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激光线扫描测量原理及数据处理简介 总被引:9,自引:0,他引:9
概述了逆向工程的内涵,重点介绍了激光线扫描的测量原理和特点,分析了激光线扫描测量数据的处理流程,结合实际测量数据的表面重构结果,讨论了激光线扫描测量的应用。 相似文献
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为了提高管道在扩径过程中圆度和直径的测量精度及效率,设计了一套基于激光线扫描三维重构的管道直径及国度测量系统.系统利用激光线扫描传感器对管道外轮廓进行点云数据采集,结合上位机对图像数据进行滤波、去噪及分割,实现扩径管道外轮廓的三维重构,并利用最小二乘法计算重构的扩径管道直径和圆度.实验结果表明,该系统能够实现扩径管道直... 相似文献
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针对线结构激光扫描系统标定成本高,而双目立体视觉测量中立体匹配难的问题,提出了在双目立体视觉的原理上,结合线结构激光扫描的方法实现对被测物体的三维测量。该方法采用张正友相机标定方法对系统进行立体标定;采用BOUGUET’S法对左右相机图像进行立体校正;运用重心法进行激光中心线的精确提取。在图像校正的基础上,可快速实现激光中心线位置的立体匹配;再结合线扫描原理可完成对物体的扫描工作。最后,使用该系统对具有复杂自由曲面的鞋楦进行测量,结果表明:该方法能快速准确地测量出符合要求的三维数据。 相似文献
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准分子激光加工参数对表面形貌影响的模糊分析 总被引:1,自引:0,他引:1
采用准分子激光微细加工方法 ,选用不同的工艺参数加工Al2 O3 陶瓷材料试件。通过表面轮廓仪测量并计算表面形貌统计参数。分析了激光加工工艺参数对表面形貌的影响 ,利用模糊分析方法 ,就激光器的放大器电压、激光脉冲频率、激光扫描速度等工艺参数对表面形貌轮廓均方根值Rq 的影响进行了评价。结果表明 ,Rq 值随激光器的放大器电压和激光脉冲频率的增大而增大 ,随激光扫描速度的增大而减小。分析得出 ,激光加工工艺参数对表面形貌的影响程度不同 ,由大到小依次为激光扫描速度、激光脉冲频率、放大器电压。因此 ,可以通过合理地选择工艺参数获得所需求的表面形貌 ,为表面微观形貌修饰提供了参考依据。 相似文献
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Porous copper surfaces show their great merits in the applications of chemical reaction, sound absorption and heat transfer. In this study, a laser micromilling method is proposed to fabricate porous surfaces with homogeneous micro-holes and cavities of the size about 1–15 μm on pure copper plates in a one-step process. The laser micromilling was performed by a pulsed fiber laser via the multiple–pass reciprocating scanning strategy. Based on the measurement of scanning electron microscope (SEM) and 3D laser scanning confocal microscope, the formation of surface structures was investigated together with the laser ablation mechanisms. The effects of laser processing parameters, i.e., laser fluence, scanning speed, number of scanning cycles and scanning interval, on the formation and surface morphology of porous surfaces were systematically assessed. Furthermore, the wettability of the porous copper surfaces was also evaluated by measuring the static contact angle of water. The results showed that the laser fluence played the most significant role on the formation of porous copper surfaces. The average depth and surface roughness of porous copper surfaces increased with increasing the laser fluence and number of scanning cycles while decreased with the increase in scanning interval. The scanning speed played little influence on the formation of porous copper surfaces. These results can be closely related to the variation of energy density and re-melting process during the laser micromilling process. Moreover, all the copper porous surfaces were found to be hydrophobic. The contact angle of porous copper surfaces was significantly dependent on laser fluence, but weakly affected by the scanning speed and number of scanning cycles. 相似文献
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工艺参数对管材激光弯曲成形影响规律的研究 总被引:1,自引:0,他引:1
管材激光弯曲成形是一种柔性金属塑性成形方法。将连续的激光光斑简化为一间歇跳跃的方形匀强面热源,并考虑材料性能参数与温度的相关性,建立了管材激光弯曲成形的热-机耦合有限元工艺仿真模型,对成形过程进行了数值模拟。有限元模拟结果表明:在其他条件不变的情况下,激光弯曲角度随激光功率的增大而增大,两者基本上成线性关系;弯曲角度随扫描速度的升高而减小,随光斑直径的减小而增大,但当光斑直径减小到一定程度后,弯曲角度开始减小;弯曲角度随扫描包角的增大而增大,当扫描包角为180°时,弯曲角度达到最大,弯曲角度随扫描包角的继续增大而减小;扫描次数与弯曲角度间成近似的线性关系,且第一次扫描管材产生的弯曲角度最大。 相似文献
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Teeter MG Brophy P Naudie DD Holdsworth DW 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2012,226(3):263-267
A significant amount of research has been undertaken to evaluate the function of implanted joint replacement components. Many of these studies require the acquisition of an accurate three-dimensional geometric model of the various implant components, using methods such as micro-computed tomography or laser scanning. The purpose of this study was to compare micro-computed tomography and laser scanning for obtaining component geometries. Five never-implanted polyethylene tibial inserts of one type were scanned with both micro-computed tomography and laser scanning to determine the repeatability of each method and measured for any deviations between the geometries acquired from the different scans. Overall, good agreement was found between the micro-computed tomography