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Gear manufacturers need a dependable, comprehensive, and efficient inspection method to ensure manufacturing accuracy. Linear structured light provides a swift and effective solution to meet the rapid testing requirements of gear manufacturers. But its accuracy still needs to be improved. This method can obtain 33000 3D data points of a single gear tooth surface in less than 0.3 s. And based on this, evaluate the tooth profile error of the gear. The results indicate that the measurement deviation amounts to 1.47 μm in measuring gears of level 7 accuracy compared to the gear measurement center. The error mainly comes from the equipment error and the down-sampling process using the centroid method. In the measurement process, the larger the deviation between the contact position of the gear and the light and the focus position of the linear structured light, the greater the error. The larger the neighborhood search radius during the calculation process, the larger the error. [ABSTRACT FROM AUTHOR]

Sapphire single crystal has great potential applications in the semiconductor field. Due to its brittle characteristics. Crack failure on ultra-thin sapphire surface were prone to happen using tradition paraffin bonding clamping method during double-side processing, which severely restricted its processing efficiency. Thus, for overcoming the problem, the layer stacked clamping (LSC) method was proposed by using van der Waals forces and capillary forces that caused by dropping a liquid between workpiece and baseplate. A series of experiments were conducted for studying the characteristic of layer stacked clamping (LSC) method on polishing ultrathin sapphire wafer with double-side polishing machine. A self-made friction force test platform was built for learning the friction force between sapphire wafer and baseplate with different baseplate (stainless steel, cast iron, and aluminum alloy) and different baseplate surface roughness (Ra 3.6 nm, 68.2 nm, 210.1 nm, and 517.9 nm). Single-factor polishing experiments were carried out on baseplate with different flatness (PV value 5.3 μm, 9.8 μm, 19.9 μm, and 29.7 μm) and different thicknesses (0.082 mm, 0.104 mm, and 0.119 mm). The double-side polishing experiments were carried out to compare the polishing performance on the ultrathin sapphire polishing between LSC method and traditional paraffin bonding method. The results show that the friction forces of stainless steel and iron increase under the adsorption of droplets. Stainless steel performs higher friction force and is more suitable for making the baseplate. The inner fringe of limiter was cut off by the edge of the sapphire wafer, and a slope was thereby formed. According to polishing results, the LSC method has a higher efficiency on the clamping wafers than traditional paraffin bonding method. The surface roughness, flatness, and material removal rates are better than paraffin bonding. Finally, a smooth surface with a surface roughness (Sa) of 1.1 nm and flatness (PV) of 0.988 μm was obtained by the LSC method, significantly improving the clamping and processing efficiency of ultra-thin sapphire. [ABSTRACT FROM AUTHOR]

By using ABAQUS software, this paper simulates and analyzes the surface dynamic deformation characteristics of TC4 titanium alloy material by the thickness of the contacting foil under Laser shock texturing (LST). The dynamic deformation law of TC4 titanium alloy material was observed by Johnson-Cook failure mode. Compared with other surface modification techniques, LST effectively improves the long-standing speckle boundary effect and improve the surface roughness of titanium alloy materials. Contacting foil thickness is also a key process parameter in LST technology. In this paper, different thicknesses of contacting foils were selected for simulation. The simulation found that with the gradual increase of the thickness of the contacting foils, obvious micro plastic deformation occurred on the surface of the TC4 titanium alloy material, and the difference thickness of the contacting foils would directly affect the laser shock wave energy transmitted to the workpiece. Selecting the appropriate thickness of the contacting foil is beneficial to improve the effect of LST. [ABSTRACT FROM AUTHOR]

When automated pattern matching tools are used to execute user-knowledge pattern matching (UKPM) in the expert knowledge recommendation system (EKRS), user-knowledge matching is uncertain and the matching efficiency is low. To solve the above problems, the dynamic UKPM mathematical model is established and the "Entropy-Beta" method of crowdsourcing task assignment is designed to solve the model in the study. Firstly, the concept of Entropy is combined with crowdsourcing. The uncertainty of user-knowledge matching results is measured and the magnitude of the uncertainty is calculated. Secondly, based on the Beta distribution function, the accuracy of matching results is measured. The optimal matching results are selected and the matching results were sent to EKRS according to the matching probability. Thirdly, the knowledge recommendation process of UKPM is dynamically adjusted according to the matching probability. Finally, the comparison results of several algorithms showed that the Entropy-Beta algorithm could largely improve the accuracy, efficiency, dynamic regulation, and other performances of EKRS. [ABSTRACT FROM AUTHOR]

Grinding force is the most important characteristic parameter in the study of grinding machining mechanism, and it has an important influence on the quality of the machined surface and the service life of the grinding wheel. Accurate prediction of grinding force is significant to process improvement, machine tool design, and condition diagnosis. This paper uses the ABAQUS software to simulate the end grinding process of Si3N4 ceramics. In the abrasive removal model, in order to express the complex grinding conditions of the fine-grained grinding wheel better, this paper adopts the truncated polyhedral abrasive grain model, and the abrasive grains are randomly rotated multiple times to verify the model, which reduces the simulation grinding force error caused by the randomness of irregular abrasive grain model and improves the prediction accuracy. This paper establishes an abrasive grain distribution model, the unit number of abrasive grains is calculated from the equivalent volume of abrasive grains, and the grinding force of a single abrasive grain extends to the end surface; in the process simulation model, considering the influence of the change of radial linear velocity on the grinding force, the final grinding force is obtained by partitioning and summing. The experimental comparison shows that the grinding force model has high prediction accuracy in the end grinding with the fine-grained grinding wheel. [ABSTRACT FROM AUTHOR]