• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권8호
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• pp.487-494
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• 2000

This paper describes the design, fabrication and experiments of surface-micromachined aluminum micromirror array with hidden pin-joints. Instead of the conventional elastic spring components as connection between mirror plate and supporting structure, we used pin-joint composed of pin and staples to support the mirror plate. The placement of pin-joint under the mirror plate makes large active surface area possible. These flexureless micromirrors are driven by electrostatic force. As the mirror plate has discrete deflection angles, the device can be ap;lied to adaptive optics and digitally-operating optical applications. Four-level metal structural layers and semi-cured photoresist sacrificial layers were used in the fabrication process and sacrificial layers were removed by oxygen plasma ashing. Static characteristics of fabricated samples were measured and compared with modeling results.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 춘계학술발표대회 논문집
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• pp.159-162
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• 2001

A combined finite element and experimental study based on the characteristic length method is performed to investigate the strength and behavior of the pin joint in composite control rod. The failure is estimated by the Yamada-Sun and Tsai-Wu criteria on the characteristic curve. The gap elements are used to simulate the contact between the pin and the composite fitting with hole. The accuracy and applicability of the method are validated by the joint tests. All the specimens were failed in the bearing mode in the test and finite element analysis, and good agreement was found between the predicted and test results on the joint strength of composite control rod.

• Composites Research
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• 제25권6호
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• pp.186-190
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• 2012

복합재료가 기계부품 및 항공기 구조물에 폭 넓게 적용됨에 따라, 복합재료 구조물에서 가장 취약한 복합재료 체결부의 설계는 매우 중요한 연구 분야로 대두되고 있다. 본 논문에서는 다양한 원공공차를 가지는 복합재료 볼트 조인트와 핀 조인트의 강도를 상호 비교하였다. 실험결과로부터 조인트의 원공공차가 $880{\mu}m$일 때 원공공차가 $0{\mu}m$ 보다 첫 번째 파손하중의 볼트 조인트는 24.2 %, 핀 조인트는 51.3 %의 강도저하가 발생되었다. 또한, 이에 대한 유한 요소 해석을 수행하여 파손지수를 계산하고 실험값과 상호 비교하였다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2002년도 춘계학술대회논문집
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• pp.153-160
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• 2002

This paper shows the possibility of performing Lap joint using the friction stir welding and the determination of tool's dimensions for FSW in Milling machine. This research also is reported on obtaining the tensile-shear strength, 9.319 ( kgf/mm$^{2}$) and the energy absorption, 2,682 (kgf-mm) under this experiment. The optimal tool's dimensions and method for Lap joint in 2tmm aluminum alloy plate using FSW is as follows; The diameter of shoulder and pin are 9 $\phi$mm and 3$\phi$mm, the length of pin is 3.6mm. The conditions of shoulder of tool is not pressed into original base metal.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 춘계학술발표대회 논문집
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• pp.74-78
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• 2003

Stress analysis was conducted with finite element method to study the stress distributions in both single-pin and multi-pin loaded composite laminates. The various parameters involved in the design of the joint method were considered. The stress distributions in the vicinity of the holes were predicted considering the effects of various parameters such as the lay-ups, number of pins, number of rows, row spacing, and hole patterns. The results show that the performance of joint is greatly affected by these parameters.

• 임산에너지
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• 제18권2호
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• pp.84-91
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• 1999

The objective of this study was to present creep and the effects of mechano-sorptive deflection of drift pin moment resisting joint between LVL members under changing relative humidity (RH) conditions. The LVL members with steel gusset were jointed by a square pattern of eight injected drift pin. Three diameter drift pins were used to test specimens (6mm, 10mm, and 16mm). The creep test was conducted under two constant loading conditions : one at 30 kgf(840 kgf-cm) and the other at 60 kgf(1680 kgf-cm). The experiment was conducted in an open shed outside. (1)The total rotation creep model of moment resisting joing can be expressed as the sum of the creep of controlled environment (3-parameter model), dimensional change and mechano-sorptive deflection resulting from the variable environment. (2)Mechanosorptive rotation creep is recoverable as moisture content increases during adsorption. Least squares method for linear regression analysis was performed using mechano-sorptive rotation creep as the dependent variable and moisture content as the independent variable. The slope of low moment specimens are compared with those of high moment. This means that low moment condition is more easily affected by changes in humidity than high moment conditions. (3)Although creep deflection is higher for small diameter drift pin than for large diameter drift pin, the shape of creep deflection curves for all specimens is similar.

