• Journal of Korea Society of Industrial Information Systems
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• v.17 no.4
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• pp.9-15
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• 2012

This paper presents application of a new tactile slippage sensation algorithm in robot hand control system. The optical three-axis tactile sensor is a type of tactile sensor capable of defining normal and shear forces simultaneously. The tactile sensor is mounted on fingertip of robotic hand. Shear force distribution is used to define slippage sensation in the robot hand system. Based on tactile slippage analysis, a new control algorithm was proposed. To improve performance during object handling motions, analysis of slippage direction is conducted. The control algorithm is classified into two phases: grasp-move-release and grasp-twist motions. Detailed explanations of the control algorithm based on the existing robot arm control system are presented. The experiment is conducted using a bottle cap, and the results reveal good performance of the proposed control algorithm to accomplish the proposed object handling motions.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.6
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• pp.594-599
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• 2006

In this paper an anthropomorphic robot hand called SKKU Hand IIl is presented, which has a miniaturized fingertip tactile sensor. The thumb is designed as one part of the palm and multiplies the mobility of the palm. The fingertip tactile sensor, based on polyvinylidene fluoride (PVDF) and pressure variable resistor ink, is physically flexible enough to be deformed into any three-dimensional geometry. In order to detect incipient slip, a PVDF strip is arranged along the direction normal to the surface of the finger of the robot hand. Also, a thin flexible sensor to sense the static force as well as the contact location is fabricated into an arrayed type using pressure variable resistor ink. The driving circuits and the tactile sensing systems for the SKKU Hand II are embedded in the hand. Each driving circuit communicates with others using CAN protocol. SKKU Hand II is manufactured and its feasibility is validated through preliminary experiments.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.8
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• pp.831-838
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• 2009

This paper proposes an IR (infrared) LED (Light Emitting Diode)-based tactile fingertip sensor that can independently measure the normal and tangential force between the hand and an object. The proposed IR LED-based tactile sensor has several advantages over other technologies, including a low price, small size, and good sensitivity. The design of the first prototype is described and some experiments are conducted to show output characteristics of the proposed sensor. Furthemore, the effectiveness of the proposed sensor is demonstrated through anti-slip control in a multifunction myoelectric hand, called the KNU Hand, which includes several novel mechanisms for improved grasping capabilities. The experimental results show that slippage was avoided by simple force control using feedback on the normal and tangential force from the proposed sensor. Thus, grasping force control was achieved without any slippage or damage to the object.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.12
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• pp.1138-1144
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• 2013

This paper proposes a tactile transfer and display method between a data glove and vibration motors module. The data glove is developed to capture the hand postures and to measure the grip forces. The measured data are simplified with the proposed 5-bit transfer and display algorithm, and the vibration motors module is developed to display the measured hand posture and grip force to the operator. The proposed 5-bit algorithm contains both an 8-step hand posture and 4-step grip force level information for tactile transfer to the vibration motors module. Also, the effectiveness of the proposed method is shown through several experiments.

• The Journal of Korean Physical Therapy
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• v.20 no.1
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• pp.75-79
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• 2008

Purpose: The purpose of this study was to investigate the effect of $\alpha$-wave music and art appreciation on hand function. Methods: A total of 22 university students participated in this study (10 males and 12 females). Twelve subjects received $\alpha$-wave music and art appreciation. The other subjects received neither. All subjects were assessed for hand function (manual dexterity, power grip, pinch, lateral pinch, tactile sense) using a Purdue pegboard, dynamometer, pinch gauge, and Semmes-Weinstein monofilament wire. The data were analyzed using paired and independent t-tests. Results: The results were as follows: 1. In the experimental group, manual dexterity and tactile sense were significantly increased between pre- and post-intervention (p<0.05). Within the control group, manual dexterity and power grip were significantly increased between pre- and post-test (p<0.05). 2. With regard to dexterity and tactile sense, the experimental group experienced a significant post-intervention increase compared to the control group (p<0.05). There was no significant difference in power grip, pinch, or lateral pinch changes between the two groups (p>0.05). Conclusion: The results of this study show that $\alpha$-wave music and art appreciation affect hand function with regard to manual dexterity and tactile sense.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.97.6-97
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• 2002

