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Ulnar Nerve Compression at Guyon's Canal by an Arteriovenous Malformation

  • Kim, Sung-Soo;Kim, Jae-Hoon;Kang, Hee-In;Lee, Seung-Jin
    • Journal of Korean Neurosurgical Society
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    • v.45 no.1
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    • pp.57-59
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    • 2009
  • Guyon's canal at the wrist is not the common site of ulnar nerve compression. Ganglion, lipoma, anomalous tendon and muscles, trauma related to an occupation, arthritis, and carpal bone fracture can cause ulnar nerve compression at the wrist. However, ulnar nerve compression at Guyon's canal by vascular lesion is rare. Ulnar artery aneurysm, tortous ulnar artery, hemangioma, and thrombosis have been reported in the literature as vascular lesions. The authors experienced a case of ulnar nerve compression at Guyon's canal by an arteriovenous malformation (AVM) and the patient's symptom was improved after surgical resection. We can not easily predict vascular lesion as a cause of ulnar nerve compression at Guyon's canal. However, if there is not obvious etiology, we should consider vascular lesion as another possible etiology.

Robot Arm Control using Optimized Pinch Grasp Posture Based on Object Shape (물체형상 기반 로봇 팔 제어)

  • Orlando, M. Felix;Oh, Yong-Hwan
    • Proceedings of the KIEE Conference
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    • 2006.07d
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    • pp.1929-1930
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    • 2006
  • Human like robot arm posture for grasping by considering the shape of the target object is quite a challenge in the field of robotics. In this paper, an optimized grasp posture with respect to the shape of the object considering the wrist joint angle and elbow elevation angle, in order to verify that the grasp posture is human like has been proposed. Given a target object, the candidates for grasp are computed by the method described in this paper. For each candidate, the closed loop inverse kinematics has been solved for the corresponding hand position and orientation. From the obtained joint angles through inverse kinematics, the elbow elevation angle has been computed and compared with the elbow elevation angle obtained through human movement data by the characteristic equation. After considering all the candidates, the hand position and orientation with minimum wrist joint and difference in elbow elevation angles has been utilized as the optimized grasp posture. Simulation results are presented.

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Ultrasound Diagnosis of Double Crush Syndrome of the Ulnar Nerve by the Anconeus Epitrochlearis and a Ganglion

  • Lee, Sang-Uk;Kim, Min-Wook;Kim, Jae Min
    • Journal of Korean Neurosurgical Society
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    • v.59 no.1
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    • pp.75-77
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    • 2016
  • Double compression of the ulnar nerve, including Guyon's canal syndrome associated with cubital tunnel syndrome caused by the anconeus epitrochlearis muscle, is a very rare condition. We present a case of double crush syndrome of the ulnar nerve at the wrist and elbow in a 55-year-old man, as well as a brief review of the literature. Although electrodiagnostic findings were consistent with an ulnar nerve lesion only at the elbow, ultrasonography revealed a ganglion compressing the ulnar nerve at the hypothenar area and the anconeus epitrochlearis muscle lying in the cubital tunnel. Careful physical examination and ultrasound assessment of the elbow and wrist confirmed the clinical diagnosis prior to surgery.

Force control of the five-link robot using wrist force sensor (손목힘 센서를 이용한 5축 로봇의 힘제어)

  • 허영태;이장명
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.552-555
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    • 1996
  • In this paper, we present a force control of a five-axes robot, using an impedance model. Tasks such as assembly, grinding, and deburring, which involve extensive contact with the environment, are better handled by controlling the forces of interaction between the manipulator and the environment. The five-link articulated robot is equipped with a wrist force sensor which consists of an array of strain gauges and can delineate the three components of the vector force along the three axes of the sensor coordinate frame, and the three components of the torque about these axes. For the precise control of the contact force, impedance models of a robot and the environment are defined. Experimental results are shown.

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The Output Analysis of Wrist Force/ Torque Sensor for SCARA Type Robots (SCARA형 로보트를 위한 손목 힘/토오크 센서의 출력 해석)

  • 고명삼;하인중;이범희;고낙용
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.37 no.8
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    • pp.570-578
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    • 1988
  • In order for a robot to carry out a precise assembly task with compliant motion, a force/torque sensor is needed. The output of the cross-bar structured force / torque sensor which is used in a peg-in-hole insertion task and attached to a SCARA type robot, is analzed. First, the relationship between the sensor outputs and the force / torque components obtained by the outputs is investigated. Second, in a peg-in-hole insertion task, the sensor outputs changing with the contact position of the peg and the hole, are analyzed. Also, the relative position of the peg and the hole is obtained from the sensor outputs. The peg-in-hole insertion task is successfully executed, using a SCARA type robot with a wrist force / torque sensor manufactured in our laboratory and the compliance algorithm from the results of this paper.

