• 한국공작기계학회논문집
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• 제14권4호
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• pp.81-88
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• 2005

This paper attempts to derive the dynamic model of handling tasks in finger robot which grasps stable and manipulates a rigid object with some dexterity. Firstly, a set of differential equation describing dynamics of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. Secondly, the roblems of controlling both the forces of pressing object and the rotation angle of the object under the geometric constraints are discussed. The effect of geometric constraints of area-contacts between the link's end-effector and the object is analyzed and the model based on the differential-algebraic equations is presented. In this paper, the control method for dynamic stable grasping and enhancing dexterity in manipulating things is proposed. It is illustrated by computer simulation and the experiment that the control system gives the performance improvement in the dynamic stable grasping and nimble manipulating of the dual fingers robot with soft tips.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 추계학술대회 논문집
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• pp.219-224
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• 2002

This paper aims to derive a mathematical model of the dynamics of handling tasks in robot finger which stable grasping and manipulates a rigid object with some dexterity. Firstly, a set of differential equation describing dynamics of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. Secondly, problems of controlling both the internal force and the rotation angle of the grasped object under the constraints of area-contacts of tight area-contacts are discussed. The effect of geometric constraints of area-contacts on motion of the overall system is analyzed and a method of computer simulation for overall system of differential-algebraic equations is presented. Thirdly, simulation results are shown and the effects of geometric constraints of area-contact is discussed. Finally, it is shown that even in the simplest case of dual single D.O.F manipulators there exists a sensory feedback from sensing data of the rotational angle of the object to command inputs to joint actuators and this feedback connection from sensing to action eventually realizes secure grasping of the object, provided that the object is of rectangular shape and motion is confined to a horizontal plane.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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• pp.568-576
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• 1998

In this thesis discuss with a flexible robotic finger design and controller which is used for the micro flexible robotic finger. So, miniaturization, precision, controller for the control of grasping force and actuator were needed. And, even if we develop a new actuator and controller, in order to use on real system, we must considerate of a many side problem. In a force control of micro flexible finger for grasping an object, the fingertip's vibration was more important task of accuracy control. And, controller were adopt the PD/PI mixed type fuzzy controller. The controller were consist of two part, one is a PD type fuzzy controller for increase the rising time response, the other is a PI type fuzzy controller for decrease of steady-state error. Especially, in a PD type fuzzy controller, we used only seven rules. And, for a PI controller, we adopt a reset factor for the control of input values. so, we have overcome the exceed of controller's input range. For the estimate of ontroller's utility and usefulness, we have experiment and computer simulation of three cases. First, we consider of unit force grasping control for a task object, which is 0.03N. Second, bounding grasping force control which is add to a sinusoidal force on the unit force. At this cases the task force is (0.03+0.01 sin wt N). And consider of following of rectangular forces.

• 센서학회지
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• 제19권3호
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• pp.238-245
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• 2010

Stroke patients can't use their hands because of the paralysis of their fingers. Their fingers are recovered by rehabilitating training, and the rehabilitating extent can be judged by grasping a spherical object. At present, the object used in hospital is only a spherical object, and can't measure the force of fingers. Therefore, doctors judge the rehabilitating extent by touching and watching at their fingers. So, the spherical object measuring system which can measure the force of their fingers should be developed. In this paper, the finger-force measuring system with a three-axis force sensor which can measure the spherical-object grasping force is developed. The three-axis force sensor is designed and fabricated, and the force measuring device is designed and manufactured using DSP(digital signal processing). Also, the grasping force test of men is performed using the developed finger-force measuring system, it was confirmed that the average force of men was about 120 N.

• 대한물리의학회지
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• 제4권4호
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• pp.209-214
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• 2009

Purpose：The purpose of this study are analysis characteristic of grasping power with each different elbow flexion degree and grasping power with each different elbow each different hand position and announcement. Methods：Measuring about 10cm wide open position with both feet for each elbow in the line positions of the $0^{\circ}$, $45^{\circ}$, $90^{\circ}$, $135^{\circ}$, and forearm position of supination, mid position, pronation is of the order. Results：The averge position of maximal grip strength was $0^{\circ}$ of elbow flexion with mid position in male and $90^{\circ}$ of elbow flexion with mid position in female. Grip strength in change of wrist position according to elbow flexion was significant difference(P<0.05). Grip strength in change of wrist position according to elbow flexion by sex was significant difference(P<0.05) Conclusion：When the elbow has flexion with $0^{\circ}$, $45^{\circ}$, $90^{\circ}$, $135^{\circ}$ then grasping power has a intimate relation with forearm position. Grasping power with forearm supination, pronation and mid position also has a intimate relation with elbow flexion.

