Search results for "Computer-integrated manufacturing"
showing 7 items of 17 documents
Distributed intelligent control of exceptions in reconfigurable manufacturing systems
2003
In order to react to the continuous and unpredictable changes in product demand, in product variety, and in process technologies, reconfigurable manufacturing systems allow quick adjustment of production capacity and functionality by rearranging or changing their modular components. In this kind of system, operation management issues, such as exception handling policies, become more complex since correct reconfiguration strategies have to be selected. This paper explores the potential of the reconfigurability feature to be a basis for the development of new strategies to handle out-of-the-ordinary events in the production process; in particular, maintaining production flow when machine brea…
Reconfigurable control of robotized manufacturing cells
2007
This paper investigates the field of manufacturing system control. The addressed subject is indeed very fascinating, due to the importance that it has reached in the last decades both at research and industrial level. On the other hand, it seems to the author that most of the complexity intrinsic to the subject itself relies on the different meanings or levels of abstraction that both the terms ''manufacturing system'' and ''control'' may symbolize. The presented research aims to face the topic in a concrete fashion, i.e., by developing a control software system for a specific, although easy to be generalized, robotized manufacturing cell. Two different development methodologies, from the c…
A user-friendly control system to easy reconfigure a manufacturing cell
2006
Generic manufacturing enterprises need to interact with an environment characterized by a strong competition. In order to react to the mutable requests of market, control systems should confer to the manufacturing system capabilities for easy modifiability, and this can be achieved by reducing the necessary time to reconfigure the existing system. Following this main requirement, this paper presents a user-friendly control system that pursues three operational goals: - Ability to easy re-program the sequence of operations of the manufacturing equipments of a manufacturing cell; - Reconfigurability of the system, by allowing to add/remove a new/existing component in/from the manufacturing ce…
Real-Time Routing Selection in Flexible Manufacturing Systems
1993
Routing flexibility is one of the main peculiarities of Flexible Manufacturing Systems. This paper proposes three methods for real-time routing selection. The first one makes decisions comparing the current workload of machines in each alternative path. The second method considers the current workloads at the bottleneck machines in each allowed route. The third approach makes real-time decisions minimizing a merit index that represents a measure of the still required resource amount. The index is computed by short discrete-event simulation runs. Some case studies evaluate and compare the proposed approaches.
A hierarchic approach to production planning and scheduling of a flexible manufacturing system
1999
Abstract The paper deals with the problem of improving the machine utilization of a flexible manufacturing cell. Limited tool magazine space of the machines turns out to be a relevant bottleneck. A hierarchic approach for this problem is proposed. At the upper level, sets of parts that can be concurrently processed (batches) are determined. At the lower levels, batches are sequenced, linked, and scheduled. Methods taken from the literature are used for the solution of the latter subproblems, and an original mixed integer programming model is formulated to determine batches. The proposed methods are discussed on the basis of computational experience carried out on real instances.
An Agile methodology for Manufacturing Control Systems development
2007
Robotized manufacturing cells are required more and more often to process high variety of short life-cycle product. This increases the need for methods and techniques for easy reconfiguration of software programs running in Programmable Logic Controllers (PLC), i.e., devices able to control manufacturing systems. PLCs run embedded code characterized by a procedural nature that does not make it quite reconfigurable. In this paper we propose an AGIle COntrol System Development (AGICOSD) methodology that uses various practices of Agile software development methodologies and the Design By Contract (DBC) practice for modeling and programming manufacturing control systems. In this context we prop…
Long term capacity decisions in uncertain markets for advanced manufacturing systems incorporating scope economies
2002
Abstract By examining the literature in the field of manufacturing flexibility many researchers have located several form of flexibility by distinguishing them into strategic and operational flexibility forms. Furthermore, many measures and design methods have been proposed for flexible manufacturing systems. Surely scope economies are one of the most important strategic form of flexibility in manufacturing systems and their strategic impact has been acknowledged by the very beginning of the flexible manufacturing era. However, despite several researches are available to address scope economies measurement and design methodologies, very few researches investigate their economic convenience …