• Journal of the Korean Wood Science and Technology
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• 제39권2호
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• pp.172-178
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• 2011

Three different finger-jointed lumbers which have different geometric features and adhesives were manufactured and studied in this study. Larch and pitch pine lumbers with and without preservative treatment were used. Bending MOE was measured as the preliminary investigation for grouping the specimen. After the finger, bending MOE of two wood species without preservative treatment shows over 97% property of the control group. The tensile modulus also shows almost same property after the finger joint. And it is found out that the preservative treatment induce little effect on bending and tensile MOE. Based on this result, high performance of examined finger-jointed lumber can be found out. However, tensile strength decreased around 20% which would be induced by the crack along the root of the finger which is formed near the edge during manufacturing stage. And finger-jointed lumber with preservative treatment even shows higher decrement of the tensile strength with higher wooden part failure mode.

• 대한인간공학회지
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• 제18권2호
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• pp.103-120
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• 1999

The purpose of this study was to evaluate the manual workload in repetitive wrist and finger motion. To evaluate manual workload, angular displacement of the joint, EMG of the muscle and subjective rating were studied. Both wrist motion and finger motion were studied. A screw-driving task was used for the wrist motion experiment. A keyboard typing task was used for the finger motion experiment. All finger joint angles and wrist angles were measured by an angle-measuring glove($CyberGlove^{TM}$, Virtual Technologies, Inc.). Surface EMG was recorded from FCU muscle and FDS muscle simultaneously with the angle measurement. Subjective ratings of exertion were also recorded using the modified Borg's CR-10 scale. Repetition rates of 0.5, 1, 2 motions per second were used with each task. As a result, manual workload increased with increasing repetitiveness. Peak spectral magnitude and frequency components corresponded closely with joint angular displacement amplitudes and repetition rates. Results of the correlation analysis showed that there were significant correlation among EMG, frequency-weighted motion and subjective measurement. Both EMG and frequency-weighted filtering showed consistent workload estimation with increasing task frequency. Subjective ratings showed slight over-estimation of the workload as the task frequency is increased.

• 한국정밀공학회지
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• 제16권1호통권94호
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• pp.42-48
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• 1999

A control method for a robot hand grasping a object in a partially unknown environment will be proposed, where a proximate sensor detecting the distance between the fingertip and object was used. Particularly, the finger joints were driven servo-pneumatically in this study. Based on the proximate sensor signal the finger motion controller could plan the grasping process divided in three phases ; fast aproach, slow transitional contact and contact force control. That is, the fingertip approached to the object with full speed, until the output signal of the proximate sensor began to change. Within the perating range of the proximate sensor, the finger joint was moved by a state-variable feedback position controller in order to obtain a smooth contact with the object. The contact force of fingertip was then controlled using the blocked-line pressure sensitivity of the flow control servovalve for finger joint control. In this way, the grasping impact could be reduced without reducing the object approaching speed. The performance of the proposed grasping method was experimentally compared with that of a open loop-controlled one.

• Archives of Plastic Surgery
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• 제49권6호
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• pp.760-763
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• 2022

The dorsal metacarpal artery perforator flap is a flap that rises from the hand dorsum. Owing to its reliability and versatility, this flap is used as a workhorse for finger defect. However, to cover the radial-volar defect of the proximal interphalangeal joint (PIPJ) of the index finger, a longer flap is required than before. Here, we introduce the oblique extended reverse first dorsal metacarpal artery (FDMA) perforator flap to cover the radial-volar aspect defect of the index finger. A 45-year-old man got injured to the radial-volar defect of PIPJ of the left index finger caused by thermal press machine. The wound was 2 × 1 cm in size, and the joint and bone were exposed. We used FDMA perforator from anastomosis with palmar metacarpal artery at metacarpal neck. Since the defect was extended to the volar side, the flap was elevated by oblique extension to the fourth metacarpal base level. The fascia was included to the flap, and the flap was rotated counterclockwise. Finally, PIPJ was fully covered by the flap. Donor site was primarily closed. After 12 months of operation, the flap was stable without complication and limitation of range of motion. The oblique extended reverse FDMA perforator flap is a reliable method for covering the radial-volar defect of the PIPJ of the index finger. This flap, which also has an aesthetic advantage, will be a good choice for hand surgeons who want to cover the PIPJ defect of the index finger using a nonmicrosurgical option.

• 대한정형외과스포츠의학회지
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• 제8권1호
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• pp.51-55
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• 2009

수지 근위 지관절의 전방 회전 탈구는 매우 드물게 발생한다. 저자들은 여자 유도 선수에서 발생한 수지 근위 지관절의 전방회전 탈구를 경험하였기에 이를 문헌고찰과 함께 보고하고자 한다. 24세 여자 유도 선수로 총 4번의 근위 지관절 전방 탈구가 발생하였다. 수술 시 회전 손상으로 파열된 척측 측부 인대와 파열 없이 늘어져 있는 중앙 건을 확인할 수 있었다. 수술적 치료로 파열된 척측 측부 인대 봉합술과 중앙 건과 측부대 사이를 봉합하여 근위 지관절의 배측부를 강화 시켜주었다. 술 후 운동시에 탈구는 다시 발생하지 않았다. 수지 근위 지관절의 전방 회전 탈구는 매우 드문 손상이지만 다른 탈구처럼 조기 진단과 치료, 그리고 단계적인 재활이 무엇보다 중요하겠다.

