Distributed Manufacturing

A simultaneous presence in several regions and in different regional markets has become more and more essential for suppliers and manufacturers alike. These configurations are enforced by volatile market demands, fierce competition, and high innovation pressure in order to capture lasting advantages in efficiency. In particular companies that have experienced rapid international growth through mergers and acquisitions are suddenly faced with the challenges of structuring, managing and operating effectively a network of geographically dispersed factories with worldwide transfer of assembly and manufacturing operations for similar products between multiple production sites in different countries. This competitive global environment imposes the continuous need to identify and exploit new manufacturing paradigms, adapted methods and cutting edge technologies. Little attention has been paid so far to the fact that distributed manufacturing structures and their full advantages may be exploited best if concurrency of information flows and operations is strived for. The competitive power of distributed structures lies in their abilitiy to put entities all together and make the net concurrent customer-driven, involving organisation, processes and business models. As competition starts pressuring whole networks, fast linking and interoperability as well as adaptation abilities have become crucial attributes for manufacturing companies.

Trade barriers have largely been removed through free trade agreements and economic blocs, not only in Europe but also worldwide. Manufacturers are finding that their distinguishable markets are swiftly evolving into a single, global marketplace. This can create new business opportunities but, on the other hand, the domestic markets are no longer protected as more and more companies are competing internationally. To compete in this new scenario companies are increasingly focused on covering all aspects of the product development process as their core business and decentralising other tasks using business units which operate more or less independently. The product development process in extended enterprises is increasingly organised in networks of suppliers, manufacturers and users, evolving towards service companies.

The fast changing bordering conditions for industrial manufacturing systems have raised the need to increase manufacturing system flexibility regarding different types of flexibility. To enable this enhanced flexibility, manufacturing control systems must be changed resulting in new challenges which have to be tackled by management and engineers of the affected companies. In parallel, within information sciences new paradigms for structuring and implementing software systems must be developed which are also applicable to design and implementation of control architectures. This paper deals with the applicability of these new paradigms for structuring and implementing software systems to address recent challenges within the manufacturing industry. Therefore, the paradigms and challenges are described and mapped to each other.

Distributed Manufacturing is mostly associated with computing features and sophisticated software logics rather than with working environments concurrently used in distant locations. Nowadays, the global success of Web2.0 and, more specifically, social networking web applications are quite obvious. In fact, information and communication technology (ICT) users are creating web content, applications and online role-playing games with their own activities and related data in using web applications such as eBay®, Facebook, Second Life virtual environment, and World of Warcraft. In manufacturing, interests are quite different and therefore other solutions should contribute to overcome collaborative distance factors that are impeding an effective and efficient distributed collaboration. Using important existing options in this field, this chapter presents an overview on key developments and web applications in the area of distributed computing systems to support effective and efficient collaborative work carried out by different groups of people in different organisational units or companies with a strong focus on engineering communication.

Distributed automation is unthinkable without adequate communication. This fact was discovered quite early, and from the first ideas of computer integrated manufacturing onwards, the need for networks in automation has been addressed. This chapter reviews the history of fieldbus systems and the problems of standardization and sheds light on the complex variety of existing approaches. Furthermore, it will discuss the recent adoption of Internet technologies and Ethernet as automation network and the ongoing work to overcome its real-time limitations. Finally, we address evolution prospects and current research issues ranging from the apparent security problem and synchronization mechanisms in distributed systems to entirely new approaches like bionics-inspired concepts.

Facing the fast growing needs regarding flexibility and adaptability of manufacturing systems, the decentralization of manufacturing execution control has attained high importance. Hence, in recent years different research and development activities have tackled the problem of decentralizing manufacturing execution control and implementing these decentralized systems within control architectures. One major result of these activities is a set of design patterns describing possibilities for decentralization including the description of major entities and interaction schemas.

These activities have also shown that agent systems are an appropriate means for the implementation of decentralized manufacturing execution control systems. They cope with decentralization by nature and (especially in the case of the Foundation for Intelligent Physical Agents (FIPA) - compliant agents) provide appropriate means for the implementation of the internal behavior of entities and entity interaction.

In this chapter some major design patterns for decentralized manufacturing execution control systems are described and mapped to three major approaches with Product-Resource-Order-Staff Architecture (PROSA) and MetaMorph (both based on Holonic Manufacturing Systems) and PABADIS (Plant Automation Based on Distributed Systems), and which finally are compared. Exploiting this comparison the PABADIS’PROMISE (PABADIS based Product Oriented Manufacturing Systems for Reconfigurable Enterprises) architecture is described as an architecture trying to incorporate the advantages of the different approaches and avoid its disadvantages.

The importance of European manufacturing remains high for the European economy as it still accounts directly for 22% of EU Gross Domestic Product (GDP), while it is estimated that 75% of EU GDP and 70% of jobs indirectly depend on the manufacturing sector. Facing intense global competition, the European manufacturing sector has to increase its flexibility and promote advanced business models involving the customer in all phases of the product lifecycle, such as mass customization. Distributed Automation Systems enable the enforcement of such models. Formerly physically centralized hardware and software is distributed in smaller units within the automation system. Advanced control devices relying on a common modeling paradigm may be used in order to provide intelligence at the field/control level. On the other hand, autonomous acting systems may provide the needed middleware for enabling flexible manufacturing systems.

Design patterns are an appropriate means to code solution knowledge within different areas of science and practice. They cover a description of the problem with the problem context, a description of a possible solution to the problem, and ancillary conditions of this solution. Initially design patterns were invented in the building architecture sciences but were quickly applied to information science and other disciplines.

This paper deals with the possible application of design patterns within industrial control. It describes how design patterns can be used by the example of design patterns for industrial field control systems. Therefore, initially the paper presents requirements for field control systems, maps the design pattern approach to them, and describes three basic design patterns for distributed field control systems.

This edited book has presented a selected range of contributions, based on the results of the EU Plant Automation Based on Distributed Systems (PABADIS) and PABADIS based Product Oriented Manufacturing Systems for Re-Configurable Enterprises (PABADIS’PROMISE) projects: from methodological to theoretical to address the issues surrounding Distributed Manufacturing. The contributions neither claim to have completed all the research necessary on the field nor to be the final stage of development of principles, methods and instruments resulting from network thinking in manufacturing. It must be noted that the “distributed” perspective on manufacturing, implicitly introducing the modes of iteration, parallelism, emergence, behaviour and encapsulation, reveals a surprising number of novel functions, creates new problems for methodologists, and generates demands for better information and communication technologies (ICT) pervasion. However, for now this recognition can only partly result in coherent descriptions of relevant (interdisciplinary) contributions for Distributed Manufacturing.

This volume will not conclude without an attempt to synthesise all approaches outlined and to summarise key challenges that further research needs to address in Distributed Manufacturing and the implications that this way of interpreting manufacturing and resulting research has on practice.