무게균형진자 탑재형 4족 로봇의 개발

최기훈(Gi-Hun Choi),김영탁(Young- Tark Kim) 대한기계학회 2002 대한기계학회 춘추학술대회 Vol.2002 No.5

Quadruped walking robot requires dynamic control to keep its stability in high speed walking. To keep its walking stability by control of only legs' joint angle lowers energy efficiency. In this study, a quadruped walking robot with weight balancing oscillator will be developed for promotion of energy efficiency. The oscillator is designed to rolls from side to side when the robot dynamically move.

스키 손상에 의한 외상성 삼첨판 역류 1례

최기훈 ( Gi Hun Choi ),서정열 ( Jeong Yeol Seo ),안무업 ( Moo Eob Ahn ),안희철 ( Hee Cheol Ahn ),김성은 ( Sung Eun Kim ),천승환 ( Seung Hwan Cheun ),이승용 ( Seung Yong Lee ),최광민 ( Kwang Min Choi ),김형수 ( Hyung Soo Kim ),정 대한외상학회 2006 大韓外傷學會誌 Vol.19 No.2

Tricuspid regurgitation after blunt chest trauma is rarely seen in the emergency department. A 19-year-old patient visited our emergency department with chest discomfort after collision with his brother while skiing. Recently, Skiing as a winter sports has become popular with the Korean people, so there is an increasing tendency for patients with diverse traumas associated with ski accidents to visit the emergency department. From simple abrasions or contusions to deadly injuries with unstable vital signs, we are seeing many kind of injuries in the emergency department. We present the case report of a patient with tricuspid regurgitation after a blunt chest trauma during the skiing. (J Korean Soc Traumatol 2006;19:188-191)

정량적인 Bi-Digital O-링 테스트

최기훈(Gi-Hun Choi),김영탁(Young-Tark Kim),여인철(In-Chol Yeo),김중(Joong Kim) 한국정밀공학회 1999 한국정밀공학회 학술발표대회 논문집 Vol.1999 No.11월

히말라야 석청으로 인한 중독

최기훈 ( Gi Hun Choi ),유기철 ( Ki Cheol You ),왕순주 ( Soon Joo Wang ),박태진 ( Tae Jin Park ) 대한임상독성학회 2012 대한임상독성학회지 Vol.10 No.1

Honey is produced by bees from nectar collected from nearby flowers. Sometimes, honey produced from the Rhododendron species is contaminated by Grayanotoxin (GTX) in Nepal and other countries. There have been reports of GTX intoxication, also known as ‘mad honey disease’, from honey produced in countries other than Korea. The importation of wild honey has been prohibited by the Korean Food and Drug Administration since 2005, yet it is still distributed within Korea by the occasional tourist. We report a case of GTX intoxication from contaminated honey which included the symptoms of nausea, vomiting, general weakness, dizziness, blurred vision, hypotension and sinus bradycardia. By means of infusion with normal saline and atropine sulfate, the patient’s condition fully recovered within 8 hours of hospital admission, and she was discharged without any complications.

균형추를 장착한 4족 로봇의 보행 안정성에 관한 연구

최기훈(Gi Hun Choi),유재명(Jae Myung Yoo),김영탁(Young Tark Kim) Korean Society for Precision Engineering 2005 한국정밀공학회지 Vol.22 No.6

There are many types of walking robots in the world. For dynamic walking of the robots it is necessary to keep its dynamic stability. The dynamic stability is influenced by the position of ZMP (zero moment point). In this paper we study the control of the ZMP position of walking robot. For experiment we developed a quadruped robot and analyzed the dynamic stability of the robot. Developed robot has 2 joints at each leg and WBO (weight balancing oscillator) on the body of the robot. The WBO is designed to move linearly from side to side when the robot walks dynamically. Walking test was performed to verify the validity of the proposed methods. Especially we showed that the dynamic stability of the robot can be improved without sacrifice of the walking speed by control the WBO.

마이크로폰 배열로 발생되는 입력 시간차를 이용한 음원의 방향 추정 장치에 관한 연구

윤준호(Jun Ho Yoon),최기훈(Gi Hun Choi),유재명(Jae Myung Yoo) Korean Society for Precision Engineering 2004 한국정밀공학회지 Vol.21 No.5

Human uses level difference and time difference to get space information. Therefore this paper shows that method to presume direction of sound source by time difference and to mark presumed position. The position means direction from geometrical center of sensors to the sound source. To get the time difference of microphones input level, we will be explained about arrangement of microphones which used for the sensor to take the sound signal. It is included distance among the 3 microphones and distance between microphones and sound source. Secondly, input signals are transmitted to CPU througth digital process. CPU is used to DSP(Digital Signal Processor) for manage the signal by real time. Finally, the position of sound source is perceived by an explained alogrithm in this paper.

