반발식 동전기 휠을 이용한 비접촉 반송 시스템의 변수 설계

정광석(Jung, Kwang Suk) 한국산학기술학회 2016 한국산학기술학회논문지 Vol.17 No.3

도전성 평판에 부분적으로 걸쳐 회전하는 축형 동전기 휠을 구동원으로 이용하는 비접촉 반송 시스템을 제안한다.회전하는 동전기 휠에는 3축력이 발생되는데 이 중 중력방향 힘과 횡방향 힘은 자기안정성을 갖고 있으므로 공간상에서 반송 시스템의 동적 안정성을 확보하기 위해서는 길이 방향 힘만을 제어하는 것으로 충분하다. 동전기 휠은 원주 방향을 따라 주기적으로 반복되는 극성을 갖는 영구자석으로 구성되어있으므로 기본 극의 기하학적 형상이나 극수 등은 안정성 여유에 큰 영향을 미친다. 또한 휠과 전도판간의 중첩된 영역 역시 횡방향으로의 강성을 결정하는 주요 인자이므로 본 논문에서는 안정성을 성능 지표로 휠을 구성하는 주요 설계 변수에 대한 민감도 해석을 수행한다. 얻어진 설계 값을 이용하여 제작된 시스템으로 휠을 포함하는 이동 개체의 수동적인 안정성을 실험적으로 검증한다. We propose a novel contact-free transportation system in which an axial electrodynamic wheel is applied as an actuator. When the electrodynamic wheel is partially overlapped by a fixed conductive plate and rotates over it, three-axis magnetic forces are generated on the wheel. Among these forces, those in the gravitational direction and the lateral direction are inherently stable. Therefore, only the force in the longitudinal direction needs to be controlled to guarantee spatial stability of the wheel. The electrodynamic wheel consists of permanent magnets that are repeated and polarized periodically along the circumferential direction. The basic geometric configuration and the pole number of the wheel influence the stability margin of a transportation system, which would include several wheels. The overlap region between the wheel and the conductive plate is a dominant factor affecting the stiffness in the lateral direction. Therefore, sensitivity analysis for the major parameters of the wheel mechanism was performed using a finite element tool. The system was manufactured based on the obtained design values, and the passive stability of a moving object with the wheels was verified experimentally.

자기차륜을 이용한 전도성 평판 이송 시스템에서 평판 위치 제어를 위한 새로운 방법

정광석(Kwang Suk Jung) 한국생산제조학회 2013 한국생산제조학회지 Vol.22 No.6

참조패턴 기반의 2차원 변위 측정 방법론

정광석(Kwang Suk Jung),이상헌(Sang Heon Lee),박성준(Sung-Jun Park) 한국생산제조학회 2013 한국생산제조학회지 Vol.22 No.1

특급호텔 식음료업장별 이용객의 소비성향의 탐색적 연구

정광석(Jung, Kwang-Suk),안형찬(Ahn, Hyung-Chan) 한국외식산업경영학회 2007 외식산업경영연구 Vol.3 No.1

자기 폐회로를 갖는 축형 마그네틱 기어

정광석(Kwang Suk Jung) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.7

마그네틱 셔터 기어는 원주상에 마주하는 영구자석 레이어간의 자기장을 고조파 모듈레이터를 통해 동기화시켜 동력을 전달하는 장치이다. 이러한 장치는 기계식 감속기에 필적할만한 토크를 발생시키기 위해 과다한 희토류 영구자석이 이용되기 때문에 본 논문에서는 영구자석간의 자기 경로를 변화시켜 영구자석의 양을 기존 마그네틱 기어 대비 50% 수준으로 감소시킨 새로운 방식의 축형 마그네틱 기어를 제안한다. 제안한 시스템의 토크 크기는 공극 자기장의 고조파 분석과 유한 요소 해석을 통해 기존 시스템과 비교된다. 모듈레이터 두께와 개방비가 전달 토크의 크기에 영향을 미치는 주요 설계변수로 고려되어 민감도 해석이 수행되며 고속측과 저속측의 영구자석 극수에 의해 결정되는 기어비에 따른 코깅의 크기가 분석된다. 기계적인 접촉없이 커플링되어 동력을 전달하는 고속측과 저속측 사이의 동적 지배 모델이 유도된다. 2관성 공진계의 동특성을 갖는 유도된 모델을 기초로 하여 선형 제어기를 설계하여 고속측의 계단 입력 위치 제어를 수행하였다. A magnetic shutter gear is a device that transfers mechanical power by synchronizing the magnetic field between permanent magnet layers facing circumferentially through a harmonic modulator. However, magnetic gears uses many rare-earth permanent magnets to guarantee comparable torque density to that of mechanical reducer. Hence, we propose a novel axial magnetic gear with a dramatically reduced number of permanent magnets and a closed magnetic path. The torque of the system was compared to that of an existing shutter gear through a harmonic analysis of the air-gap magnetic field. The modulator thickness and open ratio were considered as the primary design parameters, and the cogging effect was analyzed for variation of the reduction ratio. A dynamic model between the high-speed side and low-speed side was derived, and position control was performed for a constructed hardware implementation.

