• Journal of Aerospace System Engineering
• /
• v.13 no.1
• /
• pp.54-61
• /
• 2019

The 3D printing technology took the second place within the top ten rising technologies at the World Economic Forum in 2012. It arose as a core technology that would enable transformation in the manufacturing industry and develop new markets through the change of existing industry paradigms. Leading countries, like the United States of America, are actively expanding the use of 3D printing technologies within their defense areas. In order to utilize the technology within her defense areas, the Republic of Korea is planning to acquire defense spare parts manufacturing technologies and nurture professional defense personnel specializing in the 3D printing technology. Hence, this study offers various methods to efficiently apply reliable 3D printing spare parts to operation fields in the future by utilizing spare parts localization development management methods within existing weapon systems' development, manufacturing and sustainment phases.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.10
• /
• pp.94-105
• /
• 2020

Recently, most studies of 3D printing in construction have focused on the development of 3D printers and materials suitable for construction 3D printers. In comparison, there has been little research on design support tools that enable representative BIM data of building modeling tools to be applied to 3D printing. In addition, existing 3D printing slicing programs are commercialized around manufacturing, showing that they are unsuitable for construction 3D printing. Therefore, this research aims to develop a design support tool for 3D printing for buildings. The developed design support tool was validated based on arbitrary BIM data. Verification showed that wall pattern generation was modeled accurately without errors, and a calculation of the construction period showed that the formula presented in this study was valid. Furthermore, the maximum length of the mesh split was set to 100mm to minimize errors when converting to STL files.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.12
• /
• pp.182-189
• /
• 2019

3D printing technology is changing the paradigm of consumer-oriented design in supplier-oriented mass production. 3D printing technology in construction is expected to be able to replace existing wet methods along with modular construction. Recently, a number of cases of building construction using 3D printing using mortar-based materials have been announced in many regions, including North America, Europe, and Asia. In this study, we developed a design support tool with a slicing function to output 3D modeling for architecture for a 3D printing machine. We analyzed the process and the function of slicing programs that are commercially available. Seven slicing functions required for the architectural field were derived by analyzing cases, expert reviews, and related literature. The derived functions were extended from the slicing functions to develop the design support tools. Detailed algorithms and processes need to be developed for future derived functions.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.38 no.10
• /
• pp.817-829
• /
• 2014

One of the main issues in tissue engineering has been the development of a three-dimensional (3D) structure, which is a temporary template that provides the structural support and microenvironment necessary for cell growth and differentiation into the target tissue. In tissue engineering, various biomaterials and their processing techniques have been applied for the fabrication of 3D structures. In particular, 3D printing technology enables the fabrication of a complex inner/outer architecture using a computer-aided design and manufacturing (CAD/CAM) system, and it has been widely applied to the fabrication of 3D structures for tissue engineering. Novel cell/organ printing techniques based on 3D printing have also been developed for the fabrication of a biomimetic structure with various cells and biomaterials. This paper presents a comprehensive review of the functional scaffold and cell-printed structures based on 3D printing technology and the application of this technology to various kinds of tissues regeneration.

• Journal of the Korean Applied Science and Technology
• /
• v.35 no.3
• /
• pp.935-939
• /
• 2018

3D Printing technology is developing in various prototypes for medical treatment, food, fashion as well as machinery and equipment parts production. 3D printing technology is also able to fully be utilized to other industries in terms of developing its technology which has been reported in many field of areas. 3D printing technology is expected to be used in various applications related to $4^{th}$ industrial revolution such as finished products and parts even it is still carried out in the prototype model. In this study, we have investigated and developed conductive resin for 3d printing application based on reduced graphene oxide(rGO)/Polypyrrole(Ppy) composite and polycaprolactone(PCL) as a biodegradable polymer. The electrical properties and surface morphology of the conductive PCL resin based on therGO/Ppy composite were analyzed by 4point-probe and scanning electron microscope(SEM). The conductive PCL resin based on rGO/Ppy composite is expected to be applicable not only 3D printing, but also electronic materials in other industrial fields.