• 재활복지공학회논문지
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• 제8권4호
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• pp.233-238
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• 2014

본 논문에서는 손재활기기를 평가하고 신뢰도 높은 검진을 위해 검진자의 훈련용으로 사용할 수 있는 손가락 모사 로봇을 개발하였다. 먼저 실제 사람의 손가락 크기를 고려하여 손허리가락 관절(Metacarpophalangeal)과 첫마디뼈 관절 (Proximal Interphalangeal)을 구동할 수 있는 메커니즘을 설계하였고 이를 통해 뇌졸중과 같은 신경 손상 환자들에게서 나타나는 경직(spasticity)과 구축(contracture)현상을 모사하는 알고리즘을 구현하여 경직과 구축의 정도를 조절하여 다양한 환자들의 특징을 구현할 수 있도록 하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.876-881
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• 2003

This study focused on to design and toanalysis of a myoelectronic hand. We considered a low frequency factor in human life and to quantify low frequency which a human body responded to using a 1-axis ant a 3-axis accelerometer. The dynamic myoelectronic hand are important for tasks such a continuous prosthetic control and a EMG signal recognition, which have not been successfully mastered by the most neural approached To control myoelectronic hand, classifying myoelectronic patterns are also important. Experimental results of FEM are 110㎫ on Thumb, 200㎫ on Index finger, 220㎫ on Middle finger 260㎫ on Ring finger and 270㎫ on Little finger. Experimental results of accelerometer are 1.4-0.4(m/s2) ,(5-20(〔Hz〕) in Feeding activity and 0.4-0(m/s2) (0-10〔Hz〕) in Lifting activity. Considering these facts, we suggest a new type myoelectronic hand.

• 한국정밀공학회지
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• 제15권12호
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• pp.142-147
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• 1998

Developing robot hands with multi-degree-of-freedom is one of the topics that researchers have recently begun to improve the limitation by adding flexibility and dexterity. In this study, an articulated servo-pneumatic robot hand system with direct-drive joints has been developed whose main feature is the minimization of the dimension. The servo-pneumatic system is advantageous to fabricate a dexterous robot hand system due to the high torque-to-weight and torque-to-volume ratio. This enables the design of a finger joint with an integrated rotary vane type actuator which produces high output torque without reduction gears, being very robust. In order to control the servo-pneumatic finger joints, a miniature proportional valve that can be attached to the robot hand is required. In this paper, a flapper nozzle type 4/3-way proportional directional valve has been designed and tested. The experimental results show that the developed valve can control a finger joint satisfactorily without much vibratory joint movements and acoustic noises.

• 한국가구학회지
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• 제12권2호
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• pp.1-10
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• 2001

As finger joint method has a high rate of yield and high strength and ease in working, it has been widely used as an end joint method for solid wood and wood based-material. Therefore, we end-joined the material of Pinus densiflora, Quercus variabilis and populus euramericana with polyvinyl acetate adhesive and resorcinol phenol resin adhesive. The effect of difference (0, 0.15, 0.3, 0.45mm) between the dimensions of tip width and root width of the finger (DTRW) on bending strength properties was as follows: 1. In the case of polyvinyl acetate adhesive, DTRW had no effect on bending modulus of elasticity(MOE) and modulus of rupture(MOR) of the three kinds of species, because their bonding layers were destroyed by slippage, not their woody parts. 2. In the case of resorcinol phenol resin adhesive, the material of Quercus variabilis showed an optimal result at 0.15 or 0.3 of DTRW, while the poplar did at 0 of DTRW 3. The differences in efficiency ratio of bending MOR of populus euramericana, Pinus densiflora and Quercus variabilis species according to the kind of adhesive were 13-29%, 23-30% and 45-53%, respectively.

• Archives of Plastic Surgery
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• 제36권3호
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• pp.318-321
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• 2009

Purpose: The bony mallet finger injury is generally managed by conservative treatments, but operative treatments are needed especially when the fractures involve above 30% of articular surface or distal phalanx is accompanied by subluxation in the volar side. This is the reason they often result in chronic instability, articular subluxation and unsatisfactory cosmetic. In this report, We describe new method using the hook plate as an operative treatment of Mallet finger deformity. Methods: Among 13 patients with Mallet finger deformity who came from February 2006 to February 2008, six patient were included in surgical indication. Under local anesthesia, H or Y type incision was made at the DIP joint area. After the DIP joint extension, the hook plate was put on the fracture line, and one self tapping screw was used for fixation. 2 hole plate which was one of the holes in 1.5 mm diameter was cut in almost half and bended through approximately $100^{\circ}$. Results: In all six cases which applied the hook plate, complications such as loss of reduction or nail deformity were not seen. In only one patient, hook pate was removed due to inflammatory reaction after surgery. At 2 weeks after operation, active motion of DIP joint was performed. The result was satisfactory not only cosmetically but also functionally. At 6 weeks after operation, the range of motion of DIP joint was average $64^{\circ}$. Conclusion: The purpose of the operative treatment for mallet finger deformity using the hook plate is to provide anatomical reduction with rigid fixation and to prevent contracture at the DIP joint. While other operations take 6 weeks, the operation using the hook plate begins an active motion at 2 weeks after operation. Complication rate was low and the method is rather simple. Thus, the operation using the hook plate is recommended as a good alternative method of the mallet finger deformity treatment.