• Title/Summary/Keyword: Hand Fingers

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Personal Identification Using Inner Face of Fingers from Contactless Hand Image (비접촉 손 영상에서 손가락 면을 이용한 개인 식별)

  • Kim, Min-Ki
    • Journal of Korea Multimedia Society
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    • v.17 no.8
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    • pp.937-945
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    • 2014
  • Multi-modal biometric system can use another biometric trait in the case of having deficiency at a biometric trait. It also has an advantage of improving the performance of personal identification by using multiple biometric traits, so studies on new biometric traits have continuously been performed. The inner face of finger is a relatively new biometric trait. It has two major features of knuckle lines and wrinkles, which can be used as discriminative features. This paper proposes a finger identification method based on displacement vector to effectively process some variation appeared in contactless hand image. At first, the proposed method produces displacement vectors, which are made by connecting corresponding points acquired by matching each pair of local block. It then recognize finger by measuring the similarity among all the detected displacement vectors. The experimental results using pubic CASIA hand image database show that the proposed method may be effectively applied to personal identification.

Control Program for Dexterous Manipulation by Robotic Hand (물체의 안정한 조작을 위한 동작의 계획과 운동의 실현)

  • Hwang Chang-Soon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.4 s.235
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    • pp.540-554
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    • 2005
  • This paper presents a motion planning and control method for the dexterous manipulation with a robotic hand. For a given trajectory of an object, a simulation system calculates the necessary joint displacements and contact forces at the fingertip surfaces. These joint displacements and contact forces are the reference inputs to the control loops of the robotic fingers. A task is decomposed into a set of primitive motions, and each primitive motion is executed using the planned output of the simulation system as the reference. Force sensors and dynamic tactile sensors are used to adapt to errors and uncertainties encountered during manipulation. Several experimental results are presented.

Development of a General Purpose Motion Controller Using a Field Programmable Gate Array (FPGA를 이용한 범용 모션 컨트롤러의 개발)

  • Kim, Sung-Soo;Jung, Seul
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.1
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    • pp.73-80
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    • 2004
  • We have developed a general purpose motion controller using an FPGA(Field Programmable Gate Array). The multi-PID controllers and GUI are implemented as a system-on-chip for multi-axis motion control. Comparing with the commercial motion controller LM 629, since it has multi-independent PID controllers, we have several advantages such as space effectiveness, low cost and lower power consumption. In order to test the performance of the proposed controller, motion of the robot hand is controlled. The robot hand has three fingers with 2 joints each. Finger movements show that tracking was very effective. Another experiment of balancing an inverted pendulum on a cart has been conducted to show the generality of the proposed FPGA PID controller. The controller has well maintained the balance of the pendulum.

Development of prosthetic hand for detecting grasping force using underactuated mechanism (Underactuated mechanism 을 이용한 파지력 감지 전동의수 개발)

  • Jo, Seong;Jang, Dae-Jin;Baek, Yoon-Su;Yang, Hyun-Seok
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.858-863
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    • 2004
  • In this study, the new prosthetic hand which can perform sensory feedback is developed. Although the continuous development of current prosthetic hands, they have some drawbacks. The drawbacks are the low grasping capabilities, the lack of sensory information given to the user, and so on. Despite the improvement of the function of fingers, the sensory information problem still remains undeveloped. By using differential gear and underactuated mechanical design, it can be solved with the minimum additional weight. And it will be applied to all of the prosthetic hands.

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Finite motion analysis for multifingered robotic hand considering sliding effects

  • Chong, Nak-Young;Choi, Donghoon;Suh, Il-Hong
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10b
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    • pp.370-375
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    • 1992
  • An algorithm for the notion planning of the robotic hand is proposed to generate finite displacements and changes in orientation of objects by considering sliding effects between the fingertips and the object at contact points. Specifically, an optimization problem is firstly solved to find minimum contact forces and minimum joint velocities to impart a desired motion to the object at each time step. Then the instantaneous relative velocity at the contact point is found by determining velocities of the fingertip and the velocity of the object at the contact point. Finally time derivatives of the surface variables and contact angle of the fingertip and the object at the present time step is computed using the Montana's contact equation to find the contact parameters of the fingertip and the object at the next time step. To show the validity of the proposed algorithm, a numerical example is illustrated by employing the robotic hand manipulating a sphere with three fingers each of which has four joints.

