• 제어로봇시스템학회:학술대회논문집
• /
• 1991.10b
• /
• pp.1564-1569
• /
• 1991

In this paper we describe Flexible Manufacturing Systems (FMS) using Petri nets, since Petri nets provide a powerful tool for modeling dynamical behavior of discrete concurrent processes. We deal with off-Line and on-Line rule-based scheduling of FMS. The role of the rule-base is to generate appropriate priority rule for resolving conflicts, that is, for selecting one of enabled transitions to be fired in a conflict set of the Petri nets. This corresponds to select a part type to be processed in the FMS. Towards developing more Intelligent Manufacturing Systems (IMS) we propose a conceptual framework of a futuristic intelligent scheduling system.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.21 no.47
• /
• pp.193-209
• /
• 1998

The objective of this paper is to present a methodology for design of the FMS by using a new modeling tool which is called SE&TPN(Safe Extended & Timed Petri Net). A FMS, which consists of various machine groups, may produce machine parts in different physical dimensions and lot size. The approach involves the SE&TPN modeling by Petri-nets. The proposed algorithm can handle determining of firing count vector by incidence matrix and adjustment of conflict using the marking of SE&TPN. The SE&TPN is defined as nets that can have at most one token in one place and can have elements such as permissive arcs and inhibitor arcs in addition to elements. The SE&TPN with permissive arcs and inhibitor arcs are intuitively direct approach to increase the modeling power of the SE&TPN. Finally, this paper is to develop a modulation to optimize the system problems of FMS using SE&TPN which describes exactly features of Petri Nets.

• Journal of Korean Institute of Industrial Engineers
• /
• v.21 no.2
• /
• pp.153-165
• /
• 1995

Many closed queueing network models have been used as an effective tool to make a preliminary design of FMS. Although a loading/unloading function is an important factor to effect the utilization and throughput of FMS as well as a transfer function and a processing function, the Solberg's model did not clarify the loading/unloading function. In this paper, we propose a closed queueing network model for analyzing a flexible manufacturing system that consists of a load/unload station, a material handling system and a group of workstations for processing jobs, and define the expected utilization and the expected throughput of the FMS. As applications of the proposed model, the cases of a material handling system consisting of a conveyor and the FMS including an inspection station are also formulated.

• Proceedings of the KIEE Conference
• /
• 2005.07d
• /
• pp.2667-2670
• /
• 2005

In this Paper is analyzed about FMS(Fieldbus Message Specification) service of FOUNDATION Fieldbus and designed using of UML(Unified Modeling Language). The FMS provides a number of services for reading, writing, and otherwise accessing objects. The FOUNDATION Fieldbus protocol is object oriented. The information in the devices is accessed in the form of objects. In FMS, the objects for configuring device and strategy in a node are listed in an object dictionary(OD). Each object is identified by an index. For example, every function block and every parameter has an index.

• IE interfaces
• /
• v.1 no.2
• /
• pp.25-34
• /
• 1988

Simulation is known to be a valuable tool for design and operation of Flexible Manufacturing Systems(FMSs) under study. However, in order for simulation to be useful, lots of knowledges about the behavior of system to be designed, statistics for output analysis, modeling techniques and a specific simulation language are required by the simulationist. In this paper a way to build simulation support system for nonexperts at simulation will be described and a simulation support system for FMS design and operation developed by the authors will be demonstrated.

• Proceedings of the Korea Society for Simulation Conference
• /
• 1999.04a
• /
• pp.54-59
• /
• 1999

본 논문에서는 유연생산시스템 (FMS: Flexible Manufacturing System)의 객체지향 시뮬레이션(OOS: Object Oriented Simulation)에 대한 기존의 연구들을 소개한다. 먼저 FMS와 객체지향시뮬레이션의 일반적인 개념에 대해서 이야기하고 기존의 연구들을 대상 시스템의 추상화(abstraction)과정을 중심으로 분류하여 정리하였다. 추상화 방법론과 FMS를 위한 객체지향시뮬레이션의 현황 및 과제에 대해서도 간략하게 살펴보았다.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1995.10a
• /
• pp.1186-1190
• /
• 1995

This paper is focused on the formulation of explicit closed-form functions describing the performance measures of the general flexible manufacturing system (FMS)according to the strategy of material handling system(MHS). the performance measures such as the production rate, the production lead-time and the utilization rate of the general FMS are expressed, respectively, as the explicit closed-form functions of the part processing time, the service rate of the material handling system (MHS) and the number of machine tools in the FMS. For this, the gensral FMS is presented as a generalized stochastic Petri net model, then, the moment generating function (MGF) based approach is applied to obtain the steady-state probabity formulation. Based on the steady-state formulation, the explicit closed-form functions for performance measures of the probability FMS can be obtained. Finally, the analytical results are compared with the Petri net simulation results to verify the validity of the suggested method. The paper is of significance in the sense that it provides a comprehensive formula for performance measures of the FMS even to the industry engineers and academic reademic resuarchers who have no background on Markov chain analysis method or Petrinet modeling

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1995.04a
• /
• pp.111-120
• /
• 1995

통합생산시스템에서의 고장, 정비 및 가용 도는 매우 중요한 역할을 한다. 시스템 설계시의 RAM 파라메터의 결정은 시스템의 성능과 소요비용 및 구성(System Configuration)등에 크게 영향을 미친다. 이러한 시스템관련 요소의 숫자가 많거나 불확실할 경우는 시스템의 성능예측이 매우 복잡하게 된다. 이러한 시스템의 성능(performance) 평가를 위하여 발견적 방법인 GMDH(Group Method Data Handlinng) Type Modeling 방법을 이용하여 FMS의 성능 평가를 시도하였다. RAM 및 기계작업시간의 Data로부터 시스템성능의 척도로서 단위 사이클 기간동안의 생산률, 시스템내의 총 흐름시간, 각 작업장이 기계의 RAM 및 LCC등을 고려하였다. GMDH 알고리즘의 계산을 위한 프로그램을 개발하고, 이를 L형 Bracket제조시스템의 성능 예측에 시험 적용하였다. 본 Modeling에 의한 시스템의 성능예측 방법은 입출력 자료의 처리과정을 개선할 경우 FMS계획및 운영 단계에서 성능평가에 매우 유용하게 활용될수 있을 것으로 본다.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1992.04b
• /
• pp.436-443
• /
• 1992

Presented in the paper is a systematic approach to constructing a Petri net model of FAS (flexible assembly system). Petri net is widely used in modeling automated manufacturing systems. But, it found to be very difficult for an FA engineer to build a correct model of an FAS with Petri net symbols (ie, place, transition, and token) from the beginning. An automated manufacturing system in general is built from a set of "standard" hardware components. An FAS in particular is usually composed of assembly robots, work tables, conveyor lines, buffer storages, part feeders, etc. In the proposed modeling scheme, each type of standard resources is represented as a standard "module" which is a sub Petri net. Then, the model of a FAS can be conveniently constructed using the predefined modules the same way the FAS itself is built from the standard components. The network representation of a FAS is termed a JR-net (job resource relation net) which is easy to construct. This JR net is then mechanically converted to a formal Petri net (to simulate the behavior of the FAS). The proposed modeling scheme may easily be extended to the modeling of other types of automated manufacturing systems such as FMS and AS/RS.ch as FMS and AS/RS.

• Korea Information Processing Society Review
• /
• v.11 no.1
• /
• pp.8-19
• /
• 2004

Many Researchers and practitioners have expressed the view that artificial intelligence(AI) may have significant application to solution of manufacturing problems. Expert systems have been developed for solving problem areas.(omitted)