Computer technology influences the capability to enhance the functionality of manufacturing and product design technologies. Innovations in computational design and digital manufacturing empower designers and manufacturers to create novel representations and algorithms for designing, analyzing, and planning the production of highly complicated products achievable through state-of-the-art technology. Various principles, including computational physics, geometric reasoning, and automated spatial planning, enable engineers to generate entirely new categories of products in the footwear industry. This study aims to review the methods and tools that have been published in the literature for the last twenty years, and provide a better understanding of the parameters, tools, and controls that contribute to the design and manufacturing processes of shoes. The main focus is on highlighting the product design-related trends within the footwear industry. A structured framework becomes apparent in the literature through the grouping and presentation of information. This framework facilitates drawing conclusions about the trends and existing needs derived from in-depth research in the field of footwear. Additionally, it reveals the upcoming methods and tools that will contribute to the enhancement and development of this emerging and promising industry sector. In conclusion, the categorization limitation within the footwear industry could serve as the foundation for exploring key areas to be analyzed further in other industries, for instance, in furniture, clothing, and packaging.
In this research, an investigation related to the tensile testing of 3D-printed specimens, under different fabrication parameters, is presented. The control samples were fabricated using Recycled-PETG: EVO (NEEMA3D™, Athens, Greece). It consists of recycled polyethylene terephthalate glycol (PETG) raw material, already used in industry, modified so that it becomes filament and can be printed again. More specifically, the parameters set to be studied are the percentage of infill, the speed and the type of infill. Both infill density and printing speed have three value levels, whereas for the infill pattern, two types were selected. Two sets of 18 specimens each were fabricated, with respect to the different parameter combinations. Through the results of the tests, the maximum tension of each specimen was obtained separately. Of the three parameters defined, it was found that the most important are the type of infill (44.77%) and the percentage of infill (24.67%). Speed (13.22%) did not strongly affect the strength of the specimens. In conclusion, the empirical model developed was considered reliable in terms of the value of the squared error, R-sq(pred) (97.72%), but also of the rest of the resulting analysis residual graphs (through the full factorial design).
1 December 2022 in Journal of Graphic Engineering and Design
Materials are a mainstay of both industry and everyday life. The manufacturing and processing of materials is a very important sector as it affects both the mechanical properties and the usage of the final products. In recent years, the increased use of 3D printing and, by extension, its materials have caused the creation of gaps in terms of strength that require further scientific study. In this study, the influence of various printing parameters on 3D-printed specimens made of polyethylene terephthalate glycol (PETG) polymer was tested. More specifically, three printing parameters were selected—infill, speed, and type—with three different values each (50%, 70%, and 90%), (5 mm/s, 20 mm/s, and 35 mm/s) and (Grid, Rectilinear, and Wiggle). From the combinations of the three parameters and the three values, 27 different specimens were obtained and thus, 27 equivalent experiments were designed. The measurements were evaluated, and the process was modeled with the Artificial Neural Network (ANN) method, revealing a strong and robust prediction model for the tensile test, with the relative error being below 10%. Both infill density and infill pattern were identified as the most influential parameters, with the Wiggle type being the strongest pattern of all. Additionally, it was found that the infill density acts increasingly on the strength, whereas the printing speed acts decreasingly.
Nowadays, the circular economy model is basically built on the efficient use of resources and the maximization of the product’s lifetime as long as possible, by recovering, reusing and recycling existing materials and products. Comparing circular economy with the new trend of customized products, there is an opportunity for the production of personalized products with less associated environmental costs. As a key factor can be considered the 3D printing technology, which is already widely accessible, offering customisable possibilities without expensive tooling based on individual specifications. Furthermore, the opportunity for recycling and degradation of different plastic materials and the creation of a filament for 3D printers has large impact on the product life cycle. The aim of this study is to highlight the management of recyclable plastic by creating new customized products. Souvenir industry has been chosen as a representative example which covers a big number of different products offering simultaneously a mass customized character.
Modelling with 3D CAD (Computer Aided Design) tools has reached a point that its complexity is difficult to be controlled without the use of programming tools. Both general purpose CAD systems and specialized CAD pieces of software allow their programming with textual or visual interface. The designer is offered with a variety of tools in order to automate the design process and handle its geometrical complexity. The present paper deals with the use of CAD based visual programming for product designers, who want to use unusual geometries based on 2D patterns and present their work to the final user using high-end rendering images. The proposed designs can be customized to a great extend and contribute towards their increased added value. At the same time, a family of products can be presented, when the design parameters used get alternative values.