• Journal of the Korean Institute of Intelligent Systems
• /
• v.22 no.5
• /
• pp.533-539
• /
• 2012

The purpose of this study is to estimate a validity of control signal through a design of Exoskeleton Robot Arm's capable of intelligent recognition as a human arm's motion by using realtime processed data of generated EMG signals. By an intelligent algorithm, the EMG output value of human biceps and triceps muscles contraction can be recognized and used for the control over exoskeleton arm corresponding to human's recognition and judgement. The EMG sensing data of muscles contraction and relaxation are used as the input signal from human's body to operate the Exoskeleton Robot Arm thus copying human arm motion. An intelligent control of Exoskeleton Robot Arm is to design the analog control circuit which processes the input data, and then to manufacture an integrated control board. And then abstracted signal is passed by DSP signal processing, Fuzzy logic algorithm is designed for a accurate prediction of weight or load through the intelligent algorithm, and design an Exoskeleton Robot Arm to express a human's intention.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.04a
• /
• pp.883-885
• /
• 2004

음함수 곡면은 부정형 물체의 모델링 성능이 탁월하여 다양한 골격요소가 사용된다. 골격요소의 모양이 다양할 수록 모델링 성능이 향상되는 반면 렌더링은 상대적으로 어려워진다. 따라서 본 논문에서는 다양한 골격요소를 사용하는 음함수 곡면을 interval method로 렌더링 하는 방법을 소개한다. 또한 정(point) 외에 복잡한 도형을 골격요소로써 사용할 때, interval method를 적용하는 경우 직면하게 되는 문제 해결 방법을 제안한다.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.8 no.3
• /
• pp.177-185
• /
• 2014

In this study, the exoskeleton orthosis for the assistance of dorsiflexion torque in ankle joint to prevent foot-drop was developed. It was consist of three part; 1) the power part using artificial pneumatic actuator, 2) wearing part of ankle and knee joints to fix the orthosis, and 3) control part to detect the gait phase using physiological signal. The dorsiflexion torque was generated by the artificial pneumatic actuator connected with wearing part between ankle and knee joint. The accurate timing to assist dorsiflexion torque is made up of physiological signal in foot sole part that detect the gait phase, that is, stance and swing phase in each foot. We conduct the experiment to investigate the effect of exoskeleton orthosis to the 7 elderly people and 10 healthy people. The result showed that the muscular activities in tibialis anterior muscle were reduced because of the assistance of dorsiflexion torque in ankle joint using the exoskeleton orthosis.

• Journal of the Korean Society of Radiology
• /
• v.82 no.1
• /
• pp.212-218
• /
• 2021

Ewing sarcomas constitute a group of small, round, blue cell tumors of the bone and soft tissue. Extraskeletal Ewing sarcoma (EES) is a rare malignant neoplasm that arises from soft tissues, and it usually affects children and young adults. EES of the thoracopulmonary region commonly presents with a palpable mass or pain. Although rarely reported, EES affecting the anterior chest wall may present as a breast mass. We report a case of EES arising from the chest wall and manifesting as a palpable breast mass in a 22-year-old woman. The large mass was initially misdiagnosed as a breast origin mass on ultrasonography, but subsequent CT and MRI showed that the mass originated from the chest wall. Radiologists should be aware of the imaging findings of EES, and they should understand that chest wall lesions may be clinically confused as breast lesions.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2012.05a
• /
• pp.1309-1310
• /
• 2012

• Journal of Aerospace System Engineering
• /
• v.11 no.6
• /
• pp.26-33
• /
• 2017

We propose a variable frame structure connected with telescopic mast-shaped shaft for a robot displaying outstanding ability to cross obstacles, and for effective traction control. The wireless control system was built to extend and contract a deployable mechanism, which is shaped into a hoberman sphere assembled with frame structures. In order to develop important parameters for efficient locomotion, we derived an Euler-Lagrange equation for the spherical robot. According to the equation, the DC motor was selected. A prototype mechanism was tested and a Finite-Element Analysis (FEA) was conducted in parallel. Using these data, we constructed a deployable spherical robot with structural stability. The deployable robot moved at a speed of 0.85 m/s from 520 mm to 650 mm.

• Journal of the Korean Society for Precision Engineering
• /
• v.32 no.12
• /
• pp.1065-1072
• /
• 2015

This paper is about the development of an insole sensor system that can determine the model of an exoskeleton robot for lower limb that is a multi-degree of freedom system. First, the study analyzed the kinematic model of an exoskeleton robot for the lower limb that changes according to the gait phase detection of a human. Based on the ground reaction force (GRF), which is generated when walking, to proceed with insole sensor development, the sensing type, location, and the number of sensors were selected. The center of pressure (COP) of the human foot was understood first, prior to the development of algorithm. Using the COP, an algorithm was developed that is capable of detecting the gait phase with small number of sensors. An experiment at 3 km/h speed was conducted on the developed sensor system to evaluate the developed insole sensor system and the gait phase detection algorithm.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.06a
• /
• pp.35-36
• /
• 2008

• Journal of Life Science
• /
• v.19 no.10
• /
• pp.1484-1488
• /
• 2009

Familial hypokalemic periodic paralysis (HOKPP) is an autosomal dominant muscle disorder characterized by episodic attacks of muscle weakness with concomitant hypokalemia. Mutations in either a calcium channel gene (CACNA1S) or a sodium channel gene (SCN4A) have been shown to be responsible for this disease. The combination of sarcolemmal depolarization and hypokalemia has been attributed to abnormalities of the potassium conductance governing the resting membrane potential. To understand the pathophysiology of this disorder, we examined both mRNA and protein levels of delayed rectifier potassium channel genes, KCNQ3 and KCNQ5, in skeletal muscle fibers biopsied from patients with HOKOur results showed an increase in the cytoplasmic level of KCNQ3 protein in patients' cells exposed to 50 mM external concentration of potassium. However, mRNA levels of both channel genes did not show significant change in the same condition. Our results suggest that long term exposure of skeletal muscle cells in HOKPP patients to high extracellular potassium alters the KCNQ3 localization, which could possibly hinder the normal function of this channel protein. These findings may provide an important clue to understanding the molecular mechanism of familial hypokalemic periodic paralysis.

• Journal of the Korean Society for Precision Engineering
• /
• v.29 no.3
• /
• pp.346-353
• /
• 2012

The purpose of this study is to verify the energy efficiency of the integrated system combining human and a lower extremity exoskeleton robot when it is applied to the proposed gait pattern. Energy efficient gait pattern of the lower limb was proposed through leg function distribution during stance phase and the dynamic-manipulability ellipsoid (DME). To verify the feasibility and effect of the redefined gait trajectory, simulations and experiments were conducted under the conditions of walking on level ground and ascending and descending from a staircase. Experiments to calculate the metabolic cost of the human body with or without the assistance of the exoskeleton were conducted. The energy consumption of the lower extremity exoskeleton was assessed, with the aim of improving the efficiency of the integrated system.