In this paper, we present an arrayed flexible tactile sensor, which can detect contact normal forces as well as positions. The tactile sensor is developed using Polyvinylidene Fluoride (PVDF) that is known as piezoelectric polymer, and the surface electrode is fabricated using silk-screening technique with silver. We develop a charge amplifier in order to amplify the small signal from the sensor, and a fast signal processing unit by using a DSP chip. The developed tactile sensor is physically flexible and it can be deformed three-dimensionally to any shape so that it can be placed on anywhere on the curved surface. In the future, the developed sensor is applied to a dexterous robotic hand...$\textbullet$ Tactile sensing, PVDF, Robot hand

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.05a
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• pp.190-194
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• 2002

Human uses sight, tactile sense to evaluate Total Hand Value(FUUAI) of textile fabrics. Tactile sense is important factor which decided the Total Hand Value of a textile fabric. When human feels the FUUAI, physical and physiological phenomena are occurred in finger. We first found out physical variable that is happened in fingertip when human is feeling the FUUAI. Such physical variable means characteristic of action tactual motion of finger such as moving range, tactile time, moved distance, speed of finger and applied force by finger. We study the relationship between action tactual motion and the ability in which the human distinguishes the textile fabric. As a result, we could know the characteristics of the tactual motion of fingertip to get high distinguishable ability. The characteristics were different in men and women respectively. In the case of man, touched time and moving range influenced to distinguish, and moving range, and the moving speed of finger influenced, in woman's case.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.1272-1274
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• 1996

This paper presents the development of tactile sensor systems for robot hand which are truly usable, robust, reliable and cheap system. The sensor incorporates multiple sensing subsystems for detecting distributed contact forces and surface characteristics. The fabrication and experimental evaluation of the tactile system and its electric interfaces are described. The results indicate that the system provides reasonable performances for practical applications requiring manipulation with tactile feedback.

• Journal of the Korean Society of Physical Medicine
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• v.4 no.3
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• pp.201-207
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• 2009

Purpose：The purpose of this study was to investigate the effect of $\alpha$-wave music and art appreciation on hand function in stroke with hemiplegia. Methods：A total of 32 stroke with hemiplegia participated in this study experimental group(16 subjects) received $\alpha$-wave music and art appreciation with general neurologic therapy. Control group(16 subjects) received general neurologic therapy. All subjects were assessed for hand function(manual dexterity, power grip, pinch grip, two point discrimination(parm, finger), tactile sense(parm, finger) using a purdue pegboard, dynamometer, pinch gauge, two-point anethesiometer and semmes-weinstein monofilament wire. The data were analyzed using paired and independent t-test. Results：The results were as follows : 1. In the experimental group, manual dexterity were significantly increased between pre and post intervention(p<.05). 2. In the experimental group, tactile sesne in finger were sifnificantly increased between pre and post intervention(p<.05). Conclusion：The results of this study shows that $\alpha$-wave music and art appreciation affect the hand function of hemiplegic side with regard to manual dexterity and tactile sense.

• Journal of the Korean Society of Physical Medicine
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• v.7 no.4
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• pp.481-491
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• 2012

PURPOSE: This study find out the effect of improved two point discrimination (TPD), hand function and activities of daily living (ADL) performance through tactile stimulus of upper limb (U/L) in impaired characteristics of stroke METHODS: We selected 26 stroke patients in BMH who has problems with neglect, sensory and motor deficits. Patients were divided into 3 group with neglect group (NG), sensorimotor deficits group (SMG) and motor deficit group (MG). To compare each group we used assessment tools such as two point discrimination on affected side (TPDas) and unaffected side (TPDus), Manual functional test on affected side (MFTas) and unaffected side (MFTus) and Korean version modified barthel index (K-MBI). RESULTS: 1) In the NG, tactile stimulus on U/L was statistically important for TPDas (forearm, index finger tip) also SMG and MDG was statistically important for TPDas. 2) In the NG, SMG, there was statistically important for MFTas, MFTus and in the MG. K-MBI also was statistically importance. Among three group, there was an statistically important difference for TPTus (forearm, thenar, hypothenar), MFTas and MFTus. We analyzed the relationship among TPD, MFT and K-MBI and There was negative relationship between TPD, MFT and There was positive relationship between TPD and K-MBI CONCLUSION: In impaired characteristics of stroke patients, tactile stimulus on U/L influenced on two point discrimination, hand function and ADL's. And we also found relationship among somatosensory, hand function, and ADL performance.