and laser scans, to within 71 microm on average. Micro-computed tomography was found to have superior repeatability to laser scanning (mean of 1 microm for micro-computed tomography versus 19 microm for laser scans). Micro-computed tomography may be preferred for visualizing small surface features, whereas laser scanning may be preferred for acquiring the geometry of metal objects to avoid computed tomography artifacts. In conclusion, the choice of micro-computed tomography versus laser scanning for acquiring orthopaedic component geometries will likely involve considerations of user preference, the specific application the scan will be used for, and the availability of each system. 相似文献
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S. Hell S. Witting M. v. Schickfus R. W. Wijnaendts van Resandt S. Hunklinger E. Smolka M. Neiger 《Journal of microscopy》1991,163(2):179-187
We report on a confocal beam scanning microscope utilizing a continuous Xe short-arc lamp operating in the visible spectrum with unprecedented radiance. Measurements of lateral and vertical resolution will be presented and compared with those of an equivalent scanning laser microscope. Resolution of the white-light microscope is equivalent to that of the scanning laser microscope. White-light microscope images positively stand out from those of the scanning laser microscope by their lack of artefacts caused by interference. 相似文献
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Wook-Bae Kim Su-Dong Moon Hyoung-Soo Kim Jae-Hwan Yoo Hyoung-Chae Kim 《International Journal of Precision Engineering and Manufacturing》2009,10(5):141-146
This paper presents optics and fabrication process of key elements in a laser scanning unit for high quality laser beam printers
or multi-function printers with over 600dpi optical resolution which today’s commercial system shows. Considering the light
sources with different wavelength, optical characteristics in the laser scanning unit which includes a scanning lens and an
athermalization element are explained. Also fabrication technologies to realize high resolution laser system such as mold
design, core machining and injection molding processes are described. Finally, the hybrid lens as the athermalization element
having refractive and diffractive surface is suggested to compensate thermal defocus. The hybrid lens is fabricated and their
performance and effect on laser scanning unit are evaluated. 相似文献
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C. SCHAUDINN G. CARR† A. GORUR D. JARAMILLO‡ J.W. COSTERTON & P. WEBSTER§ 《Journal of microscopy》2009,235(2):124-127
Scanning electron microscopy is a useful imaging approach for the visualization of bacterial biofilms in their natural environments including their medical and dental habitats, because it allows for the exploration of large surfaces with excellent resolution of topographic features. Most biofilms in nature, however, are embedded in a thick layer of extracellular matrix that prevents a clear identification of individual bacteria by scanning electron microscopy. The use of confocal laser scanning microscopy on the other hand in combination with fluorescence in situ hybridization enables the visualization of matrix embedded bacteria in multi-layered biofilms. In our study, fluorescence in situ hybridization/confocal laser scanning microscopy and scanning electron microscopy were applied to visualize bacterial biofilm in endodontic root canals. The resulting fluorescence in situ hybridization /confocal laser scanning microscopy and scanning electron microscopy and pictures were subsequently combined into one single image to provide high-resolution information on the location of hidden bacteria. The combined use of scanning electron microscopy and fluorescence in situ hybridization / confocal laser scanning microscopy has the potential to overcome the limits of each single technique. 相似文献
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数字X线影像仪是计算机和激光技术快速发展的产物,而其中的激光扫描光学系统是其核心技术之一。针对数字X光影像仪的使用特点,对激光扫描系统中的Fθ镜头、光束扩展器、扫描器这几个关键部件进行了较详细的论述分析,提出并解决了其中一些关键问题,如光阑位置浮动对像质的影响、影响系统扫描光点大小的因素、扫描器的确定等。最后用ZEMAX光学设计软件对系统的光学性能进行了设计模拟,得到扫描光斑直径小于0.1mm、焦距和视场满足线性关系的设计结果。像质评价分析结果表明,所设计的镜头像质优良,轴上与轴外质量相当,像质达到衍射极限。 相似文献