Fraunhofer-Institut für Optronik, Systemtechnik und Bildauswertung IOSB

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  • Publication
    Modellbasierter Entwurfsassistent zur Auslegung spezifischer Architektur- und Konfigurationseigenschaften von Kommunikationsnetzen mit Echtzeitanforderungen
    ( 2016)
    Leßmann, Gunnar
    ;
    Schneider, Daniel
    ;
    Flatt, Holger
    ;
    Schriegel, Sebastian
    ;
    Jasperneite, Jürgen
    Industrielle Netzwerke werden immer komplexer durch den Einsatz neuer Technologien wie Time Sensitive Networking (TSN). Die Anforderungen werden zudem verschärft durch sich ändernde gesetzliche Vorgaben wie z.B. bei Smart Grids. Planer solcher Netzwerke haben häufig spezifische Echtzeitanforderungen, Datenraten und Redundanzanforderungen zu beachten, deren Realisierung u.a. abhängig sind von der Leistungsfähigkeit und der Topologie des Netzwerkes. Designalternativen sollten daher quantitativ bewertbar sein, um individuelle Planungsaspekte erweiterbar sein und eine generelle Anwendbarkeit aufweisen. Da diese Kriterien aktuell von keinem verfügbaren Planungswerkzeug erfüllt werden, wurde in diesem Beitrag mit Hilfe von Matlab Simulink® ein generisches und skalierbares Modell von Netzwerkkomponenten erstellt. Diese Komponenten können parametriert und in einer anwendungsnahen Topologie kombiniert werden. Leistungsqualifizierende Parameter wie die Echtzeitfähigkeit, Auslastung der Komponenten, Ausfallsicherheit und die Topologie wurden zur Bewertung von Designszenarien eines beispielhaften Windparks herangezogen. Eine Erweiterung des Modells ermöglicht es darüberhinausgehend die Auswirkungen von zukünftigen Technologien, wie z.B. TSN zu analysieren.
  • Publication
    Automatic determination of synchronization path quality using PTP bridges with integrated inaccuracy estimation for system configuration and monitoring
    ( 2015)
    Schriegel, Sebastian
    ;
    Biendarra, Alexander
    ;
    Ronen, Opher
    ;
    Flatt, Holger
    ;
    Leßmann, Gunnar
    ;
    Jasperneite, Jürgen
    Many network applications like motion control or precise monitoring of machines need precise knowledge about the time synchronization accuracy. But time synchronization accuracy depends on the performance of PTP nodes, network topology, environmental conditions and various other factors. This makes the determination of synchronization accuracy a complex task. A mechanism for determining the worst case synchronization accuracy is defined in the PTP Power Profile. A TLV is used for accumulating a vendor defined worst case inaccuracy. However in practice when using this approach the inaccuracy values are often much higher than the real synchronization accuracy. In this paper, a technique for automatic determination of synchronization path quality is investigated. It utilizes PTP Bridges with an inaccuracy estimation performed using an inaccuracy model that is separated into static and dynamic inaccuracy contributors. One assumption is that the inaccuracy in the PTP time observed by a bridge, depends on the position of the bridge in the sync path. The latter is due to accumulation of more, possibly independent, random contributors. The effect of increasing deviation is modeled and verified using an experimental setup. The paper concludes that detailed knowledge about the PTP network (cable lengths, inaccuracy contribution metrics for the specific nodes within the sync path, etc.) are useful for automatic determination of the synchronization path quality, synchronization monitoring, system configuration and diagnosis. We suggest an enhancement to the TimeInaccuracy TLV that may possibly be incorporated within the next PTP revision, to better facilitate the protocol support for the above functions.
  • Publication
    An OPC UA based approach for dynamic-configuration of security credentials and integrating a vendor independent digital product memory
    ( 2014)
    Blume, Marco
    ;
    Koch, Nils
    ;
    Imtiaz, Jahanzaib
    ;
    Flatt, Holger
    ;
    Jasperneite, Jürgen
    ;
    Schleipen, Miriam
    ;
    Sauer, Olaf
    ;
    Dosch, Steffen
    This paper presents an approach to securely integrate industrial devices into automation systems with a minimal engineering effort. A special specific focus is on the needed communication architecture that is based on the platform independent and vendor neutral technology OPC UA. The paper also describes the need of a digital product memory besides a life cycle data harvesting to facilitate such seamless integration; this is by means of presenting semantics of operations to an external system. As part of the work, a case study has been identified; different architectural aspects are evaluated and essential system components are realized/implemented/integrated as a proof of concept. Principle results include the implementation of a BeagleBone Black-based Secure Plug & Work I/O field device with an extended real-time industrial communication interface and a semantically enriched OPC UA server that provides vendor neutral configuration and an I/O data service interface. Furthermore, the result provides a platform independent and standardized way to represent a field device to external systems, to enable intelligent technical systems to communicate and orchestrate a seamless and secure integration.
  • Publication
    Versatile assembly systems - requirements, design principles and examples
    ( 2014)
    Hinrichsen, Sven
    ;
    Jasperneite, Jürgen
    ;
    Schrader, Florian
    ;
    Lücke, Benedikt
    The requirements of assembly systems are changing, due to trends such as shorter innovation and product lifecycles as well as an increase in the number of product variants and product customization. Certain markets are characterized by demand volatility and short delivery schedules. As a result of shortened product and innovation lifecycles and demand volatility, the assembly system design should be versatile. The aim of this paper is to demonstrate a versatile assembly system which was jointly developed by the Fraunhofer IOSB-INA and the Ostwestfalen-Lippe University of Applied Sciences.
  • Publication
    Service-oriented architecture for the autoconfiguration of real-time ethernet systems
    ( 2012)
    Dürkop, L.
    ;
    Imtiaz, J.
    ;
    Trsek, H.
    ;
    Jasperneite, Jürgen
    In the context of flexible and agile manufacturing systems, the autoconfiguration capability of devices is very important. Besides other advantages, a Service-Oriented Architecture (SOA) could support the autoconfiguration by offering several interesting features. The Devices Profile for Web Services and OPC Unified Architecture are promising candidates for a future deployment in industrial automation, due to their specific characteristics. However, resource constraint embedded devices, such as low cost field devices, face particular challenges for an SOA implementation in terms of required memory resources. In this work both technologies are introduced and implemented on embedded devices. The focus is put on autoconfiguration of real-time Ethernets. A comparison and analysis of both solutions, using the discovery process as an example, show their main differences. Finally, the advantages and drawbacks of both approaches are discussed based on the previous findings.