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Four degrees of freedom robot gripper for assembly robots (SCARA robot를 위한 4자유도 end-effector 개발)

  • ;Besant, C.S.
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.511-516
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    • 1991
  • A new end-effector has been devised and the problems resulted from using it with SCARA robots are discussed. The end effector has two modules: one composed of two ultrasonic motors and two encoders for controlling each finger, and the other module composed of two ultrasonic motors and two encoders for controlling the wrist. The wrist module adds two degrees of freedom to the SCARA type robot, which generally has four degrees of freedom. With independent finger actuation and touch sensors, the gripper under computer control can feedback information about part size and part presence. Ultrasonic motors with high torque and slow motion characteristics are used. The principle of ultrasonic motors is explained and the servo characteristics of ultrasonic motors are studied. They are controlled by the general motion controller (Hewlett Packard HCTL-1000) which is linked to an IBM-PC AT.

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A Comparative Study on Determinant Methods for Body Frame Size of the Elderly (노인의 골격크기 결정방법에 관한 비교조사연구)

  • 한경희
    • Korean Journal of Rural Living Science
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    • v.5 no.2
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    • pp.117-123
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    • 1994
  • The purpose of this study was to establish the range of the body frame size determination for elderly subjects. Anthropometric data were collected from over 60 years old 229 elderly peoples. Three methods for determining frame size were to measure elbow breadth, ankle breadth, and height to wrist circumference ratio. Among the three variables, ankle breadth exhibited the lowest correlation with skinfold thickness and changed little with age. A pairwise comparision among three methods for determining frame size showed that the highest incidence of overall agreement was achieved when the ankle breadth and elbow breadth were compared. This analysis supported that ankle breadth can be used as an indicator of frame size. Small, medium and large categories of ankle breadth were presented depending on whether the measurements were below the 15th, between the 15th and 85th, and above the 85th percentile for ankle breadth.

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DULEX, A Wearable Hand Rehabilitation Device for Stroke Survivals (뇌졸중 환자를 위한 착용형 손 재활훈련기기, DULEX)

  • Kim, Young-Min;Moon, In-Hyuk
    • 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.

One more many more criteria for a design of ergonomic keyboard-slope angle (Keyboard Frame의 평면경사각과 측면경사각 및 Keypad 평면회전각의 변화가 Typing 수행도에 미치는 영향에 관한 연구)

  • 이면우;전영호;장성록;이도준;최재호;김대철;지철규;박현규
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1990.04a
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    • pp.151-162
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    • 1990
  • Occupational disease among typists such as Carpal Tunnel Syndrome(CTS) and tendonitis has increased along with rapid expansion of office automation. During typing, the posture can be defined as forearm pronation, ulnar abduction, wrist extension and finger flexion. The CTS results from awkward posture between forearm-wrist-hand and the keyboard arrangement. Therefore, ergonomic principles should be emphasized in keyboard design. The objective of the study is to improve keyboard design by analyzing anatomical posture of forearm and hand during typing. An experimental study was performed to investigate relationships between a keyboard and typing performance. Results showed that typing performance is dependent to angles and slopes of a keyboard. Statistical analysis indicated that the suggested ergonomic keyboard improved typing speed significantly(17%).

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A Suggestion of Sizing System for Clean Room Wear (무진복의 치수체계에 대한 연구)

  • 이경화
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.7
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    • pp.1044-1055
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    • 2000
  • The purpose of this study is to suggest sizing chart for a clean room wear. 3 control dimensions(Stature, Bust girth, B.N.P.∼Wrist point length) were chosen as 3 axes of clean room wear size chart. A loss function was used to determined intervals of stature, Bust girth and B.N.P.∼Wrist point length of size chart, because the loss function introduces the concept of frequency to size chart for better customer's size satisfaction. From the size table whose intervals had been determined by a loss function. The 4 sizes individually were suggested for clean room wear size chart by sex. The 3 sizes individually were suggested for clean room head cover size chart by sex too. The suggested size chart would be considered more feasible than present size chart. Also they are suggested supply reference measurement chart relevant to clean room wear manufacturing for 13 most frequent sizes.

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