• 소음진동
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• 제6권5호
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• pp.555-565
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• 1996

This paper is concerned with the theoretical and experimental study on the force control of a miniature robotic finger that grasps an object at three other positions with the fingertip. The artificial finger is a uniform flexible cantilever beam equipped with a distributed set of compact grasping force sensors. Control action is applied by a piezoceramic bimorph strip placed at the base of the finger. The mathematical model of the assembled electro- mechanical system is developed. The distributed sensors are described by a set of concentrated mass-spring system. The formulated equations of motion are then applied to a control problem in which the finger is commanded to grasp an object. The H$_{\infty}$-controller is introduced to drive the finger. The usefulness of the proposed control technique is verified by simulation and experiment..

• 한국정밀공학회지
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• 제13권9호
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• pp.94-103
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• 1996

This paper is concerned with the theroretical and experimental study on the force control of a miniature robotic finger that grasps an object at three other positions with the fingertip. The artificial finger is uniform flexible cantilever beam equipped with a distributed set of compact grasping force secnsors. Control action is applied by a qiexoceramic bimorph strip placed at the base of the finger. The mathematical model of the assembled electro-mechanical system is developed. The distributed sensors are described by a set of concentrated mass-spring system. The formulated equations of motion are then applied to a control problem which the finger is commanded to grasp an object The PID-controller is introduced to drive the finger. The usefulness of the proposed control technique is verified by simulation and experiment.

• 대한기계학회논문집A
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• 제39권9호
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• pp.831-837
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• 2015

사람과 전자기기들은 우리 주변의 환경 속, 특히 병원의 자기 공명 영상(Magnetic resonance imaging, MRI) 장비 또는 군용으로 사용되는 전자기 펄스(Electromagnetic pulse, EMP) 장비, 그리고 수많은 전자파를 만들어 내는 장치들에 노출되는 경우가 잦아졌다. 이러한 전자파는 사람과 전자기기에 유해하고, 이를 차폐하기 위해 사용되는 것 중에 하나가 핑거 스트립이다. 핑거 스트립은 열전도성이 좋기 때문에 전자파를 흡수하여 열로 변환한다. 이 특징을 효과적으로 이용하여 전자파 차폐가 필요한 실내의 특수 문짝에 핑거 스트립을 설치해서, 전자파로부터 사람과 전자기기들을 보호한다. 본 연구에서는 핑거 스트립의 주 고장모드에 영향을 주는 가속인자로 하중을 선택하여 가속수명시험을 실시한다. 가속수명시험의 결과로부터 핑거 스트립의 실사용조건 수명을 예측하며, 동일한 조건에서 실시한 수명 시험 결과와 비교하여 가속수명시험의 유효성을 평가하고자 하였다.

• Tribology and Lubricants
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• 제28권5호
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• pp.240-245
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• 2012

In this study, we developed a new carrier finger to prevent scratches in a sheet metal forming line. The developed carrier finger was designed to have a streamlined shape with a larger radius of curvature at the edges, as well as a smaller contact area. To evaluate the scratch alleviation effect, a sliding contact analysis and scratch test using the pin on a plate wear tester were conducted for both the old and new carrier fingers. The results show that, for both transverse and longitudinal movements of the strip, the newly designed carrier finger reduces both the friction and scratch depth by its streamlined shape, which decreases the pressure spike at the edge.

• 한국의류산업학회지
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• 제24권3호
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• pp.333-345
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• 2022

This study developed and evaluated the motion control of 3D printed fingers applied to smart gloves. Four motions were programmed by assembling the module using the Arduino program: cylindrical grasping, spherical grasping, tip-to-tip pinch gripping, and three-jaw pinch gripping. Cap and re-entrant (RE) strip types were designed to model the finger. Two types of modeling were printed using filaments of thermoplastic elastomer (TPE) and thermoplastic polyurethane (TPU). The prepared samples were evaluated using three types of pens for cylidrical grasping, three types of balls for spherical grasping, and two types of cards for tip-to-tip pinch gripping and three-jaw pinch gripping. The motion control of fingers was connected using five servo motors to the number of each control board. Cylindrical and spherical grasping were moved by controlling the fingers at 180° and 150°, respectively. Pinch gripping was controlled using a tip-to-tip pinch motion controlled by the thumb at 30° and index-middle at 0° besides a three-jaw pinch motion controlled by the thumb-index finger-middle at 30°, 0°, and 0°, respectively. As a result of the functional evaluation, the TPE of 3D-printed fingers was more flexible than those of TPU. RE strip type of 3D-printed fingers was more suitable for the motion control of fingers than the 3D-printed finger.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1808-1813
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• 2005

In this paper, we present the finger tip tactile sensor which can detect contact normal force as well as slip. The developed sensor is made of two different materials, such as polyvinylidene fluoride(PVDF) that is known as piezoelectric polymer and pressure variable resistor ink. In order to detect slip to surface of object, a PVDF strip is arranged along the normal direction in the robot finger tip and the thumb tip. The surface electrode of the PVDF strip is fabricated using silk-screening technique with silver paste. Also a thin flexible force sensor is fabricated in the form of a matrix using pressure variable resistor ink in order to sense the static force. The developed tactile sensor is physically flexible and it can be deformed three-dimensionally to any shape so that it can be placed on anywhere on the curved surface. In addition, we developed a tactile sensing system by miniaturizing the charge amplifier, in order to amplify the small signal from the sensor, and the fast signal processing unit. The sensor system is evaluated experimentally and its effectiveness is validated.