• 한국전문물리치료학회지
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• 제15권3호
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• pp.44-52
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• 2008

The purpose of this study was to investigate the effects of different objects and target location of dominant hand on the non-dominant hand movement kinematics in a bimanual reaching task. Fifteen right-handed volunteers were asked to reach from same starting point to the different target point of right and left hand with grasping the objects of different size. Independent variables were 1) three different object types (small mug cup, name pen, and PET bottle), and 2) three different target locations (shorter distance, same distance, and longer distance than the non-dominant hand) of the dominant hand. Dependent variables were movement time (MT), movement distance (MD), movement mean velocity ($MV_{mean}$), and movement peak velocity ($MV_{peak}$) of the non-dominant hand. Repeated measures two-way analysis of variance (ANOVA) was used to test for differences in the non-dominant hand movement kinematics during bimanual reaching. The results of this study were as follows: 1) MT of the non-dominant hand was increased significantly when traveling with grasping the mug cup and reaching the far target location, and was decreased significantly when traveling with grasping the PET bottle and reaching the near target location of the dominant hand. 2) MD of the non-dominant hand was significantly increased during reaching the far target location, and significantly decreased during reaching the near target location with dominant hand. 3) $MV_{mean}$ of the non-dominant hand was increased significantly when traveling with grasping the PET bottle, and was decreased significantly when traveling with grasping the mug cup of the dominant hand. Therefore, it can be concluded that the changes of the ipsilateral hand movement have influence on coupling of the contralateral hand movement in bimanual reaching.

• The Journal of Korean Physical Therapy
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• 제28권1호
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• pp.52-58
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• 2016

Purpose: This study intended to mediate shoulder exercise using grasping and investigate examine how its effects on affects activities of the shoulder surrounding muscles of the shoulder and thickness of shoulder muscle to suggest effective exercise for patients with rotator cuff repair to return to daily life. Methods: This study has been done targeteding male patients more than 6 weeks after having En-masse Suture Bridge Technique as rotator cuff repair of the right shoulder, aged 40 to 55 in a medical institution located in Jeollanam-do. Experimental group I (n=15) was selected for a conducting common exercise therapy program and Experimental group II (n=15) was selected for an conducting exercise therapy program using grasping. %RVC was measured by surface electromyography and muscle thickness was measured by ultrasound before mediation to for analysisze of before and after results within group and between groups. Results: In comparison of change of %RVC, Tthere were meaningful differences in only posterior deltoid and infraspinatus in comparing a change of %RVC within experimental group I (p<0.001),. and Tthere were meaningful differences in both supraspinatus and infraspinatus in muscle thickness within experimental group I (p<0.001). In comparison of change of %RVC, Tthere were meaningful differences in anterior deltoid, posterior deltoid and infraspinatus in comparing a change of %RVC within experimental group II (p<0.05)(p<0.01) (p<0.001), and there were meaningful differences in both supraspinatus and infraspinatus in muscle thickness within experimental group II (p<0.001). In comparison of change of %RVC between groups, Tthere was a meaningful difference in only posterior deltoid in comparing a change of %RVC between groups (p<0.001). Conclusion: We found that exercise therapy using grasping has a positive effect on shoulder stability muscles such as supraspinatus muscle and infraspinatus muscle and activity of deltoid muscle.

• 근관절건강학회지
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• 제15권1호
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• pp.62-72
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• 2008

Purpose: There has been a need to integrating the self-help program for arthritis with the Tai Chi for arthritis(SHTCA). The purpose of this study was to develop and to examine the effect of SHTCA for arthritis applying the nine movement Tai Chi. Method: This study was designed the pre-post test, quasi-experimental design. A total 47 participants were recruited in W-city in Korea, an experimental group(26) and a control group(21) at pre-test, but after the eight weeks the composition of the groups were changed to 22 experimental group and 15 control group. The experimental group participated in the SHTCA once a week for eight weeks. SHTCA program consisted of understanding of the arthritis, contracting of the promise, exercise for muscle strength and joint flexibility and the nine movements of Tai Chi exercise. The measures used to examine the effect of the SHTCA were shoulder flexibility, back flexibility, grasping power, balance, abdominal obesity rates, perception of health status, and EQ-5D standardized five dimensions, mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Results: At The completion of the eight weeks of SHTCA applying the nine movement Tai Chi, the experimental group reported a significance in a number of variables compared to those of the control group: the right shoulder flexibility(p=.018), left shoulder flexibility(p=.031), right grasping power(p=.014), left grasping power(p=.024), the perception of health status(p=.005) and abdominal obesity rates(p=.027). Conclusion: This SHTCA applying the nine movement Tai Chi would be helpful on right shoulder flexibility, left shoulder flexibility, right grasping power, left grasping power, abdominal obesity rates and the perception of health status for arthritis patients.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.712-715
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• 1997

In image jacobian based visual servoing, generally, inverse jacobian should be calculated by complicated coordinate transformations. These are required excessive computation and the singularity of the image jacobian should be considered. This paper presents a visual servoing to control the pose of the robotic manipulator for tracking and grasping 3-D moving object whose pose and motion parameters are unknown. Because the object is in motion tracking and grasping must be done on-line and the controller must have continuous learning ability. In order to estimate parameters of a moving object we use the kalman filter. And for tracking and grasping a moving object we use a fuzzy inference based reinforcement learning algorithm of dynamic recurrent neural networks. Computer simulation results are presented to demonstrate the performance of this visual servoing

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2665-2669
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• 2003

A wearable device to assist fingering function for disabled is developed in this study. This is the second paper to report the progress in development of this assisting device. The device is developed for a patient who suffers from cervical spinal cord injury. In the first paper, it was reported that the patient could successfully pick up several types of objects with his paralyzed fingers by using this device. As a next step, the maneuverability of the device under grasping operation is discussed in this paper. Maneuverability of the system is experimentally evaluated. The dexterity in controlling finger force is compared between the cases that non-disabled examinees operate their finger with inherent abilities and that a disabled examinee operates his finger by using the assisting device.