准,消除了因基准不重合带来的测量误差,提高了测量精度:避免了工件的重复装夹,提高了测量效率.采用曲线曲面匹配和误差分离技术对测量数据进行处理,完成了对被测件的评价.大型喷丸成形曲面件在机原位测量系统的研制成功验证了所提出的测量方法是可行的.     

蓄电池在线智能监测仪的设计

蓄电池作为电力系统的后备电源,其维护工作对保证电力系统的安全运行具有重要意义。对蓄电池实施在线监测并及时发现失效电池,是蓄电池维护工作的重中之重。文中介绍一种以单片机ADuC831为核心的新型蓄电池在线智能监测仪,能实现对蓄电池无论在浮充状态还是充、放电动态过程中的状态检测。着重介绍其软硬件设计方法。     

螺纹的重复切削

在使用配有ＮＵＭ数控系统的机床进行螺纹切削时 ,可以随时中断螺纹切削 ,并且从卡盘上取下工件进行其它的处理 ,例如测量、淬火等。然后重新将工件安装在卡盘上继续进行螺纹加工 (并且可使用与粗加工循环不同的主轴速度 )。当工件重新安装后 ,其轴向位置及角度位置可能与以前的位置不同 ,因此必须使用“螺纹重复切削循环”(恢复螺纹切削 )来示教螺纹的新位置。通过调用Ｘｐｏｓｔｅａｃｈｉｎ(主轴角度定位用Ｓｐｏｓｔｅａｃｈｉｎ ,主轴 1对应Ｅ90 10 0 )手动地执行螺纹位置的示教功能来确定粗加工螺纹的刀具位置及轴向位置 (或在Ｘ轴方…     

Application of the contact potential difference technique for on-line rubbing surface monitoring (review)

The Kelvin technique for measuring contact potential differences has been adapted for continuous non-destructive monitoring of changes in the electron work function of a rubbing surface. The method can be used to investigate tribological materials for a wide range of conditions, including changes in load, sliding speed, and environment, with or without lubrication. It relies on the sensitivity of the work function to the various events which accompany friction, e.g., plastic deformation, creation of new surface material, adsorption, oxidation, phase changes and redistribution of alloy components. At present, this is the only method which is sensitive to both surface and near-surface defects and permits study of one of the two interacting surfaces during sliding. Current work emphasizes two aspects of sliding behavior: (1) critical points with respect to changes in normal load, with relevance to materials selection and optimization, and (2) the kinetics of friction processes, including periodic changes which may be related to those in fatigue. This revised version was published online in June 2006 with corrections to the Cover Date.     

Caveat on the use of alloys for surface replication

Some replicas of plant cell surfaces produced by platinum/palladium evaporation were of very poor quality. Scanning electron microscope X-ray microanalysis showed that only Pd was evaporated from the Pt/Pd alloy, leaving the Pt on, or alloyed with, the tungsten filament used for evaporation.     

On the use of a modular system for microtopographical surface measurement

Conventional apparatuses for roughness measurement have one important shortcoming. Being built around a microprocessor they do not allow any access to the software and permit only a choice among the classical parameters selected by the manufacturer. The user cannot add any new program allowing a continuous extension of the capacity. The system presented here permits both this continuous extension and the use of a large range of microcomputers and devices.     

阳极溶出伏安法在地表水重金属在线监测中的应用

我国的地表水安全形势已经非常严峻,尤其是重金属污染事件的频发。引起了有关部门对饮用水源安全的高度重视,环保部门也加强了对饮用水源的监测力度。在对地表水重金属的分析过程中,地表水标准中对重金属的监测方法不能满足各种重金属项目监测方法的要求,实验以Jaroslav Heyrovsky在1959年发明的阳极溶出伏安法在对地表水进行重金属项目的实时监测进行探讨。     

A model-based methodology for on-line quality control

An on-line model development and quality control methodology is presented for manufacturers in the process industries with the goal of enabling automated quality assurance. Given appropriate process instrumentation, the methodology starts with the characterization of statistical variation for the process while operating in steady state. Significant process conditions are then perturbed by six standard deviations to bound the expected long-term process variation including lot-to-lot variability of feedstock materials. If the process is found to be robust, acquired process data is used to model the process behavior using principle components analysis (PCA). The PCA model is then used to accept and reject manufactured parts given real-time process data. This methodology is applied to an instrumented injection molding process that is subjected to 12 common process faults. The results indicate that the methodology was able to detect every one of 33 defective molding cycles caused by eight of the imposed faults as well as two additional faults that did not result in observable defective products. The quality controller did not detect the two remaining imposed process faults that did not produce defects and also rejected three molding cycles (2% of the total) that appeared to produce acceptable products.     

Fast measuring with microcomputers for on-line weighing

Output signals from weighing systems suffer from the finite time lag of the scale and other error signals caused by vertical movements of the load. Efficient digital filters were designed and tested to eliminate these error signals with respect to low computing and programming expenditure. The main tests were made with the weighing of freight trains in motion up to velocities of 120 km/h.     

支持在线重组的产品信息统一表达

研究了实现产品信息统一表达的思想及方法，针对产品信息的两种标准即STEP产品数据标准和SGML产品文档信息标准，研究了EXPRESS语言与XML语言模式匹配关系以实现两者的一致表达，研究了XML表达的STEP和SGML的网上动态关联，给出了统一表达的实例以证明可行性。     

Repeated clamping locking device for magnetic bearing flywheel

针对磁悬浮飞轮锁紧装置用整体碳纤维弹片不便拆卸和一次性锁紧装置不可重复锁紧/解锁的缺点,提出了一种基于分立式弹片释放机构的可重复抱式锁紧装置.介绍了锁紧装置的结构、工作原理和弹片方案,通过将弹片释放机构等效为悬臂梁质量块模型,对其进行了静力学和动力学分析.基于分析结果,选择灵敏度较高的结构参数作为优化设计变量,并考虑结构强度、解锁力和一阶共振频率,以软件iSIGHT为平台,对弹片进行多学科优化设计.优化结果表明,弹片个数为10时,弹片总质量达到最小为207 g,比初始质量477 g减少了56.6％.根据优化结果加工了一套锁紧装置,并利用正弦扫频振动和随机振动试验对其进行验证,验证结果显示该锁紧装置能够有效保护飞轮系统.     

形态滤波在中厚板表面裂纹在线检测中的应用

用面阵CCD摄像机采集中厚板表面图像，对采集到的图像进行形态滤波的Top-Hat变换，并结合阈值处理及连通区域搜索等算法，可以在线检测中厚板的各种表面裂纹缺陷，包括横向裂纹、纵向裂纹、星状裂纹等。根据从生产线上采集到的图像分析了中厚板裂纹缺陷的典型特征，并对形态滤波中的结构元素选取进行了研究。该算法已用在中厚板生产线的表面缺陷在线检测系统中。     

在线传感器性能评估技术研究

为了实现在线监视传感器性能,从实用的角度探讨了在线传感器性能评估技术.确定以传感器输出数据的有效度作为评估指标,提出利用小波变换对传感器的输出时间序列进行消噪预处理,运用人工神经网络预测传感器输出值,并与实测值进行比较求出残差,由此来确定传感器的有效度指数.实验结果表明,这是一种有效的在线传感器性能评估方法,并能客观地反映过程参数的突变情况.