In recent years, the emergence of the Metaverse has created a significant impact worldwide. It represents the ultimate application of the latest information and communication technologies, introducing a brand new digital world to our society. With the industry sector being the core engine of our society, it holds the key to unlocking the potential of Metaverse application, particularly in the form of an Industrial Metaverse. The success of the Industrial Metaverse will greatly contribute to the overall development of the Metaverse. Therefore, this paper conducts a survey on the Metaverse to gather evidence of the growing trend towards an Industrial Metaverse. Furthermore, the key technologies required for implementing an Industrial Metaverse are analyzed. Lastly, the opportunities and challenges associated with the Industrial Metaverse are discussed.
Point set registration (PSR) is a key component of computer vision and pattern recognition tasks, with the goal of assigning correspondence and recovering the transformation that maps one point set to another, to achieve optimal alignment. The geometric quality inspection of aviation complex parts is mainly based on the digitization of the object, and realizes the effective evaluation of geometric quality by analyzing the digital information that characterizes the shape of object, which is of great significance for the high performance and reliability service of aircraft. However, PSR is the mathematical foundation for solving the point cloud alignment problems in the geometric quality inspection of aviation complex parts, the association between the two has not been systematically discussed, which leads to unfavorable research results. Therefore, this paper first gives a mathematical description of PSR. Secondly, the representative fundamental algorithms for PSR are introduced, mainly include: distance-based PSR algorithms, Kernel correlation-based PSR algorithm, mixture model-based PSR algorithms, global-local structure preservation-based PSR algorithms, feature-based PSR algorithms and learning-based PSR algorithms. Besides, the ideas, basic steps, and limitations of these are revealed. Thirdly, the works on point cloud alignment problems in geometric quality inspection of aviation complex parts and the PSR algorithms used are reviewed, i.e. the application of PSR. Finally, the development direction of PSR and the challenges faced in the geometric quality inspection of aviation complex parts are discussed.
One of the disadvantages of the permeability-based fluidic topology optimization method is that seepage inside the solid region makes the optimized results highly sensitive to the selection of the impermeable parameter in the standard Darcy model. In this paper, fluid seepage in the solid region is greatly reduced by imposing zero-velocity constraints along the normal direction of the fluid-solid interface. In each optimization iteration, the fluid-solid interface can be traced by setting a predefined threshold of design variables, and a body-fitted mesh is constructed explicitly by cutting the original square element into quadrilateral and triangular elements. Several representative fluidic optimization examples, for which problems associated with the seepage effect arise when using the standard Darcy model, illustrate the effectiveness of the proposed method.
As one of the hydraulic control systems of an aircraft, the hydraulic drive system of the aircraft cabin door can cause severe impact on the safe operation of the plane once failed. In order to enhance the safety and reliability of the hydraulic drive system of the aircraft cabin door, this paper takes the rotary hydraulic drive system of the aircraft cabin door as the research object, and analyzes its working principle. Additionally, five types of potential failures are summarized, including gain reduction fault in angular displacement sensors, blockage fault in flow control valves, air pollution fault, leakage fault in motor plungers, and motor plunger failure fault. Using the AEMSim software to establish a fault simulation model, the fault characteristics of the system under various fault conditions can be studied, which can effectively reduce the cost of physical simulation and testing, improve design efficiency and provide simulation data for other research.
The relationship between the crystallographic features and the anisotropic mechanical properties of a Laser Powder Bed Fusion (LPBF) fabricated GH5188 alloy were investigated. For this purpose, the LPBF-ed GH5188 alloy was subjected to a tensile test in two different tensile axis orientations, perpendicular and parallel to the building direction, which we call “horizonal” and “vertical” orientations correspondingly. The techniques of EBSD and TEM were employed to characterize the different strained samples. The results show that the LPBF-ed GH5188 alloy exhibits a<001>fiber texture with elongated grains along the building direction. Compared to the vertical samples, the horizonal samples acquire a higher Taylor factor and a higher KAM (kernel average misorientation) value during deformation, which lead to a better yield strength and a higher strain hardening rate. Furthermore, the texture of the deformed samples revealed that the horizonal samples have a better coordinated deformability, which leads to higher ductility compared to the vertical samples.