• 대한기계학회논문집A
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• 제38권10호
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• pp.1171-1177
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• 2014

전자파차폐용 문세트는 기계적 강도 및 내구성과 전자파 차폐라는 전기적 성능 요구를 동시에 충족시켜야 하므로 이에 알맞은 신뢰성입증시험법의 정립이 요구된다. 특히 전자파 차폐 성능에 직접적인 영향을 미치는 핑거스트립이라고 불리는 베링륨동 재질의 박형 스프링 하위 부품은 문짝과 직접적인 반복 건조마찰이 발생하므로 내구성에 만전을 기해야 하는 부위인데, 산업계에서는 주기적인 보전이 필요한 이 핑거스트립의 교체주기에 대한 보증도 또한 필요한 실정이다. 이러한 요구들에 대응하여 본 연구에서는 전자파차폐용문세트의 시험항목들을 정하고 전체 시스템 수명뿐만 아니라 교체품의 교체주기에 대한 보증을 단순한 방법으로 동시수행하는 입증시험을 설계하였다. 결론적으로 하위 교체부품을 가지는 직렬 시스템의 신뢰성입증시험에서는 교체품의 교체주기에 대한 보증도 항상 함께 포함시킬 것을 제안한다.

• 대한기계학회논문집A
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• 제30권4호
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• pp.364-372
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• 2006

In this paper, we present a finger tip tactile sensor which can detect contact normal force as well as slip. The sensor is made up of two different materials, such as polyvinylidene fluoride (PVDF) known as piezoelectric polymer, and pressure variable resistor ink. In order to detect slip on the surface of the object, two PVDF strips are arranged along the normal direction in the robot finger tip and the thumb tip. The surface electrode of the PVDF strip is fabricated using silk-screening technique with silver paste. Also a thin flexible force sensor is fabricated in the form of a matrix using pressure variable resistor ink in order to sense the static force. The developed tactile sensor is physically flexible and it can be deformed three-dimensionally to any shape so that it can be placed on anywhere on the curved surface. In addition, a tactile sensing system is developed, which includes miniaturized charge amplifier to amplify the small signal from the sensor, and the fast signal processing unit. The sensor system is evaluated experimentally and its effectiveness is validated.

• 전자공학회논문지SC
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• 제45권5호
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• pp.28-34
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• 2008

유비쿼터스 헬스케어 환경의 실현을 위해 실시간의 생체 정보 모니터링은 매우 중요한 요소이다. 이러한 생체 정보 모니터링을 위한 장치는 대부분 PPG 신호를 얻어 피측정자의 상태 모니터링에 활용하고 있다. PPG 신호를 얻기 위해서는 핑거프로브를 손가락에 착용해야 하기 때문에 일상생활을 하기에 불편할 뿐만 아니라, 핑거 프로브 착용자의 움직임에 의한 동잡음으로 인하여 정확한 PPG신호를 얻기가 매우 힘들다. 본 논문에서는 핑거프로브를 없앤 U-헬스케어를 위한 손목형 생체 정보 모니터링 시스템을 개발하고, 생체 정보 모니터링 시스템의 감시 요소 중 하나인 PPG 신호의 동잡음 제거를 위해 새로운 알고리즘을 제안한다. 개발한 시스템은 핑거프로브를 없앤 대신 밴드스트립에 LED와 포토센서를 장착하여 손목의 동맥혈관의 혈류 변화량으로부터 PPG를 얻도록 설계하였다. 그러나 밴드스트립에 위치한 센서는 핑거프로브에 위치한 센서에 비해 많은 동잡음에 노출되어 있으므로, 그 동잡음들을 제거하기 위하여 최근 제기된 PPG 신호의 유사 주기성을 이용한 PMAF(Periodic Moving Average Filter) 방법을 개선한 새로운 동잡음 제거 방법을 제안한다.

• Reproductive and Developmental Biology
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• 제33권3호
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• pp.183-187
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• 2009

This study analyzed change of proteins in granulosa cells during the porcine follicuar development by proteomics techniques. Granulosa cells of the follicles, of which the diameter is $2{\sim}4\;mm$ and $6{\sim}10\;mm$, were collected from ovary of slaughtered pig that each follicle of diameter $1{\sim}4\;mm$ and $6{\sim}10\;mm$. We extracted glanulosa cell proteins by M-PER Mammalian Protein Extraction Reagent. Proteins were refined by clean-up kit and quantified by Bradford method until total protein was $200{\mu}l$. Immobilized pH gradient(IPG) strip used 18 cm, $3{\sim}10\;NL$. SDS-PAGE used 10% acrylamide gel. After silver staining, Melanie 7 and naked eye test were used for spot analyzation. Increasing proteins in glanulosa cell of $6{\sim}10\;mm$ follicle were 7 spots. This spots were analyzed by MALDI-TOF MS and searched on NCBInr. In results, 7 spots were similar to zinc/ling finger protein 3 precursor (RING finger protein 203), angiomotin, heat shock 60 kDa protein 1 (chaperonin) isoform 1 (HSP60), similar to transducin-like enhancer protein 1 (TLE 1), SH3 and PX domains 2A (SH3PXD2A). Those proteins were related with transfer between cells. Increase of proteins has an effect on follicular development.