O-링 테스터의 측정팁 구조개선

최기훈,여인철,김영탁 중앙대학교 미래신기술연구소 2001 미래신기술연구소 논문집 Vol.10 No.2

It is usual that the medical examination of human body need special knowledge and equipments. Thus we have to spend time and energy on going to special place such as hospital where doctors and equipment are. Which often cause missing a good chance of medical treatment as well as giving us inconvenience. However may simple and convenient equipments were developed for checking our health conditions recently. O-ring test is accepted as one of useful methods to examine our health conditions. Also the test is recognized as a useful means to judge if some medical substances or foods are beneficial or harmful to our health without any special equipment and medical knowledge. An automatic O-ring test machine has been developed[11]. However the tester have a problem that the pattern of applied force to the O-ring is different from that of manual case. In this study, the reaction force tip is modified and the validity of the tip is verified through experiments.

O-링 테스트의 정량화에 관한 연구

최기훈,여인철,김영탁 중앙대학교 생산공학연구소 2000 생산공학연구소 논문집 Vol.9 No.2

신체의 건강진단을 위해서는 값비싼 장치의 전문지식이 요구된다. 따라서 장비를 갖춘 병원과 같은 특정 장소에서 전문지식을 가진 의사를 만나기 위해 시간과 노력을 들여 이동해야만 한다. 그러나 최근에는 간단하게 진단을 할 수 있는 장치가 개발되어 있다. 0-링 테스트는 특별한 장치가 없이도 간단한 지식으로 건강진단 및 약물이나 음식물의 이해 여부를 판단할 수 있는 유효한 진단방법으로 인식되고 있다. 하지만 이 테스트 법은 검사자의 경험과 주관에 의존하므로 결과에 대한 신뢰성과 객관성이 문제시되고 있다. 본 연구에서는 0-링 테스트 시스템을 고안하여 테스트결과가 객관적이고 정량적으로 나타나도록 하여, 손쉽게 결과를 판단 할 수 있게 하고자 한다. It is usual that the medical examination of human body need special knowledge and equipments. Thus we have to spend time and energy on going to special place such as hospital where doctors and equipments are. Which often cause missing a good chance of medical treatment as well as giving us inconvenience. However many simple and convenient equipments were developed for checking our health conditions recently. 0-ring test is accepted as one of useful methods to examine our health conditions. Also the test is recognized as a useful means to judge, without any special equipment and medical knowledge, if some medical substances or foods are beneficial or harmful to our health. However, the judgement may be incorrect because it depend on doctor's subjective point of view. In this study, we developed an automatic 0-ring test machine which enable us to check our health conditions objectively and quantitatively. The validity of the idea to develope the machine was proved by experiments.

소형 4족 로봇의 정적 걸음새에 관한 연구

김태형,최기훈,김영탁 중앙대학교 미래신기술연구소 2001 미래신기술연구소 논문집 Vol.10 No.1

보행 로봇은 시스템이 갖는 많은 자유도의 효율적 제어의 어려움으로 인해 많은 장점 및 연구에도 불구하고 실용화가 미비하였다. 따라서 최근에는 단순화된 메커니즘 설계에 의한 보행 로봇이 개발되고 있으며, 이러한 형태의 로봇에 대해 정적 및 동적 안정성을 유지하면서도 이동성 및 속도를 향상시키고자 하는 연구가 진행되고 있다. 본 논문에서는 각 다리의 자유도 수를 줄인 보다 단순화된 메커니즘 설계에 의해 4족 보행 로봇 FRAMIX-T를 개발하였다. 그리고, 이러한 구조의 로봇에 적합한 보행 알고리즘 및 안정성 해석법을 제시하였다. 기존의 안정성 해석법에 비해 이러한 방법은 안정 경계선 및 정적 안정 영역을 이용하여 복잡한 기구학적 계산과정 없이 로봇의 안정성을 판별할 수 있으며, 또한 동시에 안정된 보행을 위한 연속적인 다리의 이동 순서 및 각 발의 허용 착지 범위를 결정할 수 있는 장점이 있다. 본 논문에서 제시한 로봇의 구조적 단순화와 새로운 안정성 해석 및 걸음새 계획법은 여러 형태의 소형 4족 보행 로봇에 적용될 수 있을 것이다. Recently, the walking robots by much simplified mechanism design that reduce the number of leg and the degree of freedom were developed, and researches for the robot of these form that intend to improve mobility and speed ass keeping static and dynamic stability are going. In this paper, the quadruped robot, FRAMIX-T was developed by much simplified mechamism design that reduce the degree of freedom of leg. The walking algorithm and the stability analysis method appropriate for it have been discussed . This method not only avoids finding the solutions of the complicated kinematics, but also simultaneously shows the robot stability and the stable area of foot position. The simplified mechanism, new stability analysis and gait generation method can be applied to various quadruped robot.