• Journal of Advanced Marine Engineering and Technology
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• 제27권6호
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• pp.728-735
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• 2003

This paper shows the possibility of performing Lap joint using the friction stir welding with $2mm^t$ aluminum alloy plate and the determination of tool-dimensions for FSW in milling machine. This research also is reported on obtaining the tensile-shear strength, 91.3 (MPa) and the energy absorption, 26.3 (J) for Lap jointed specimen. The optimal tool-dimensions and method for Lap joint using FSW is as follows; each diameter of shoulder and pin is $9\phi(mm) and 3\phi(mm)$, the length of pin is 3.6(mm), Pressing the shoulder of tool into original base metal is not reasonable.

• 대한의용생체공학회:의공학회지
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• 제15권3호
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• pp.289-294
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• 1994

A new type of electrogoniometer to measure the three dimensional motion of the human knee joint was developed. This instrument is composed of six potentiometers: four arranged for two universal joints, one for pin joint, and one for axial rotation measurement. The voltage change in six potentiometers were collected through A/D converter for acquisition, storage and analysis. With a developed instrument, gait analysis was performed. Compared to earlier developed triaxial type goniometer, new instrument shows its convenience in application and accuracy in measurement.

• Composites Research
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• 제25권3호
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• pp.65-69
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• 2012

본 논문에서는 금속 핀으로 보강된 일체성형 복합재 단일겹침 체결부에 대해, 보강 핀이 체결부의 파손거동에 미치는 영향을 시험으로 연구하였다. 핀의 지름(0.3, 0.5, 0.7 mm)과 밀도(0.5, 2.0, 4.0%)를 달리하여 총 6종류의 시편을 제작하였다. 복합재료와 보강핀은 각각 Toray사의 일방향 탄소-에폭시 프리프레그 T700-12K-31E#2510와 스테인리스 강이다. 핀 밀도가 매우 낮은 한 경우(0.5%)를 제외하고는, 모든 체결부에서 두께방향 핀의 보강으로 인해 초기균열의 발생이 더 빨라지는 것으로 나타났다. 그러나 극한강도는 최대 45%까지 증가하고, 특히 접착면의 완전한 분리 후에도 대변형 상태에서 핀이 추가적인 하중을 지지함으로써, 구조물이 안정적 파괴거동을 갖도록 하는 것을 확인하였다.

• Composites Research
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• 제31권6호
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• pp.323-331
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• 2018

스테인리스 강으로 제작된 요철핀의 보강이 복합재 모자형 체결부의 풀오프 강도에 미치는 영향을 시험으로 연구하였다. 요철핀에는 물리적, 화학적 표면처리를 수행하였고, 체결부의 외피와 보강재가 만나는 영역에 두께방향으로 핀을 삽입하였다. 모자형 체결부 시편은 요철핀을 포함하여 일체성형으로 제작하였다. 사용된 요철핀의 지름은 0.3, 0.5, 0.7 mm로 세 가지이다. 핀의 삽입밀도는 외피와 보강재가 만나는 면적 기준으로 0.5, 2.0% 두 가지이다. 요철핀과 일반핀의 효과를 비교하기 위하여 0.3 mm 일반핀을 2.0% 밀도로 삽입한 시편을 추가로 제작하여 시험을 수행하였다. 0.3, 0.5, 0.7 mm의 요철핀을 0.5%의 밀도로 삽입한 시편의 강도는 보강되지 않은 시편 대비 각각 45, 19, 9% 높게 나타났고, 2.0% 밀도의 경우 강도는 각각 127, 45, 11% 높게 나타났다. 시험 결과 지름이 동일할 경우 밀도가 높을수록, 밀도가 동일할 경우 지름이 작을수록 보강효과가 더 높게 나타나는 것을 알 수 있었다. 요철핀과 일반핀의 효과를 비교한 결과 2.0% 밀도로 0.3 mm 직경의 핀을 이용하여 보강할 경우, 요철핀 보강시편이 일반핀 보강 시편보다 64% 높은 강도를 보였다. 본 연구의 결과로부터 요철핀 보강이 복합재 모자형 체결부의 풀오프 강도 향상을 위한 효과적인 방법이 될 수 있음을 확인하였다.