In this paper we illustrate a compositional method for modeling the concurrent execution of working processes in flexible manufacturing systems (FMS) through a special class of Petri Nets that we call S 'PI?. In essence, this class is built from state machines sharing a set of places modeling the availability of system resources. The analysis of S ' P R leads us to characterize deadlock situati...

Assigning proper dispatching rules dynamically has been shown to enhance various performance measures for a flexible manufacturing system (FMS). To achieve this, real-time salient information of the system is extracted and then a rule’s dispatching mechanism is built for the scheduling task. For a dynamic scheduled FMS, two critical issues dominate the performance; the first is the selection of...

Scheduling is an important tool for a manufacturing system, where it can have a major impact on the productivity of a production process. In manufacturing systems, the purpose of scheduling is to minimize the production time and costs, by assigning a production facility when to make, with which staff, and on which equipment. Production scheduling aims to maximize the efficiency of the operation...

The present investigation presents a stochastic model for a flexible manufacturing system consisting of flexible machine, loading/unloading robot and an automated pallethandling device. We consider unreliable flexible manufacturing cell (FMC) wherein machine and robot operate under individual as well as common cause random failures. The pallethandling system is completely reliable. The pallet o...

This paper initially discusses the state-of-the-art and the current limitations in the modeling, scheduling and control of flexible automation. To model flexible automation, it is argued that the simulation tools must provide enhanced capabilities to consider both controller interactions and the flow of resources that support production. It is also demonstrated that scheduling and control must ...

In today's industrial world, demand nature is changing where the customers are looking for a high variety of products. In order to meet varying customer demands, the firms should be flexible enough to produce parts in an efficient way. The flexible manufacturing systems have emerged with the progress in manufacturing technology. A flexible manufacturing system (FMS) is a computer-controlled pro...

Flexible manufacturing systems (FMS) are very complex systems with large part, tool, and information flows. The aim of this work is to develop a knowledge-based decision support system (KBDSS) for short-term scheduling in FMS strongly influenced by the tool management concept to provide a significant operational control tool for a wide range of machining cells, where a high level of flexibility...

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 1 INTRODUCTION...............................................................................................................................1
 1.1
 DECISION SUPPORT SYSTEMS......................................................................................

Recently, Coloured Petri Nets (CPNs) have been widely used for modelling asynchronous discrete events exhibited in dynamic systems, while Fuzzy Petri Nets (FPNs) used for systems that involve approximate reasoning and uncertainty knowledge inference. In this paper, we propose a net-based structure, the so-called Fuzzy Coloured Petri Nets (FCPNs) to model both the dynamic behaviour and inexact p...

In this paper, a general approach is proposed for the computation of a liveness enforcing supervisor for the Petri net model of a flexible manufacturing system (FMS) prone to deadlocks. The proposed method is applicable to a lot of PN classes. A global sink/source place (GP) is used temporarily in the design steps and is finally removed when the liveness of the system is achieved. The aim is to...