Christian Diedrich

Coupling heterogeneous production systems by a multi-agent based cyber-physical production system

Todays increasing volatility of market demands and customer requirements are forcing industrial enterprises to realize and ensure an increased flexibility of production systems. Since current automation concepts and architectures for production systems do not provide the required flexibility sufficiently, new approaches have to be developed. This paper proposes an approach that implements the quickly evolving concept of Cyber-Physical Systems for the special case of production systems by means of software agents. A joined demonstrator of such Cyber-Physical Production System is described and used for the evaluation of the proposed multi-agent approach.

Field device integration

Today, the large number of different device types and suppliers within a control system project makes the configuration task difficult and time-consuming. Different tools must be mastered and data must be exchanged between these tools. In the end the consistency of data, documentation and configurations can only be guaranteed by an intensive system test requiring detailed specialist knowledge. A solution can be achieved by standardizing suitable interfaces. For the computable description of device parameters the so called electronic device description language (EDDL) is specified. The electronic device description is used for the configuration and the operational behavior of a device. Furthermore, the field device tool (FDT) concept defines the interfaces between device-specific software components (device type manager-DTM) provided by the device supplier and the engineering tool of the control system manufacturer. A DTM can easily be developed using existing EDD files as shown in this article. So EDD and FDT are not contradictory technologies, but complement each other.

Field device integration in DCS engineering using a device model

Digital based actuation and measurement along with digital communication between field devices and DCS systems require an integration strategy for the engineering process of these systems. The field devices offer diagnosis, maintenance and pre-processing functions in addition to the former 4-20 mA technology. This results in an allocation of functions of the DCS system into field devices. This means that the design, commissioning, configuration, operator and visualisation tools perform an information flow based on a common data/information model. This paper describes the requirements for a device model and its use from different agents of the DCS or supervision system. The device model is specified in the object-oriented technique (with parts of UML). The device model is compared with existing device description languages (DDL) on the market like HART DDL, PROFIBUS Device Descriptions and Foundation Fieldbus DDL. The device model is used by tools which transform the electronic data sheets from the field devices to the interfaces of the DCS systems. This architectural view to the device description technology is discussed in this paper.

A migration approach towards a SOA-based next generation process control and monitoring

Interest in Service Oriented Architectures (SOA) in the automation domain has seen a rapid increase both from the academia as well as the industry recent years. Since green field plants today are not common, the partial migration of plant automation to SOA design is needed to introduce new functionalities. Thus strategies and approaches for migration from legacy to SOA architectures becomes of vital interest. This paper discusses different views on partial migration of a process monitoring and control system from legacy to SOA. The discussion includes a global top down view, a bottom up view, hardware/software considerations and a hint on training of personnel.

Cyber-physical systems alter automation architectures

Abstract Recent automation systems are well structured according to tasks fulfilled by the functions executed on dedicated devices. These functional assignments are also reasons for the design and topology of fieldbus communication systems. New approaches like Cyber Physical System (CPS) require different approaches according to existing communication technologies and engineering. On one side the interaction models advance, and on the other side the demands for industrial plants become a lot more flexible. This article shows upcoming demands on automation systems and discusses new strategies for software deployment of automation applications and communication systems to fulfill these requirements. This includes handling of different types of functional coupling, e.g. loose coupling with internet/web based technologies for interaction and information management. In addition the current device models offering specific device functions have to be adapted to the new CPS approach.

Integration of Legacy Devices in the Future SOA-based Factory

Abstract Future shop-floors are going to evolve as they need to be able to fully respond to dynamic adaptations and sophisticated interactions with the enterprise systems. This trend is fully backed up by the ever increasing capabilities of the new generation of devices that feature advanced communication as well as computational capabilities. However as the transition to the future infrastructure will be done progressively we need to make sure that the legacy devices can still be included and offer their benefits for non-interruptible business operation.

An agent-based platform for service integration in e-maintenance

The evolution of industrial systems makes the maintenance tasks more and more important. Encouraged by the requirements of industrial companies, we provide a solution to the problems of both industrial maintenance and enterprise integration by integrating industrial systems and field devices. With agent, Web and other technologies, e-maintenance and e-enterprise are becoming possible. E-maintenance is considered as one example of e-enterprise. A dynamic system model is constructed by extracting sources and targets, goals, and maintenance processes in terms of information flow between information nodes. An agent-based platform architecture seeks to integrate industrial systems in terms of e-maintenance, e.g., data acquisition systems, expert systems and business management systems.

Integration of fieldbus systems into on-line asset management solutions based on fieldbus profile descriptions

The use of fieldbus installations enables access to device information important for advanced functions like synthesizing plant data for asset management. Until now, this information is used only inadequately, since this information can only be integrated into existing applications with considerable expenditure. The paper shows an object-oriented asset management solution based on fieldbus profile descriptions. It realizes an additional, self-configuring information channel between field and plant control level. Clients can access application modules via TCP/IP networks. These modules can be loaded dynamically at run time. They implement enhanced functionality suitable for asset management tasks.

Function block applications in control systems based on IEC 61804

A variety of fieldbus technologies and digital fieldbus devices have been introduced within the process industries over the last ten years. There has been a gradual acceptance of the fact that a variety of communication technologies are needed to fully address the application requirements of a manufacturing facility. However, engineers responsible for the specification, engineering, and implementation of control systems require that a common interface and functionality be provided in the control system. This capability should be independent of the underlying fieldbus technology or manufacturer of the fieldbus device. The draft IEC 61804 standard defines how a control system can be structured to provide this flexibility in the utilization of fieldbus technology. In this paper, we discuss how a consistent function block capability may be provided for all fieldbus technology utilized in a control system. Examples will be given of how this standard has been applied in modern control systems to give a consistent interface to Foundation Fieldbus and PROFIBUS. Some detail will be presented on the standard means that is defined for manufacturers to describe function block capability of a field device. An analysis is given of the impact and benefit that the IEC 61804 standard will have on the process industry and on manufacturers of control systems.

Bedeutung der Interoperabilität bei Entwurf und Nutzung von automatisierten Produktionssystemen

Zusammenfassung Die strukturelle und verhaltensbezogene Komplexität von Produktionssystemen und ihrer Entwurfsprozesse stieg in den letzten Jahren kontinuierlich an. Daher ist es notwendig, diese Systeme bezüglich ihrer Nutzbarkeit und Veränderbarkeit auf neue Art und Weise zu bewerten. Ein Mittel für diese Bewertung ist die Untersuchung der Integration und Interaktion der Elemente von Produktionssystemen und Entwurfsprozessen. Auf ihrer Basis können neue Wege zur Verbessung der Struktur und des Verhaltens dieser Systeme und Prozesse entwickelt werden. Im Rahmen dieses Fachartikels werden unterschiedliche Integrationsgrade, darunter auch die Interoperabilität, auf der Basis der Modellaspekte Syntax und Semantik in eine Integrationsmatrix eingeordnet. An zwei Beispielen wird aufgezeigt, welche Bedeutung die verschiedenen Integrationsgrade in der praktischen Anwendung besitzen. Abstract Complexity of the structure and the behaviour of production systems are increasing over the years. Thus, these systems have to be validated related to its functional and non-functional requirements. One mean for this evaluation is the consideration of integration and interaction between the different elements of production systems and engineering processes. Based on this concideration, new approaches for the improvement of strucures and behaviours of production systems and its engineering processes can be developed. The contribution investigates different integration levels based on syntax and semantic aspects of the system models exploiting a matrix representation. Two examples show the impact of the introduced integration levels for the applications.