• 한국추진공학회지
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• 제24권2호
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• pp.52-60
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• 2020

본 논문에서는 개방형 액체로켓엔진의 제어 알고리즘을 다룬다. 이를 위해 엔진의 각 구성품들을 기준으로 수학적 모델링을 하였으며 추력제어를 위하여 연소실 압력을 피드백하여 제어시스템을 구축하였다. 제어시스템을 위하여 최대추력 상태에서 선형 모델을 이용하여 최적 출력피드백 LQ 추종 제어기를 설계하였으며 시뮬레이션을 통해 제어기의 성능을 검증하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.184-187
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• 1997

Coordinate measuring machines(CMMs) are used to obtain the dimensional information with micron accuracy. This paper is concerned with the development of the horizontal arm type coordinate measuring machine using open architecture controller. The coordinate measuring machine considered in this paper consists of three orthogonal axes in the x, y and z directions. Open architecture controller IS used to implement a measuring system which can be fulfill to various needs of endusers of coordinate measuring machines. The open architecture controller presented here is embodied in personal computers. The programs and man-machine interfaces(MM1) are developed for various measuring conditions. Through the computer simulation based on the mathematical models of the coordinate measuring machine, control parameters are optimally tuned.

• 한국정밀공학회지
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• 제21권8호
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• pp.136-142
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• 2004

This paper deals with the design and implementation of an open architecture CNC system for Wire-EDM, with a consideration of the difference between Wire-EDM and NC cutting machines. Recent open architecture controller(OAC) related research results could be applied to directly access Wire-EDM systems at the CNC level. However, previous research about OAC is mostly aimed at NC cutting machines such as milling or lathes, and hence these results are inadequate to apply to Wire-EDM. To close the gap between previous general research on OAC and Wire-EDM specific needs, an open architecture NC model for Wire-EDM composed of a synchronization kernel and a NC functional module is proposed. Based on the control information flow and Wire-EDM specific machining process, the conceptual CNC model and the detailed implementation model for Wire-EDM is suggested.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.7-10
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• 2002

The diagnosis of faults of machine tool, which is controlled by CNC and PLC, is generally based on ladder diagram of PLC. Because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching for logical relation to fault reasons is required a lot of fault experiences and times, because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault lastly and correctly. The diagnosed reasons for fault are tele-serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• 한국정밀공학회지
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• 제20권10호
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• pp.89-97
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• 2003

The faults diagnosis of machine tool, which is controlled by CNC(Computer Numerical Control) and PLC(Programmable Logic Controller), is generally based on ladder diagram of PLC because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching of logical relationship for fault reasons is required a lot of diagnosis experiences and times because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault fast and correctly. The diagnosed reasons for fault are remote serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• 한국정밀공학회지
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• 제22권4호
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• pp.136-143
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• 2005

Open architecture controller (OAC) is well known technology in factory automation. To better understand the requirements of OAC, authors have discussed the OAC related topics with a number of control experts who represents different segments of the machining industry. There is no common concept that is accepted or used, however, the common ideas for OAC is the control system that is hardware independent, interchangeable, and easily scalable. This paper presents summary of the understaning and requirements of OAC. Based on the requirements of OAC, authors developed the software based PC-CNC. The main focus of the PC-CNC was on the user customization capability and open interface between control networks in manufacturing system. This paper introduces the developed PC-CNC briefly. In addition to introduction of the PC-CNC, to fill the gap between end users and vendors of OAC, this paper presents two applications using OAC. One is a remote monitoring system. The OPC (Ole for Process Control) standard interface was used to monitor the status of open architecture CNC across network. The other is the remote production management module for machine tools using standard database interface.

• 한국정밀공학회지
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• 제21권8호
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• pp.143-151
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• 2004

This paper deals with the precision NURBS interpolator for wire-EDM. Previous research about OAC (Open Architecture Controller) is mostly aimed at NC cutting machines such as milling or lathes, and hence these results are inadequate to apply to wire-EDM. In contradiction to NC machines, wire-EDM operates relatively slow feed rates and based on a feedback control loop to the machining process. The 2-stage interpolation method which reflects wire-EDM specific characteristics was proposed. The constant interpolation error could be acquired through 1 st stage interpolation. Feed rate regulation was performed through 2nd stage interpolation. The suggested algorithm was implemented to test-bed PC-NC system. Computer simulations and the experimental machining were conducted.