마그네트 휠의 공극 자기장 차폐판 조절에 의한 도전성 평판의 비접촉 반송

정광석(Kwang Suk Jung),심기본(Kwang Suk Jung),이상헌(Sang Heon Lee) Korean Society for Precision Engineering 2010 한국정밀공학회지 Vol.27 No.7

비접촉 동력 전달을 위한 마그네트 기어 기반 감속기의 속도 제어에 관한 연구

정광석(Kwang Suk Jung) 한국산학기술학회 2016 한국산학기술학회논문지 Vol.17 No.7

마그네트 기어를 이용하면 기계적인 접촉없이 동력을 전달할 수 있다. 마그네트 기어 기반 감속 시스템에서 종동축은 구동축으로부터 분리되어있기 때문에 시스템은 제한된 공극 강성으로 부하 변화에 대응해야하는 2관성 공진 시스템이다. 종동축 즉, 저속측은 구동축 인가 토크만으로 제어되고 갑작스런 외란에 따라 일반적인 기계식 기어 시스템과 달리 과도한 진동이나 슬립이 발생할 수 있다. 따라서 저속측에 인가되는 부하 등의 외란은 실시간으로 측정되거나 추정되어야 한다. 본 논문에서는 고조파 조절기 일체형 마그네트 기어를 이용한 감속 시스템의 저속측 속도 제어를 위한 전상태 되먹임 제어기를 제안하고 이를 전산 모의 시험과 실험을 통해 검증하였다. 저속측 부하를 추정하기 위해 새로운 상태변수를 도입하여 관측기 를 설계하였으며 이를 기반으로 하는 전상태 제어기를 통한 외란에 대한 강건성은 2자유도 PI 속도 제어기와 비교하였다. 상대적으로 짧은 시간안에 극의 슬립이 보정되는 것을 확인하였으며 추정된 변수는 실제 측정 결과와 유사한 경향을 나타내 었다. 이러한 결과는 마그네트 기어 감속기의 서보 시스템으로의 응용 가능성을 담보해주는 결과인 것으로 판단된다. Using the magnet gear, it is possible to transmit power without mechanical contact. As the drive shaft in a magnet gear-based speed reducer system is isolated from the drive shaft, the system is a two-inertia resonance system that should cope with an external load with the limited air-gap stiffness. On the other hand, the drive shaft or low-speed side is controlled only by the torque of the drive shaft through an air-gap, and the excessive oscillation or the slip can then be generated because of an abrupt disturbance that is different from the general mechanical gear system. Therefore, the disturbance loaded at the low speed side should be measured or estimated, and considered in the control of the driving shaft. This paper proposes a novel full-state feedback controller with a reduced-order observer for the speed reducer system using a magnet gear with a unified harmonic modulator. The control method was verified by simulation and experiment. To estimate the load at the low speed side, a novel observer was designed, in which the new state variable is introduced and the new state equation is formulated. Using a full-state feedback controller including the observer, the test result against disturbance was compared with two D.O.F PI speed controllers. The pole slip was compensated within relatively a short time, and the simulation result about the estimated variable shows a similar tendency to the test result. The test results showed that the magnet gear-based reducer can be applied to an accurate servo system.

