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Optical metamaterials have revolutionized imaging capabilities by manipulating light‐matter interactions at the nanoscale beyond the diffraction limit. Bilayer nanowire grating configurations exhibit significant potential as exceptional elements for high‐performance polarimetric imaging systems. However, conventional computational approaches for predicting electromagnetic responses are time‐consuming and labor‐intensive, and thereby, the practical implementation remains challenging through an iterative design, analysis, and fabrication process. Here, a deep learning‐based design process is presented utilizing an artificial neural network (ANN) trained on finite element method (FEM) simulations that enables the prediction of bilayer nanowire gratings‐based electromagnetic responses. The study validates predictions through nanoimprinted bilayer nanowire gratings, demonstrating the reliability of the ANN's predictions. Furthermore, the research identifies critical geometric parameters significantly influencing transverse magnetic (TM) and transverse electric (TE) transmission. The ANN model effectively tailors design for specific mid‐wavelength infrared (MWIR) wavelengths, which may provide a practical tool for rapidly designing and optimizing metamaterial for high‐performance polarizers. [ABSTRACT FROM AUTHOR]

Reconfigurable assembly systems enable a family of products to be assembled in a single system by adjusting and reconfiguring fixtures according to each product. The sharing of fixtures among different products impacts their robustness to fixture variation due to trade offs in fixture design (to allow the accommodation of the family in the single system) and to frequent reconfigurations. This paper proposes a methodology to achieve robustness of the fixture layout design through an optimal distribution of the locators in a multistation assembly system for a product family. This objective is accomplished by (1) the use of a multistation assembly process model for the product family, and (2) minimizing the combined sensitivity of the products to fixture variation. The optimization considers the feasibility of the locator layout by taking into account the constraints imposed by the different products and the processes (assembly sequence, data scheme, and reconfigurable tools' workspace). A case study where three products are assembled in four stations is presented. The sensitivity of the optimal layout was benchmarked against the ones obtained using dedicated assembly lines for each product. This comparison demonstrates that the proposed approach does not significantly sacrifice robustness while allowing the assembly of all products in a single reconfigurable line. [DOI: 10.1115/1.3123320] Keywords: fixture layout, robust design, product family, multistation assembly

A general and efficient methodology has been developed to analyze dimensional variations of a welded assembly, taking into account of weld distortion. Weld distortion is generally probabilistic because of the random nature of welding parameters such as the welding speed, maximum welding temperature, ambient temperature, etc. The methodology is illustrated by a very simple example of two perpendicular plates fillet-welded to each other. Two steps comprise the methodology: establishment of a weld distortion database and tolerance analysis using the database. To establish the database, thermo-elastoplastic finite element analyses are conducted to compute the weld distortion for all combinations of discrete values of major welding parameters. In the second step of tolerance analysis, the weld distortion retrieved from the database is taken into account in addition to the dimensional tolerances of the parts. As a result of such an analysis, sensitivities of the assembly's dimensional variations to the part tolerances and weld distortion are obtained, which could provide a guideline for improving dimensional quality of the assembly. [DOI: 10.1115/1.3160319] Keywords: weld distortion, tolerance analysis, finite element analysis

In this paper "Ready-Made STL (RMS)" is defined as an STL model sophisticatedly planned and managed in advance in order to provide with all information needed for the build using an additive manufacturing process. Generating "RMS" from a raw STL model for build preparation typically undergoes three main processes for full optimization; diagnosis & repair of model geometry for geometric integrity and validity, modification of designed features for design compatibility, and specification of process parameters tight enough for process feasibility. In addition, as a subsidiary process for aid quality verification before the build, visualization of part build geometry simulated with surface roughness or build layers can also help full assurance of the build. This paper provides an executive review of previous approaches preparing "RMS" models and briefly addresses crucial issues resolved by corresponding approaches for build assurance in additive metal manufacturing as quick, efficient, and zero-fault printing process. [ABSTRACT FROM AUTHOR]

Directed energy deposition (DED), equipped with 5-axis tool mechanism and no additional machining process, turned out to be able to deposit overhang/undercut features with no support directly on a part in multiple directions. When performing the deposition, two additional axes of rotating and tilting newly added to the working table where the part is typically fixed need to be precisely controlled using an advanced process management technique. The previous approach for slicing algorithm corresponding with multi-axis tool paths along the part and providing a simple stepwise two dimensional layering process of repetitive ±90 degree tilting of the base table can cause unavoidable process delay whenever the base table needs to be tilted for conforming the geometry of overhang/undercut features. Another clear and present barrier to the approach, in addition, is the physical interferences between the tool and the workpiece moving separately during the build. This study proposes a Spherically curved layer (SCL) model providing interference-free 5-axis tool-part movement, a continuous and synchronized interaction between the tool and the part each separately but precisely controlled while kept contacted together, for the build of overhangs. A methodological approach generating SCL information directly from an STL model, followed by the implementation onto various overhang problems as case studies using the proposed methodology, will be discussed in this paper. [ABSTRACT FROM AUTHOR]

When considering the use of layered manufacturing (LM), there are many issues a designer has to address for handling a stereolithography tessellation language (STL) model, the de facto standard for LM. In this paper, we propose an Internet-based design visualization tool for decision support when optimizing the LM process in support of a highly interactive and collaborative virtual environment between CAD designers and LM processes over networks. It directly provides designers with an advanced preprocessor functionality, design visualization/optimization, as well as model display, repair, and slicing over the network. This can help smooth data transfer from CAD to the LM process with minimum inconsistency in CAD data. [ABSTRACT FROM PUBLISHER]

Rapid prototyping technologies can create a physical part directly from a digital model by accumulating layers of a given material. Providing tremendous flexibility in the part geometry that they can fabricate, these technologies present an opportunity for the creation of new product attributes that cannot be made with existing technologies. For this to be possible, however, various design environments including different fabrication processes need to be considered at the time of design. This paper proposes an extended design automation paradigm for design and fabrication of a new product attribute, surface macro-texture. [ABSTRACT FROM AUTHOR]