Operative Verwendung merkmalbasierter Information in der Automatisierung

  • Operative use of property-based information in automation

Kampert, David; Epple, Ulrich (Thesis advisor); Diedrich, Christian (Thesis advisor)

Als Manuskript gedruckt. - Düsseldorf : VDI Verlag (2017)
Book, Dissertation / PhD Thesis

In: Mess-, Steuerungs- und Regeltechnik 1256
Page(s)/Article-Nr.: 1 Online-Ressource (X, 124 Seiten) : Illustrationen, Diagramme

Dissertation, RWTH Aachen University, 2017

Abstract

The work introduces a novel concept for communication of technical properties. This concept enables industrial automation systems to request information on technical properties from external system. The requests are implemented using IEC 61131-compliant programming. Theoretical basic aspects, the overall concept, and its integration in industrial automation are discussed. More and more devices and systems in industrial environments are getting connected to computer networks. This connectivity is usually exploited to access automation systems from the outside. However, even automation systems themselves may benefit from the accessibility of data by requesting information from external systems that improves their operation. For example, the controller of a plant may request required information for production of a product variant at the right time by itself, without the need of having the information sent to it. With today’s state of technology, requests of this kind are cumbersome to configure and maintain, and have very low flexibility. Connectivity with computer networks thus offers a great potential for automation, but brings along high efforts. The standardization of communication that originates from automation systems would greatly improve this situation. Technical solutions already exist, but corresponding semantical standards are lacking. The meaning of a piece of information from a remote system, e.g. information on a product property, has to be known in advance, which becomes increasingly complex with more connected systems. Since much of the information of interest is information on technical properties, these are the starting point of the introduced concept. Extensive definitions of technical properties are available today in form of standards (e.g. IEC 61360 or eCl@ss). Furthermore, there is a clear idea of how to model technical properties in scientific literature. However, there is currently no concept how to use this data for operative automation. Basis of this work is the current state if the art in science, technology and industrially applied standards. The first chapters of this work review this state with respect to the later introduced concept. Specifically, the theoretical basis of property models, information systems, practical aspects of property models, query languages, software-systems in industrial environments and programming of automation systems are introduced. From these, requirements on the concept and its implementation are derived. The initial step is the definition of a query language for technical properties that refers to the given meta-model of technical properties. The formal basis of this language is relational algebra. The language consists of basic operations, motivated by theoretical considerations and technical realization, and advanced operations, that are motivated by practical use and that utilize the basic operations. Consequently, the integration of respective queries in IEC-61131-compliant automation systems is discussed. The operations are specified as function block types, practically allowing to program queries by linking function blocks. Interfaces and execution semantics of the function blocks are defined. Finally, the design and integration of a server for processing the queries is discussed. The integration into the IT environment of industrial production facilities is accounted and the internal software architecture is discussed. The work is concluded by use case examples and a review of the concept.