• Journal of Institute of Control, Robotics and Systems
• /
• v.18 no.10
• /
• pp.964-969
• /
• 2012

Robot hands capable of grasping or handling various objects are important for service robots to effectively aid humans. In particular, controlling a contact force and providing a compliant motion are essential when the hand is in contact with objects. Many dexterous robot hands equipped with force/torque sensors have been developed to perform force control, but they suffer from the complexity of control and high cost. In this paper, a low-cost robot hand based on SEA (Series Elastic Actuator), which is composed of compression spring, stretch sensor, and wire, is proposed. The grasping force can be estimated by measuring the compression length of spring, which would allow the hand to perform force control. A series of experimentations are carried out to verify the performance of force control of the proposed robot hand, and it is shown that it can successfully control the contact force without any additional force/torque sensors.

• Journal of Chest Surgery
• /
• v.23 no.4
• /
• pp.799-803
• /
• 1990

It is known that an interesting and unusual axillary artery thrombosis may develop over a period of time if an improperly adjusted crutch impinges repeatedly on the axilla. A 39 year-old male developed occlusion of left axillary artery and gangrenes of the left fingers after he had used axillary crutch for 25 years because of limping of the left leg resulting from poliomyelitis. The left hand was salvaged by successful thrombectomy. We report this case, review and discuss the literatures.

• 제어로봇시스템학회:학술대회논문집
• /
• 1990.10a
• /
• pp.52-56
• /
• 1990

An algorithm is proposed to determine the optimal contact forces of robotic hands, where the soft finger contact as well as the frictional point contact are considered. Especially, the algorithm can be efficiently applied to the case of multi-point contact by inner-link as well as fingertip. To show the validities of the algorithm, several numerical exampies are presented by employing a robotics hand with three fingers each of which has four joints.

• Journal of Korean Physical Therapy Science
• /
• v.6 no.2
• /
• pp.943-951
• /
• 1999

Thoracic outlet syndrome's chief symptom has numbness and tingling sensation of tharm, hand and fingers. In the morning, patient complain of pins and needles of the hands and weakness. TOS classified three categories : Anterior scalene syndrome, Claviculocostal syndrome, Pectoralis minor syndrome Physical therapy of the TOS is heat, massage for soft tissue, stretching exercise for scalene muscles and pectoralis minor muscles, and strengthening exercise for upper trapezius and levator scapular and neck muscles. A main problem of soft tissue is mechanical causes, so physical therapists have to solve that problem by mechanical manual methods.

• Journal of Internet Computing and Services
• /
• v.17 no.2
• /
• pp.29-37
• /
• 2016

Humans develop and maintain relationship through communication. Communication is largely divided into verbal communication and non-verbal communication. Verbal communication involves the use of a language or characters, while non-verbal communication utilizes body language. We use gestures with language together in conversations of everyday life. Gestures belong to non-verbal communication, and can be offered using a variety of shapes and movements to deliver an opinion. For this reason, gestures are spotlighted as a means of implementing an NUI/NUX in the fields of HCI and HRI. In this paper, using Kinect and the geometric features of the hand, we propose a method for recognizing the number of fingers and detecting the hand area. A Kinect depth image can be used to detect the hand region, with the finger number identified by comparing the distance of outline and the central point of a hand. Average recognition rate for recognizing the number of fingers is 98.5%, from the proposed method, The proposed method would help enhancing the functionality of the human computer interaction by increasing the expression range of gestures.

• PNF and Movement
• /
• v.18 no.1
• /
• pp.1-10
• /
• 2020

Purpose: This study was conducted to examine the effects of a PNF intervention using elastic bands on edema, range of motion (ROM), and pain in post-mastectomy patients with upper limb lymphedema, according to their hand grip type. Methods: The subjects were 14 female patients who were at Stage II lymphedema after undergoing mastectomy for Stage II breast cancer. They were randomly divided into an experimental group (n =7) and a control group (n = 7). Both groups participated in a treatment program four times (one time under the therapist's instructions and three times as self-exercise) a week for 4 weeks. Both groups repeated an upper limb PNF pattern exercise for 30 min using elastic bands after receiving a manual lymph drainage treatment for 1 hour. Here, subjects in the experimental group performed the PNF exercise with an open-hand grip by putting their hands into the loops of elastic bands and keeping their fingers spread out. Subjects in the control group performed the PNF exercise with a closed-hand grip by holding the loops of elastic bands with their fingers. In both groups, the subjects' edema, ROM, and pain levels were measured before the intervention and 2, 3 and 4 weeks after the intervention. Results: As a result of the experiment, both groups demonstrated edema reductions, ROM increases, and pain reductions in four areas of the upper limbs. Notably, the experimental group exhibited larger ROM increases in flexion, extension, and abduction as well as greater edema and pain reductions than the control group. In particular, the most significant effects were found in the elbow of the four upper limb areas for edema reductions and in extension for ROM increases. Conclusion: The present study indicates that exercise therapy-based approaches using elastic bands in post-mastectomy patients with upper limb lymphedema can have different effects depending on the type of hand grip (open or closed), which is the body's most distal part. Therefore, these approaches should be based on the conditions of the distal parts of the patient's body for their effective applications in clinical practice.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.25 no.10
• /
• pp.1323-1329
• /
• 2021