• Resources Recycling
• /
• v.27 no.1
• /
• pp.3-13
• /
• 2018

3D printing, also known as Additive Manufacturing (AM), is being positioned as a new business model of revolutionizing paradigms of existing industries. Launched in early 2000, 3D printing technology for architecture has also advanced rapidly in association with machinery and electronics technologies mostly in the United States and Europe. However, 3D printing systems for architecture require different mechanical characteristics from those of cement/concrete raw materials used in existing construction methods. Accordingly, in order to increase utilization of raw materials produced in the cement and resource recycling industry, it is necessary to develop materials processing and utilization technology, to secure new property evaluation and testing methods, and to secure database related to environmental stability for a long period which aims to reflect characteristics of an architectural 3D printing technology.

• Journal of the Korea Convergence Society
• /
• v.12 no.12
• /
• pp.267-272
• /
• 2021

This study would like to propose a certification of aviation components manufactured through 3D printing. Currently, many types of 3D printers are being used in various industries. Among them, a lot of research is being done in the aviation sector to manufacture drones and aviation components. However, the current level of 3D printer technology and the application of aviation components using it are lacking in many problems and related airworthiness certification standards. Furthermore, clear certification criteria for conformity and coherence are rarely presented. Therefore, we would like to propose matters related to certification of 3D printed equipment for application as aviation components. It is expected that 3D printing equipment will improve precision, reduce defect rate, sagging problem, and bed leveling problem will be solved in the future, and certification standards will be clearly established. In addition, we hope that the reliability of aviation components applied with 3D printing technology will be improved and the relevant certification standards will be further developed.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.9 no.1
• /
• pp.41-49
• /
• 2021

3D printing techniques have been recently adopted in the construction industry. It mainly utilizes additive manufacturing which is the fabrication process depositing successive layers of materials without any formworks. Conventional cementitious materials may not be directly applicable to 3D printing because 3D printable cementitious materials is required to satisfy such characteristics as pumpability, extrudability, and buildability in a fresh state. This study aimed to investigate rheological properties and required performances of 3D printable cementitious materials, by reviewing existing studies. Test methods and equipments, evaluation results and characteristics of mixture additives were compared. Based on reviews of existing studies, this study indicates that the viscosity is mainly relevant to the pumpability of 3D printable materials whereas the yield stress and thixotropy are important in securing buildability of the materials.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.2
• /
• pp.267-272
• /
• 2021

In this study, the output results of 3D printed exterior materials for application to buildings of various shapes are output tests using test specimens, in which 3D printing concrete is cast in a mold and accelerating agents are used to ensure stackability. The unit weight and strength characteristics of the body were analyzed. Compared to the unit weight of concrete placed in the mold, the unit weight of 3D printing concrete using accelerating agents tends to decrease by approximately 3.5% to 5.0%, and the compressive strength is the compressive strength of the concrete placed in the mold. In comparison, the compression strength of the output by 3D printing tended to decrease by approximately 36% to 46%. In the flexural strength, the compressive strength of the output through 3D printing decreased by approximately 36% to 46% compared to the compressive strength of concrete placed in the mold. The impact on the strength characteristics of 3D printed concrete using accelerating agents tended to decrease by approximately 2.0 to 5.8%. Therefore, 3D printing output accelerating agents can be used.

• Journal of the Korea Computer Graphics Society
• /
• v.21 no.3
• /
• pp.11-16
• /
• 2015

We present a system for generating 3D personalized figures. This system provides 3D figures model modification and combination functions based on the content-awareness. The integrity of the 3D model must be guaranteed at the time of slicing of the 3D model for 3D printing. In addition to this, with 3D printing, we generally have to print a hollow model in order to save money, time, and the integrity of the print. This paper proposes the automatic algorithm that creates the 3D individual figures with depth sensor and the easy UI functions for deformation, thickness adjustment, and combination of the generated 3D figures model based on the content-awareness. Our proposed method maintains the unique features of the generated 3D figures and ensures the successful 3D printing.