20 research outputs found
Towards formal monitoring of workpieces in agile manufacturing
No full textInformation about the locations of objects is one of the main ingredients of Industry 4.0. With the increased use of flexible and agile manufacturing techniques, the monitoring of workpieces in a factory can become more challenging. In this paper, we present a state-machine-based approach for monitoring workpieces using sensors such as RFID readers. We present a solution where each object is represented as a deterministic state machine to monitor the object's journey throughout production via this state machine representation. Multiple objects can be monitored at the same time by running parallel event-based state machines. We present an implementation of our solution using RFID-Readers and OPC UA.Peer reviewe
Digital Twins for Manufacturing Using UML and Behavioral Specifications
No full textUsing digital twins, physical manufacturing objects can be virtualized and represented as digital models which are seamlessly integrated in both the physical and the digital space. This allows to simulate, verify and optimize production systems, from the logistical aspects to the manufacturing process and the involved components. A key challenge, in this area, is how to describe digital twins in complex manufacturing systems such that all physical details, processes, and verification needs are modeled at an appropriate and efficient abstraction level, e.g., modeling and detecting divers faults in production processes. To address this challenge, in this paper we present our work on modeling digital twins of manufacturing facilities using UML. UML class diagrams are used to describe static dependencies between entities, as well as to monitor and analyze the dynamic verification and quality aspects of manufacturing such as fault detection and consistency checks. Utilizing the key relevant features of UML in our approach, the designed class diagrams are used and enriched with behavioral models serving as digital twins which can be updated by live data from the manufacturing plant. We present a small example based on simulation programs and a demonstrator. The presented modeling approach and example provide useful insights to UML-based design of digital twins in complex manufacturing systems.Peer reviewe
Generating an industrial process graph from 3D pipe routing information
No full textThe automatic generation of digital twins of industrial processes requires the integration of several sources of information. If the twin is expected to accurately capture thermo-hydraulic phenomena, dimensions of tanks and other process components as well as detailed pipe routing information is relevant. Such information is not comprehensively captured in P&IDs (Piping & Instrumentation Diagrams), but it is available from 3D CAD models. However, information about control loops is not available from 3D CAD models, but is available from P&IDs. Previous research has demonstrated the extraction of such information from machine-readable P&IDs and 3D CAD models and converting this information to graphs. Further research is expected on applying graph matching methods for integrating these separate graphs to a common graph-based data structure that captures all of the desired information. This common model could support further work to develop digital twins. A major obstacle to this is that the graphs that have currently been generated from P&IDs and 3D CAD models are at very different abstraction levels, so graph matching methods are not feasible. This article address this obstacle by building on previous work, in which graphs were generated from P&IDs and 3D CAD models. The contribution of this paper is several novel algorithms for preprocessing a 3D CAD generated graph, until it is at the same level of abstraction as a P&ID generated graph of the same industrial process. The algorithms are demonstrated in the context of a laboratory process.Peer reviewe
Mirrorlabs - Creating accessible Digital Twins of robotic production environment with Mixed Reality
No full textHow to visualize recorded production data in Virtual Reality? How to use state of the art Augmented Reality displays that can show robot data? This paper introduces an opensource ICT framework approach for combining Unity-based Mixed Reality applications with robotic production equipment using ROS Industrial. This publication gives details on the implementation and demonstrates the use as a data analysis tool in the context of scientific exchange within the area of Mixed Reality enabled human-robot co-production. Accepted Author ManuscriptMechatronic DesignTechnical SupportInternet of Thing
Sitting on a gold mine: the story of the process industry's automatic formation of a digital twin
No full textThe use of a software tool chain to generate Digital Twins (DTs)
automatically can speed up digitization and lower development costs.
Engineering documents and system data are just two examples of source
information that can be used to generate a DT. After proposing a general plan
for semi-automatic generation of a DT for a process system, this work describe
our efforts to extract necessary information for the generation of a DT of a
process system from existing information in a factory floor like piping and
instrumentation diagrams (P&IDs). To extract initial raw model data, techniques
such as image, pattern, and text recognition can be used, and then an
intermediate graph model can be generated and modified based on requirements.
In order to increase the system's adaptability and reliability, this research
will delve deeper into the steps involved in creating and manipulating an
intermediate graph model
Digital Twin-Assisted Controlling of AGVs in Flexible Manufacturing Environments
No full textPublisher Copyright: © 2021 IEEE.Digital Twins are increasingly being introduced for smart manufacturing systems to improve the efficiency of the main disciplines of such systems. Formal techniques, such as graphs, are a common way of describing Digital Twin models, allowing broad types of tools to provide Digital Twin based services such as fault detection in production lines. Obtaining correct and complete formal Digital Twins of physical systems can be a complicated and time consuming process, particularly for manufacturing systems with plenty of physical objects and the associated manufacturing processes. Automatic generation of Digital Twins is an emerging research field and can reduce time and costs. In this paper, we focus on the generation of Digital Twins for flexible manufacturing systems with Automated Guided Vehicles (AGVs) on the factory floor. In particular, we propose an architectural framework and the associated design choices and software development tools that facilitate automatic generation of Digital Twins for AGVs. Specifically, the scope of the generated digital twins is controlling AGVs in the factory floor. To this end, we focus on different control levels of AGVs and utilize graph theory to generate the graph-based Digital Twin of the factory floor.Peer reviewe
Integrating 2D and 3D Digital Plant Information Towards Automatic Generation of Digital Twins
No full textOngoing standardization in Industry 4.0 supports tool vendor neutral representations of Piping and Instrumentation diagrams as well as 3D pipe routing. However, a complete digital plant model requires combining these two representations. 3D pipe routing information is essential for building any accurate first-principles process simulation model. Piping and instrumentation diagrams are the primary source for control loops. In order to automatically integrate these information sources to a unified digital plant model, it is necessary to develop algorithms for identifying corresponding elements such as tanks and pumps from piping and instrumentation diagrams and 3D CAD models. One approach is to raise these two information sources to a common level of abstraction and to match them at this level of abstraction. Graph matching is a potential technique for this purpose. This article focuses on automatic generation of the graphs as a prerequisite to graph matching. Algorithms for this purpose are proposed and validated with a case study. The paper concludes with a discussion of further research needed to reprocess the generated graphs in order to enable effective matching.N
