• 한국산학기술학회논문지
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• 제10권4호
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• pp.702-706
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• 2009

본 연구에서는 시작형 몰드재료로 우레탄 레진(TSR-755)을 이용하여 레이저 조형으로 다양한 형태의 냉각 채널을 가진 몰드로 가공했을 경우, 사출성형 상용패키지(Simpoe-Mold)를 사용하여 냉각채널 변화에 따라 사출물의 냉각시간과 변형량을 비교 검토 하였다. 해석결과, 사출물 주변의 적절한 냉각채널배치로 기존 금속재질의 시작형 몰드 대비 19% 최대 변형량 감소와 46%의 냉각시간 단축이 가능한 것으로 나타났다.

• 한국주거학회논문집
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• 제26권5호
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• pp.45-52
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• 2015

Following natural disasters, there is a need to develop temporary housing through the rapid installation of mass-produced prefabricated housing. This study has developed a model construction manual for prefabricated temporary housing installable in underground spaces. First, the temporary housing prototype was drawn based on opinion poll results from earlier studies. $4.32m^2$ was calculated as the basic unit of the temporary housing living space for one person. Units included panel type, box type and mixed-type, for a variety of field conditions and scales. In order to enable space expansion and movement desirable to the user, the prototype was combination of panel and box types. The drawn prototype was utilized as the basic design template for producing prototypes and for the manual. Second, the possibility of utilizing subway stations as temporary housing was verified through the production of the prototype, and the construction process was summarized in the manual. The manual was developed in the form of a checklist to provide a guideline for users to build with prefab materials.

• 한국정밀공학회지
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• 제25권3호
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• pp.157-164
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• 2008

While developing physical prototype from CAD model, rapid prototyping mainly focuses on two key points reducing time and material consumption. So, we have to change from a traditional solid model to building a hollowed prototype. In this paper, a new method is presented to hollow out solid objects with uniform wall thickness to increase RP efficiency. To achieve uniform wall thickness, it is necessary to generate internal contour by slicing the offset model of an STL model. Due to many difficulties in this method, this paper proposes a new algorithm that computes internal contours computing offset model which is generated from external contour using wall thickness. Proposed method can easily compute the internal contour by slicing the offset surface defined by the sum of circle swept volumes of external contours without actual offset and the circle wept volumes. Internal contour existences are confirmed by using the external point. Presented algorithm uses the 2D geometric algorithm allowing RP implementation more efficient. Various examples have been tested with implementation of the algorithm, and some examples are presented for illustration.

• 한국공작기계학회논문집
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• 제11권2호
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• pp.30-35
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• 2002

Nowadays, as the development period of new products becomes shorter and consumer's requirement is more various, the importance of Rapid Prototyping Technology has been rapidly increased. Rapid Prototyping makes prototypes or frictional parts directly using the 3D CAD data. But RP machines can make prototypes in limit size. For making large size prototype, we slice solid which is made of STL file, and then glue sliced solid. And if contact area of part is small, union solid will be easily destroyed for going down of adhesion. So we need to expand contact area, 1 suggest making a section into stair shape. This paper is concerned with slicing solid on STL file and improving on adhesion.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.945_946
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• 2009

This paper describes the development of the rapid battery charger for lead-acid battery. Due to heat which is caused by increased internal resistance during charging, it is difficult to increase charging current for the lead-acid battery. In this paper, the rapid charging algorithm which apply short discharging pulse current during charging procedure is developed and it makes the ion layer, which is generated during charging time, disappeared into electrolyte. The prototype battery charger based on resonant converter is developed for 48V battery charger and test procedure is introduced.

• 한국기계가공학회지
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• 제2권1호
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• pp.45-50
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• 2003

In any rapid prototyping process, the layer by layer building process introduces an area error between the staircase and the surface line specified by the computer-aided design model. This affects the dimensional accuracy as well as the surface finish for different Road Widths. This paper describes a methodology for computing the area error for any Road Width by the fused deposition modelling system. This technique can be applied to determine the best Road Width of the part, based on the minimum area error. This technique is verified by comparing the results with the experimental measurements of the area error with Road Widths.

• 한국생산제조학회지
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• 제9권1호
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• pp.30-37
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• 2000

In this paper rapid prototyping and precision casting technology have been developed for the manufacturing of inlet gear box of an airplane, Rapid prototyping is a new prototyping technology that produces complicated parts directly from three-dimensional CAD data with a high efficiency and has been extensively applied to various manufacturing processes. In the present work Selective Lase Sintering(SLS) system is utilized in order to manufacture prototype of the inlet gear box. Prototyping technology using SLS is also investigated from the viewpoint of accuracy. Using the SLS master the casting products are manufactured through several processes such as : vacuum casting lost wax shell casting and investment cast-ing. The shrinkage characteristics of wax and cast iron in the casting procedures are considered and then reflected to the design procedure so that the accuracy of the product is improved consequently.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.605-609
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• 1996

In order to ensure that the prototype corresponds as closely as possible to the serial part subsequently to be manufactured, the materials used for the prototye should, wherever possible, be identical to those used in production. In case of metallic parts, however, this demand is still not completely fulfilled by the available Rapid Prototyping techniques. Since only conventional manufacturing processes caan currentlybe used to produce metallic prototypes directly, these are extremely cost and labor intensive. For this reason, work is being undertaken worldwide to develop Selective Laser Sintering (referred to SLS) and Laser Generating for direct manufacture of metallic parts. In this paper the results of both process developments are reported. As the present results show, they have great application potentials in prototyping tools, especially molds and dies.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.433-438
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• 2004

The rapid machining of prototypes plays an important role in product process. Rapid Prototyping(RP) is the widespread technology to produce prototype. But, it have many problems such as shrinkage, deformation and formation occurred by hardening of resin and stair shaping, On the contrary, high speed machining(HSM) technology has many advantages such as good quality, low cost and rapid machining time. Moreover, it is possible to use the material of original product. This paper presents manufacture of trial product by HSM and optimization of machining condition for high productivity in the view of manufacturing time and average error. For example, propeller is machined by the surface machining of thin surface parts. Experiments are designed of machining conditions by Latin Square method and machining condition is optimized and selected by ANOVA

• 한국정밀공학회지
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• 제22권10호
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• pp.99-106
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• 2005

This paper presents manufacture of mock-up by HSM and optimization of machining condition for high productivity in the view of manufacturing time and accuracy. The rapid machining of prototypes plays an important role in building mock-up. Rapid Prototyping(RP) is a technology to make prototype. But, it have many problems such as shrinkage. deformation and formation occurred by hardening of resin and stair shaping. On the contrary, high speed machining(HSM) technology has many advantages such as good quality, low cost and rapid machining time. HSM and RP is compared for machining efficiency. Experiments are designed by Latin Square Method and machining condition is optimized and selected by ANOVA. For example, propeller is machined by the surface machining of thin surface parts.