For hand expression recognition, hand pose recognition based on the static shape of the hand and hand gesture recognition based on the dynamic hand movement are used together. In this paper, we propose a hierarchical hand pose model based on finger position and shape for hand expression recognition. For hand pose recognition, a finger model representing the finger state and a hand pose model using the finger state are hierarchically constructed, which is based on the open source MediaPipe. The finger model is also hierarchically constructed using the bending of one finger and the touch of two fingers. The proposed model can be used for various applications of transmitting information through hands, and its usefulness was verified by applying it to number recognition in sign language. The proposed model is expected to have various applications in the user interface of computers other than sign language recognition.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.14 no.4
• /
• pp.506-511
• /
• 2004

Biometrics is getting more and more attention in recent years for security and other concerns. So far, only fingerprint recognition has seen limited success for on-line security check, since other biometrics verification and identification systems require more complicated and expensive acquisition interfaces and recognition processes. Hand-Geometry has been used for biometric verification and identification because of its acquisition convenience and good performance for verification and identification performance. Hence, it can be a good candidate for online checks. Therefore, this paper proposes a Hand-Geometry recognition system based on geometrical features of hand. From anatomical point of view, human hand can be characterized by its length, width, thickness, geometrical composition, shapes of the palm, and shape and geometry of the fingers. This paper proposes thirty relevant features for a Hand-Geometry recognition system. However, during experimentation, it was discovered that length measured from the tip of the finger was not a reliable feature. Hence, we propose a new technique based on Genetic Algorithm for extraction of the center of nail bottom, in order to use it for the length feature.

• The Journal of Korean Physical Therapy
• /
• v.18 no.5
• /
• pp.13-23
• /
• 2006

Purpose: This study was to investigate two-point discrimination(TPD) and related factors in rural community residents. Methods: The sample consisted of 68 people who have been living in rural community in June 2005 studied. TPD was measured from the tips of the thumb, index, middle, ring, and little finger of each hand with the TPD esthesiometer. The research was designed to be a cross-sectional measured study. SAS statistical software was used for the analysis. The characteristics of the study sample were described by mean and standard deviation(SD) for continuous variables and by frequency and percentage for categorical variables. The Student's t-test and analysis of variance (ANOVA) were used to compare TPD in gender and diabetes mellitus. A Pearson's correlation analysis was conducted for relationship among values of 5 fingers. Multiple regression analysis was performed to determine the factors associated with TPD. Results: A total of 68 residents were measured, their average $age{\pm}SD$ was $54.2{\pm}23.2$ years(range: $12{\sim}88\;yr$). The mean TPD for 5 fingers tips in dominated side was 4.76mm(thumb 3.98mm, index 4.22mm, middle 4.79mm, ring 5.17mm, and little finger 5.65mm, respectively). 4.91mm for thumb finger of women was significantly higher than 3.54mm that of men's in difference between gender(p=.01l4), also women(4.39mm) was higher than men(3.71mm) in median nerver area(p=.0318). There was a statistically significant difference in age(p=.0022), which were under age of 20(3.36mm), 30 years(3.61mm), 40 years(5.38mm), 50 years(4.84mm), 60 years(5.28mm), 70 years(5.18mm), and over age of 80(5.29mm). Factors related to TPD of fiver fingers by multiple regressions were gender(${\beta}=.03$, p=.0001). Conclusions: Taken together, gender and age were significantly associated with TPD. We recommend that further research should measure TPD by using larger sample sizes and more sensitive measurement instruments.

• Korean Journal of Applied Biomechanics
• /
• v.30 no.2
• /
• pp.131-144
• /
• 2020

Objective: The purpose of this study was to examine the effect of degrees of freedom on the multi-synergies in two hierarchies of human hand system during force production and releasing tasks. Method: In this study, the constrained movements of the aiming and releasing actions using both hands and fingers during archery-like shooting were implemented as experimental tasks. The participants produced a pulling force holding the customized frame (mimicking an archery bow, with a set of force transducers) and kept it consistently for about 5 seconds, and released fingers as quickly as possible in a self-paced manner within the next 5 seconds. An analytical method based on the uncontrolled manifold hypothesis was used to quantify the stability index (synergy index) in two hierarchies including two hands (upper hierarchy) and individual fingers (lower hierarchy). Results: The results confirmed that the positive synergy pattern showed simultaneously at the upper and lower hierarchies, and the kinetic degrees of freedom were associated with the increment of hierarchical synergy indices and the performance indices. Also, the synergy indices of both hierarchies showed significant positive correlations with the performance accuracy during the task. Conclusion: The results of this study suggest that the human control system actively uses extra degrees of freedom to stabilize task performance variables. Further increasing the degree of freedom at one level of hierarchy induces positive interactions across hierarchical control levels, which in turn positively affects the accuracy and precision of task performance.