호텔 식음료재료의 구매의사결정 영향요인에 관한 연구

정광석 ( Kwang Suk Jung ),장태진 ( Tae Jin Jang ),김기홍 ( Ki Hong Kim ) 한국호텔리조트카지노산학학회 2003 호텔리조트연구 Vol.1 No.1

The purpose of this dissertation is to provide to the suppliers who wants to sell their products to the hospitality industry understanding of the industrial buying behavior and the effective marketing strategies of hotel purchasing by analyzing their buying processes and behaviors. The literary review began with an examination of the characteristics of organizational buying behavior in conjunction with purchasing and management of the hospitality industry which had been shown in the previous study. Three influence variables affecting the buying behavior of the hospitality industry were proposed as: supplier selection criteria, the source of information, and the perceived risk. Survey questionnaires were mailed from other hotels of 250 members who take charge of purchasing job nowadays. A total of 112 usable response were received. Finally, the empirical findings of this study are summarized as follows: While most of the previous studies concerned with purchasing for the hospitality industry have been treated in terms of cost control and quality control, this study has examined the influential factors on purchasing decisions of the hospitality industry for the first time. Secondly, though selecting hotel material types, purchasing situation, hotel rank and purchasing center characteristics as the variables their inter-relational activities, this study gave the hotel industry a new way of research which had been domination on the manufacture industry.

여행도·소매업간의 유통시스템 영향변수가 신뢰와 결속에 미치는 영향 연구

정광석(Kwang Suk Jung),이광선(Kwang Sun Lee),김종원(Chong Won Kim) 한국호텔관광학회 2001 호텔관광연구 Vol.3 No.3

The purpose of this is to focus on the relationship of trust and commitment between tour wholesaler and retail agent in the travel industry. In order to review the relationship of trust and commitment between tour wholesaler and retail agent, this study used the influence variables of travel distribution channels, such as retailer`s satisfaction to the tour wholesaler, the conveyance of useful information to the retailer`s, closer mutual communication with tour wholesaler, tour wholesaler reputation, and wholesaler opportunism behavior, suggested in the proceed researches. It was conducted a questionaire survey of merchandisers from 47 travel retail agents in Seoul, Incheon and Suwon city. And the final sample of 110 retail agent merchandisers was attained. For empirical survey, the data was analysed by using Path Analysis. As a result of analysis retailer`s satisfaction to the tour wholesalers, the conveyance of useful information, closer mutual communication, tour wholesaler reputation were shown positively to the level of trust of the wholesalers and direct influence to the trust. But tour wholesaler opportunism behaviors were show negatively to the level of retailers. Also the trust level to the tour wholesalers was revealed positively to the level of commitment of the wholesalers and direct Influence to the commitment. Another result of the this study is that the conveyance of useful information, closer mutual communication, wholesaler reputation of travel distribution channels Influenced positively to the commitment between tour wholesaler and retail agent directly without passing through trust. In conclusion, the implication of this study indicates that the importance of wholesalers well managing with retailer agent, wholesaler good reputation to the retailers and customers, conveyance of useful information, impacts positively to the trust of retail agents.

인덕션 방식을 이용한 평면 스테이지의 동특성 개선

정광석(Kwang-Suk Jung),박준규(Jun-Kyu Park),김효준(Hyo-Jun Kim) 제어로봇시스템학회 2009 제어·로봇·시스템학회 논문지 Vol.15 No.7

Instead of direct driving like BLDC, the induction principle is adopted as a driving one for planar stage. The stage composed of four linear induction motors put in square type is activated by two-axial forces; low-frequency attractive force and thrust force of the linear induction motors. Here, the modified vector control whose new inputs are q-axis current and de current biased to three phase current instead of d-axis current or flux current is applied extensively to overall motion of the stage. For the developed system, the precision step test and the constant velocity test are tried to guarantee its feasibility for TFT-LCD pattern inspection. However, to exclude a discontinuity due to phase shift and minimize a force ripple synchronized with the command frequency, the initial system is revised to the antagonistic structure over the full degree of freedom. Concretely describing, the porous air bearings guide an air-gapping of the stage up and down and a pair of liner induction motors instead of single motor are activated in the opposite direction each other. The performances of the above systems are compared from trapezoid tracking test and sinusoidal test.