• Journal of the Ergonomics Society of Korea
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• v.28 no.3
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• pp.1-6
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• 2009

Recently, importance of the rehabilitation of hand pathologies as well as the development of high-technology hand robot has been increased. The biomechanical model of hand is indispensable due to the difficulty of direct measurement of muscle forces and joint forces in hands. In this study, a three-dimensional biomechanical model of four fingers including three joints and ten muscles in each finger was developed and a mathematical relationship between neural commands and finger forces which represents the enslaving effect and the force deficit effect was proposed. When pressing a plate under the flexed posture, the muscle forces and the joint forces were predicted by the optimization technique. The results showed that the major activated muscles were flexion muscles (flexor digitorum profundus, radial interosseous, and ulnar interosseous). In addition, it was found that the antagonistic muscles were also activated rather than the previous models, which is more realistic phenomenon. The present model has considered the interaction among fingers, thus can be more powerful while developing a robot hand that can totally control the multiple fingers like human.

• Journal of the Korea Society of Computer and Information
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• v.23 no.9
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• pp.1-6
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• 2018

In this paper, we propose a method dividing effectively the hand and fingers using general webcam. The method executes 4 times empirically preprocessing one to erase noise. First, it erases the overall noise of the image using Gaussian smoothing. Second, it changes from RGB image to HSV color model and YCbCr color model, executes a global static binarization based on the statistical value for each color model, and erase the noise through bitwise-OR operation. Third, it executes outline approximation and inner region filling algorithm using RDP algorithm and Flood fill algorithm and erase noise. Lastly, it erases noise through morphological operation and determines the threshold propositional to the image size and selects the hand and fingers area. This paper compares to existing one color based hand area division method and focuses the noise deduction and can be used to a gesture recognition application.

• Journal of the Ergonomics Society of Korea
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• v.22 no.2
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• pp.29-44
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• 2003

A variety of research has been conducted on anthropometric dimensions and their applications to various products and space architecture, Also robust research has been conducted on various parts of human body and the possibility of applications. However, research on the specific dimensions regarding fingers and characteristics of hands have rarely been conducted in Korea. In addition, except for the NASA Anthropometric Source Book that suggests measures for specific purposes such as gloves and hand-operated device, almost no literature can be found on this topic, The primary objective of this study was thus to provide anthropometric dimensions of Korean hands and fingers and recommend appropriate product design solutions for human hands. Six hundred Korean male and female subjects aging from 11 to 93 were selected, Thirteen different hands and fingers were measured along with demographic data(e.g., age, stature, weight} to determine the relationships among these obtained data, The results of this study should be considered in ergonomic design for every hand-used products and hand-operated control devices.

• Journal of Sensor Science and Technology
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• v.20 no.5
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• pp.351-356
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• 2011

Stroke patients should exercise for the rehabilitation of their fingers, because they can't use their hand and fingers. Their hand and fingers are fixed on the hand fixing system for rehabilitation exercise of them. But the hands clenched the fist of stroke patients are difficult to fix on it. In order to fix the hands and fingers, their palms are pressed with pressing bars and are controlled by reference force. The fixing system must have a five-axis force/moment sensor to force control. In this paper, the five-axis force/moment sensor was developed for the hand fixing system of finger-rehabilitation exercising system. The structure of the five-axis force/moment sensor was modeled, and designed using finite element method(FEM). And it was fabricated with strain-gages, then, its characteristic test was carried out. As a result, the maximum interference error is less than 2.43 %.

• Journal of Biomedical Engineering Research
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• v.40 no.3
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• pp.116-124
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• 2019

The rehabilitation training robots for treating the upper limbs of stroke patients were mainly focused on the upper proximal treatment of it, but recently studies of the distal parts of the upper limbs for rehabilitation of the hand is making some progress even though it is still a small number so far. In this paper, we present the hand robot for the rehabilitation training of stroke patients that is the fingertip contact-typed mechanism, and it has also equipped with the wrist rehabilitation unit to be worked like human hand that enables any movements through mutual cooperation by fingers while picking up or grasping objects. The robot that is presented for this purpose supports the movement of fingers with 5-DoF and the wrist with 3-DoF that moves independently, and operates with a structure that allows the joints of the wrist and fingers to be collaborated organically together to each other. Also, hereby the simulation and evaluation test on its robot mechanism are performed to ensure that fingers with 5-DoF and the wrist with 3-DoF of the serial kinematical mechanism are designed to comply with or exceed ROM for ADL.