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Venous Anastomosis with Dorsal Veins Using Additional Incisions after Wound Closure in Metacarpophalangeal Joint Level Replantation

  • Cho, Sang Hyun;Bahar-Moni, Ahmed Suparno;Whang, Jong Ick;Seo, Hyeung Gyo;Park, Hyun Sik;Kim, Ji Sup;Park, Hyun Chul
    • Archives of Reconstructive Microsurgery
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    • v.25 no.1
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    • pp.12-14
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    • 2016
  • In cases of replantation, accurate closure of all structures, including bone, tendons, arteries, nerves, and veins is essential. Among these, the vein is a weaker structure and is damaged severely in most amputation cases. After fixation of bone, repair of tendons, nerves, and arteries, surgeons often experience difficulty in performing venous anastomoses. We found that in such cases, venous anastomosis is easy to perform using an additional incision after closure of the original wound. In a 33-year-old male patient with amputation of all four fingers at the metacarpophalangeal joint level, venous anastomoses were performed with dorsal veins using additional incisions after completion of the fixation of bones and repair of all other structures and closure of the skin due to surgical site tension.

The Beau's Line Secondary to Acute Hand Injury (급성 수부 손상 후 발생한 보우선)

  • Kim, Tak Ho;Chung, Sung Mo;Lee, Nae Ho;Yang, Kyung Moo
    • Archives of Plastic Surgery
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    • v.33 no.5
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    • pp.652-654
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    • 2006
  • Beau first described transverse depressions of the fingernails after an acute febrile illness in 1846. It was the result of the temporary arrest of nail matrix formation. The transient interference of nail growth rate is usually induced by disability caused by severe systemic disease. Such as Raynaud disease, myocardial infarction, pulmonary embolism, acute renal failure, psoriasis and dysmenorrhea were reported to be the cause of Beau's line. The trauma caused either in a hand or in a forearm was also reported to be the cause of Beau's line. We experienced patients with Beau's line, two cases secondary to fingertip injury and one case due to fracture in radius. They had Beau's lines in all fingers of traumatized hand and nails of opposite hand were normal. During the follow-up, the growth rate of traumatized fingernails were normal and there was no complication.

Accelerating Distance Transform Image based Hand Detection using CPU-GPU Heterogeneous Computing

  • Yi, Zhaohua;Hu, Xiaoqi;Kim, Eung Kyeu;Kim, Kyung Ki;Jang, Byunghyun
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.5
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    • pp.557-563
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    • 2016
  • Most of the existing hand detection methods rely on the contour shape of hand after skin color segmentation. Such contour shape based computations, however, are not only susceptible to noise and other skin color segments but also inherently sequential and difficult to efficiently parallelize. In this paper, we implement and accelerate our in-house distance image based approach using CPU-GPU heterogeneous computing. Using emerging CPU-GPU heterogeneous computing technology, we achieved 5.0 times speed-up for $320{\times}240$ images, and 17.5 times for $640{\times}480$ images and our experiment demonstrates that our proposed distance image based hand detection is robust and fast, reaching up to 97.32% palm detection rate, 80.4% of which have more than 3 fingers detected on commodity processors.

Metastatic Tumor in Hand (수부에 발생한 전이암)

  • Rhee, Seung-Koo;Chung, Do-Hyun;Kong, Chae-Gwan;Kim, Jeong-Ho
    • The Journal of the Korean bone and joint tumor society
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    • v.9 no.2
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    • pp.155-161
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    • 2003
  • Skeletal metastasis are common in terminal malignant tumor patients over 30% of incidence, but hand acrometastasis are very rare under 0.1% in terminal cancer patients. We have reported 5 cases of hand acrometastasis herewith the review of literatures. In the preterminal malignant tumor patients, sudden painful swelling on fingers and osteoporosis on X-rays are thought to be the earliest sign of hand metastasis.

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The Effects of Constraint-Induced Movement Therapy on Improvement of Hand Function in Hemiplegic Side (Constraint-Induced Movement Therapy가 편마비측 손기능 증진에 미치는 영향)

  • Ryu, In-Tae;Hwang, Byong-Yong;Kim, Ji-Hye;Chung, Sang-Mi
    • The Journal of Korean Physical Therapy
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    • v.21 no.2
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    • pp.9-14
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    • 2009
  • Purpose: This study examined the effect of constraint-induced movement therapy (CIMT) on improving the hand function in hemiplegic side. Methods: Ten subjects without a control group were given CIMT to the hemiplegic side for 3 weeks. The effects of their hand function and sensibility were examined using a MAL and two point discrimination test. Repeated ANOVA was carried out for an analysis of the effects of the application of CIMT before and after treatment. Results: The participants showed significant improvement in their functional aspect with CIMT while there were no significant changes in the time domain variables. There was significant improvement in the quantitative and qualitative aspect of MAL, as well as significant improvement in the two-point discrimination function in all fingers. Conclusion: CIMT can enhance the motor function and sensory function of the hand in hemiplegic patients.

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