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Microstructural Characterization and Performance Measurements
Published in Zhigang Rick Li, Organic Light-Emitting Materials and Devices, 2017
Scanning probe microscopy (SPM) is another relatively new class of microstructural characterization technique that probes materials on micrometer to subnanometer scale [38]. The SPM includes atomic force microscopy (AFM), scanning tunneling microscopy (STM), and tens of other related imaging techniques. Each SPM uses a sharp probe to scan the surface of the sample, point-by-point and line-by-line, to form an image of the surface. The simplest map is of three-dimensional topography. Other maps distinguish regions that are physically or chemically different from one another, revealing information about electrical, mechanical, magnetic, optical, and many other properties of the materials. Unlike electron microscopy, which requires vacuum and, often, some sample preparation, most of the SPM works in air and even in a liquid, with minimal or no sample preparation. The SPM measures surfaces in all the three dimensions: x, y, and z. Lateral topographic resolution for most SPM scanning techniques is typically 2–10 nm, and vertical resolution is typically better than 0.1 nm, far superior to the SEM. The SPM is the most powerful tool for surface metrology in our time. However, there are several limitations for SPM. For example, the sample must not have local variations in surface height of tens of micrometers. In 2012, Bruker announced the release of the photoconductive atomic force microscopy (pcAFM) module. The new accessory enables sample illumination while performing nanoscale electrical characterization [39].
Introduction
Published in Salah H. R. Ali, Automotive Engine Metrology, 2017
The second part introduces the necessary important industrial subject for advanced soft dimensional measuring techniques in micro- and nanometer scales (Chapter 2). Chapter 2 is dedicated to dimensional and surface metrology. The need for accurate dimensional measurements and quality engineered surfaces has become a necessary requirement to meet the challenges of modern technologies. Thus, advanced precise and accurate measurement techniques play a vital role in improving the function and quality of engineering products. The author discusses the advanced precise and accurate measurement techniques in terms of two basic approaches: the hard metrology techniques and the soft computing metrology techniques. The advanced soft metrology techniques include coordinate measuring machines such as roundness Talyrond machine, surface roughness devices, and optical microscopes. On the other hand, to complete the image, a new technical committee in ISO standards in the field of dimensional and geometrical product specifications and verification is established to address characterization issues posed by the areal surface texture and new measurement techniques. Here, different classification schemes of major advanced soft measurement techniques and their applications in industrial dimensional and surface metrology are reviewed. Moreover, current techniques, future trends under development and ISO strategies in this area are discussed.
Finger Contact Area Analysis with Convolutional Neural Networks
Published in Applied Artificial Intelligence, 2022
Thomas Ules, Matthias Haselmann, Michael Grieβer, Dieter P. Gruber
To produce the smooth counter surface a polyurethane based coating was cast on glass slides. For the rough counter surface the polyurethane coating was mixed with polyurethane based microspheres with sizes between 50 and 60 to provide the desired surface roughness (Ules et al. (2020)). To study the surface roughness, surface topography measurements were conducted with a 3D optical surface metrology system (Leica DCM8, Leica Microsystems, Germany). The images were obtained using an EPI 10x lens and the Focus Variation mode with green light. This allows for a theoretical optical resolution of 0.47 and a vertical resolution better than 30 . While the smooth surface yields a low average surface roughness Sa value of 0.16 the rough surface yields an average surface roughness Sa value of 5.7 . For a 3 dimensional image of the surface topography see Figure 1.
Finding optimal correspondence sets for large digital metrology point clouds using anisotropic diffusion analogy
Published in International Journal of Computer Integrated Manufacturing, 2021
Tsai and Hung (2005) presented a new method for surface metrology which uses structured light projection. They used a CCD camera to capture the projected patterns on the measuring surface. The methodology is effective in measuring local surfaces with a feasible tolerance or for the applications where the overall shape of an object needs to be modeled, such as reverse engineering. Although the evaluation time of this method is less than the situation in which a large number of data points are evaluated at once, uncertainties and limitations in the resolution of the predefined patterns should be considered. Dhanish and Mathew (2006) determined the effect of uncertainties in the measuring of circular features. The uncertainty in an inspection operation was investigated for the selected feature in the study. It has been proven that the number of sampled points plays the main role in the determination of uncertainties (Barari, 2011). However, instead of estimating the uncertainties which are costly and probabilistic, a feasible data reduction algorithm can be applied to decrease measuring and evaluation time (Lalehpour, Cody, and Barari 2017).
Experience-Based Product Inspection Planning for Industry 4.0
Published in Cybernetics and Systems, 2021
Muhammad Bilal Ahmed, Farhat Majeed, Cesar Sanin, Edward Szczerbicki
Dimensional metrology is also an important part of the post-manufacturing inspection of a manufactured workpiece. It is typically carried out in an environmentally-controlled metrology room and is done to ensure that the geometrical parameters of the workpiece meet design requirements for the purposes of quality inspection and control (Gao et al. 2019), however the role that metrology plays in quality control is not just restricted to workpieces. On-machine and in-process surface metrology is also used for the optimization of manufacturing processes and machine tool settings. This is based on the fact that the quality of the product’s surface texture reflects the characteristics of the manufacturing process. Surface form errors can be indicative of machine tool imperfections which can manifest as vibration, geometric error and thermal distortion (Whitehouse 2010).