• Proceedings of the KOSOMBE Conference
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• v.1991 no.05
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• pp.71-73
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• 1991

In this study electrical impedance plethysmograph was developed and each ten digital blood flow was measured for eight normal males and a patint with digital arterial reconstruction surgery. Blood flow of the digit with surgery was approximately fourty percent compared to that of the other normal digit. For the normal subjects, right-handed subjects generally have larger blood flow in right fingers than that in left fingers while it was reverse for the left-handed subjects. The relative average magnitude of the digital blood flow is the third, first, second, fourth, and fifth digit in descending order for the left and right hand, respectively. Blood flow of the fifth digit for all subjects except one was the smallest among the five digits.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1994-1999
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• 2003

This paper discusses dynamic characteristics of motion of a pair of multi-degrees of freedom robot fingers executing grasp of a rigid object and controlling its orientation with the aid of rolling contacts. In particular, the discussions are focused on a problem of gain-tuning of sensory feedback signals proposed from the viewpoint of sensorymotor coordination, which consist of a feedforward term, a feedback term for controlling rotational moment of the object, and another term for controlling its rotational angle. It is found through computer simulations of the overall fingersobject dynamics subject to rolling contact constraints that some dynamic characteristics of torque-angular velocity relation may play an important role likely as reported by experimental results in muscle physiology and therefore selection of damping gains in angular velocity feedback depending on the guess of object mass is crucial. Finally, a guidance of gain-tuning in each feedback term is suggested and its validity is discussed by various computer simulations.

• Journal of Biomedical Engineering Research
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• v.12 no.1
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• pp.23-28
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• 1991

In this study electrical impedance plethysmograph was developed and each ten digital blood flow was measured for eight nomal males and a patient tvith digital arterial reconstruction surgery. Blood flow of the digit with surgery was approximately fourty percent compared to that of the other normal digit. For the normal subjects, right - handed subjects generally have larger blood flow in right fingers than that in left fingers while it was reverse for the left - handed subjects. The relative average magnitude of the digltal blood flow Is the third, first, second, fourth, and fifth digit in descending order for the left and rich hand, respectively. Blood flow of the fifth digit for all subjec!s except one was the smallest among the five digits.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.4
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• pp.233-238
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• 2014

In this paper, we developed a finger robot simulating spasticity and contracture which can be used as a testing bed for evaluating performance of hand rehabilitation devices while it can be also used to train clinicians for improving reliability of clinical assessment. The robot is designed for adult finger size and for independent control of Metacarpophalangeal Joint and Proximal Interphalangeal Joint. Algorithm for mimicking spasticity and contracture is implemented. By adjusting the parameters related to contracture and spasticity, the robot can mimic various patterns of responses observed in fingers with spasticity and contracture.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1995.10b
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• pp.85-91
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• 1995

This paper presents a system which recognizes the Korean Sign Language(KSL) and translates into normal Korean speech. A sign language is a method of communication for the deaf-mute who uses gestures, especially both hands and fingers. Since the human hands and fingers are not the same in physical dimension, the same form of a gesture produced by two signers with their hands may not produce the same numerical values when obtained through electronic sensors. In this paper, we propose a dynamic gesture recognition method based on feature analysis for efficient classification of hand motions, and on a fuzzy min-max neural network for on-line pattern recognition.

• Journal of IKEEE
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• v.18 no.2
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• pp.291-297
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• 2014

Since hand gesture recognition was realized thanks to improved image processing algorithms, sign language translation has been a critical issue for the hearing-impaired. In this paper, we extract human hand figures from a real time image stream and detect gestures in order to figure out which kind of hand language it means. We used depth-color calibrated image from the Kinect to extract human hands and made a decision tree in order to recognize the hand gesture. The decision tree contains information such as number of fingers, contours, and the hand's position inside a uniform sized image. We succeeded in recognizing 'Hangul', the Korean alphabet, with a recognizing rate of 98.16%. The average execution time per letter of the system was about 76.5msec, a reasonable speed considering hand language translation is based on almost still images. We expect that this research will help communication between the hearing-impaired and other people who don't know hand language.

