• Journal of the Korean Society for Precision Engineering
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• v.3 no.2
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• pp.16-27
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• 1986

The problems concerning FMC (Flexible manufacturing cell) system layout were treated in this paper. In fact, there being no clear definition about FMS (Flexible manufacturing system), it could be treated as the system adopting flexible-automation and FMS has been improving as a form of parts machining system. It was thought that the problems of combination of machine tool groups and parts family were important. Parts familly and machine tool groups were made up by means of multivariate analysis and the minimum trnsfer concept using correlation coefficient ($\rho$). And FMC system was layout by directional graph according to the FMS classifications.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1992.10a
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• pp.243-248
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• 1992

Computer Integrated Manufacturing(CIM) is a growing technology as a solution for the total automation of a manufacturing system. However, the implementation in the shop floor is extremely difficult due to many reasons. Flexible Manufacturing System (FMS) is usually considered as a solution for the shop floor automation. One of the difficulties in FMS is the communications problem. Since various machinaries with different communications protocols are included, applying a unified scheme is almost impossible. Therefore, a systematic approach is a key point to solve the communication problem. A cell is defined as an automation unit where closely related for a job reside together. A cell is a messenger between upper level computers and lower level machine equipment. In this research, the functions of the cell are defined to have more capabilities than conventional cell since a cell can be often a total manufacturing system in a small to medium sized factory. The cell conducts communications with different machines through the communications schemes established here. A set of software system has been developed according to the defined communications. The software has been tested for a simulation and real experiments for proof.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.4
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• pp.658-665
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• 1994

CIM is generally considered as a solution for total automation of a manufacturing system. In a CIM system, Flexible Manufacturing System(FMS) is linked colsely to the actual manufacturing line. This study will examine the strategy of integrating incompatible FA equipments, expecially PLCs (Programable Logic Controllers). PLC Manager is proposed as a model for integrating PLC algorithms, whose primary tasks are to communicate line-field data with PLCs and cell controller. To operate it, a PLC script language is designed and implemented.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.105-106
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• 2013

• Journal of the Korean Society for Precision Engineering
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• v.11 no.5
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• pp.75-87
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• 1994

The demand for automatic manufacturing systems is increasing. One of the crucial obstacles to the Flexible Manufacturing System(FMS) is the lack of excellent strategies for efficient operations. The aim of this research is constructing an automaton scheme in the low level of factories where various machineries are involved. An operating strategy is established for an automation unit named as a cell which resides between the upper level computers and manufacturing shop floor. The cell is defined to fit into the total manufacturing system. The defined cell has more functions than conventional cells. A scheduling scheme is adopted for the shop floor operations. A set of software has been developed and tested through simulations and shop floor experiments.

• Management Science and Financial Engineering
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• v.3 no.1
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• pp.15-38
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• 1997

In a flexible manufacturing system, a cell controller is able to identify and evaluate a number of alternative decisions to meet the objectives set by the factory level controller. In this paper, a Petri net-based cell controller is presented to accomplish this task. A static model is developed by using the Integrated Computer Aided Definition(IDEF0) method to represent clear functional relationships among the objects of the system. Based on the static model, two Petri net models are developed for the physical part flow and for the information flow. Multiple decision alternatives are generated from the physical part flow model and are synchronized with the information flow model for execution of the selected alternative.

• Proceedings of the Korea Society for Simulation Conference
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• 1998.10a
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• pp.128-132
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• 1998

This research is concerned with buffer management in a multi-cell FMS(Flexible Manufacturing System) with an AGVS(Automated Guided Vehicle System). To reduce blocking and starving caused by breakdowns, variablility in process times, and diversity of part routing, buffer is needed. Due to the high per unit buffer cost, which primarily consists of floor space and equipment cost, the total capacity of buffers in an FMS is very limited. Therefore, proper buffer management can provide a high system efficiency. This paper presents a buffer management model for a multi-cell FMS with an AGVS and a simulation study to compare the proposed model to a conventional buffer management model in a job shop FMS.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.3
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• pp.492-503
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• 1994

In this study, the control and scheduling of the flexible manufacturing cell (FMC) is discussed, which can perform the mixed production and relieve the effect of machine failure. The control of the FMC isvery complex task due to the property of multiple jobs and the dynamically changing states. For effective control of proposed FMC, the hierarchical scheme is introduced and the functions of each levels are defined. Especially for the control functions of shop floor level and cell level, the intelligent scheduler is implemented. To show the efficiency of the intelligent scheduler, the production method fo the existing assembly lines was evaluated and compared with the proposed intelligent FMC method. The results from the production performance show that the proposed method is superior to the existing method in various performance indices.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.561-563
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• 1997

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.564-566
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• 1997