• Archives of Reconstructive Microsurgery
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• v.16 no.1
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• pp.30-38
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• 2007

In acute hand injury, there are sometimes hattened neglected or overlooked vascular injury by primary operators. The authors evaluated the final results and prognosis after secondary revascularization. In eight cases, the authors performed secondary revascularization after prolonged warm ischemia. Five fingers in five cases among them were successfully survived and three cases finally necrosed. The mean warm ischemic time was 56.1 hours. In revascularization procedures, end-to-end artery anastomosis was possible in six cases. In two cases, vein graft was needed to anastomose digital artery, which resulted in complete survival of the fingers. In all three cases, revision amputation of the fingers was done. In acute complex hand injury, the importance of evaluation of the vascular injury can not be overemphasized. The necessity of the early secondary revascularization as well as serious consequence caused by misdiagnosis of vascular injury should be aware.

• Journal of the Korean Society of Industry Convergence
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• v.17 no.1
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• pp.21-26
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• 2014

The focus of this paper is the designing a flexible three fingered hand system with 16 D.O.F for dynamic manipulation with an intelligent controller, and to build a useful database for dynamic manipulation based on the experimental results. The weight of the hand module is only 0.7 kg, but flexible motion and powerful grasping are possible. To achieve such a dynamic motion in a robotic hand, we have developed a flexible fingered hand with a control system incorporating image recognition system in which we deal with the problems of not only accuracy and range of motion but also the flexibility of hand. The fingers are arranged so as to grasp both circular and prismatic objects. In order to achieve the light mechanism, we reduced the number of joints and fingers as much as possible. We used three fingers, which is the minimum number to achieve a stable grasp.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.6
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• pp.71-76
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• 2008

The focus of this paper is the designing a flexible three fingered hand system with 16 D.O.F for dynamic manipulation with an intelligent controller, and to build a useful database for dynamic manipulation based on the experimental results. The weight of the hand module is only 0.7 kg, but flexible motion and powerful grasping are possible. To achieve such a dynamic motion in a robotic hand, we have developed a flexible fingered hand with a control system incorporating image recognition system in which we deal with the problems of not only accuracy and range of motion but also the flexibility of hand. The fingers are arranged so as to grasp both circular and prismatic objects. In order to achieve the light mechanism, we reduced the number of joints and fingers as much as possible. We used three fingers, which is the minimum number to achieve a stable grasp.

• Journal of Sensor Science and Technology
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• v.19 no.5
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• pp.349-355
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• 2010

Stroke patients, etc. can't use their hands because of the paralysis of their fingers, and their fingers could be recovered by rehabilitating training. In order to judge the rehabilitating extent of their fingers, the patients should grasp a cylindrical object in hospital. At present, the used object in hospital is only a cylindrical object, and can't measure the force of fingers. Therefore, doctors judge the rehabilitating extent by touching and watching at their fingers. So, the four-finger force measuring system which can measure the force of their fingers should be developed. In this paper, four-finger force measuring system with four force sensors which can measure the grasping force is developed. The force sensors are designed and fabricated, and the force measuring device is designed and manufactured by using DSP(digital signal processing). Also, the grasping force test of men is performed by using the developed four-finger force measuring system. It was confirmed that the finger average force of right hand is about 214.6 N and that of left hand is about 212.8 N.

• Archives of Reconstructive Microsurgery
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• v.17 no.1
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• pp.51-54
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• 2008

We experienced a case of 49-year-old male patient with amputated two fingers preserved in Soju (Korean traditional liquor, a kind of alcoholic beverages). The amputation level of the two fingers was at the distal interphalangeal joint. The Soju was not an adequate physiologic solution for preserving the amputated tissues. Even though arterial anastomosis was successful, there was no venous drainage visible in the operative field. On the first day after the initial operation, we succeeded in the anastomosis of one vein in one of the two amputated fingers. This was 12 hours after arterial anastomosis was carried out. But no venous dranage was visible in the other finger. In spite of a salvage procedure sustained with external bleeding for 7 days, this replanted fingertip eventually fell into necrosis.