• The Journal of Korea Robotics Society
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• v.5 no.2
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• pp.102-109
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• 2010

In this study, an anthropomorphic robot Hand, called "SKKU Hand III" is presented. The hand has thirteen DOF(Degree-Of-Freedom) and is designed based on the skeletal structure of the human hand. Each finger module(except thumb module) has three DOF and four joints with a saddle joint mechanism which has two DOF at the base joint. Two distal joints of the finger module are mechanically coupled by a timing belt and pulleys. The thumb module is composed of a finger module and an additional actuator, which makes it possible to realize the opposition between the thumb and the other fingers. In addition, the palm DOF of the human hand is mimicked with a spatial link mechanism between the index finger and the thumb. Thus, it can grasp objects more stably and more strongly. For the modularization of the robotic hand all the driving circuits are embedded in the hand, and only the communication lines supporting CAN protocol with DC power cable are given as an interface. Therefore, it is possible to apply it to any robot system the interface. To validate the feasibility of the SKKU Hand III, a series of the representative grasp experiments such as power, precision, intermediate grasp etc. are carried out with the object around us and its operation is demonstrated.

• Archives of Reconstructive Microsurgery
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• v.25 no.2
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• pp.25-28
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• 2016

Purpose: Reconstruction of small defects of the dorsal fingers and toes is a challenging task. Although adipofascial flap is widely used for these areas, additional refinements are warranted. In this paper, we define the appropriate defect size in the finger and toes that can be treated with the adipofascial flap, refine its surgical indications and present a few surgical tips. Materials and Methods: Twelve patients with dorsal defects of the fingers and toes were treated with a random-type adipofascial turn-over flap and skin graft. If the defect area exceeded the size that could be covered by a conventional design, the flap base was designed in oblique or curvilinear fashion to lengthen the flap. For accurate defect coverage, the width of the flap base was designed in an asymmetrical shape depending on the defect configuration, varying the width from 0.3 to 1.0 cm, as opposed to the standard 0.5 to 1.0 cm width. Moreover, the lateral limit of the flap was defined as the lateral axial line. The size of the defect ranged from $3.0{\times}1.7cm$ to $1.5{\times}1.3cm$. Results: All flaps survived completely. Gliding function of the hand was well preserved and there was no evidence of tendon adhesion. Conclusion: The small defect in the dorsal finger and toe can be defined as less than one phalanx-length, measuring about $3.0{\times}2.0cm$ in size. If the defect exceeds this dimension, it is recommended that a different option be considered. We believe the adipofascial flap is an excellent option for treating small defects.

• Journal of the Ergonomics Society of Korea
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• v.18 no.3
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• pp.179-186
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• 1999

This article aims to provide information necessary for the measurement and analysis of human vibration, especially hand-arm vibration. The major health problems associated with the use of powered hand tools are the signs and symptoms of peripheral vascular and peripheral neural disorders of the fingers and hands. To prevent these problems, it is the first and the most important to measure the amount of the vibration transmitted to the upper extremities, and analyze its characteristics against the exposure limits such as ISO standards. In our country, however, very few studies have been done on the hand-arm vibration. One of the possible reasons might be lack of knowledge for the measurement and analysis schemes. The information introduced in this article would hopefully be of help for the upcoming studies.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.10
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• pp.919-926
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• 2010

This paper proposes a wearable hand rehabilitation device, DULEX, for persons with functional paralysis of upper-limbs after stoke. DULEX has three degrees of freedom for rehabilitation exercises for wrist and fingers except the thumb. The main function of DULEX is to extend the range of motions of finger and wrist being contracture. DULEX is designed by using a parallel mechanism, and its parameters such as length and location of links are determined by kinematic analysis. The motion trajectory of the designed DULEX is aligned to human hand to prevent a slip. To reduce total weight of DULEX, artificial air muscles are used for actuating each joint motion. In feedback control, each joint angle is indirectly estimated from the relations of the input air pressure and the output muscle length. Experimental results show that DULEX is feasible in hand rehabilitation for stroke survivals.