@inproceedings{SchmidGalkaMarinkovicetal., author = {Schmid, Florian and Galka, Stefan and Marinkovic, Minja and Meißner, Sebastian}, title = {Simulationsbasierte Untersuchung von Abstraktionsgraden im Kontext Digitaler Zwillinge f{\"u}r innerbetriebliche Transportsysteme}, series = {Tagungsband 20. ASIM-Fachtagung Simulation in Produktion und Logistik, Ilmenau, 13. - 15. September 2023}, booktitle = {Tagungsband 20. ASIM-Fachtagung Simulation in Produktion und Logistik, Ilmenau, 13. - 15. September 2023}, editor = {Bergmann, S{\"o}ren and Feldkamp, Niclas and Souren, Rainer and Straßburger, Steffen}, publisher = {Universit{\"a}tsverlag Ilmenau}, address = {Ilmenau}, isbn = {978-3-86360-276-5}, doi = {10.22032/DBT.57794}, pages = {135 -- 144}, abstract = {Current challenges in the planning and control of internal logistics systems are based on permanent changes in the requirements on the system, e.g., due to fluctuating order numbers or changes in their structure. For the representation and planning of in-house logistics processes, digital twins offer the possibility to verify different operational decisions such as predictive workforce scheduling. In this context, the quality of the results and their in-time presentation plays a decisive role. However, both target criteria are influenced by the detail-level of the digital representation. Based on a case study, this paper investigates the influence of the level of detail on the simulation runtime and result divergence to provide an evaluation for detail levels in the modelling of intralogistic transport systems.}, language = {de} } @inproceedings{GalkaSchmidGrasseretal., author = {Galka, Stefan and Schmid, Florian and Grasser, Dominik and Hohm, Jonathan and Stauber, Stephan and Meißner, Sebastian}, title = {Integration eines SAP-Transportleitsystem in eine Simulationsumgebung zur Unterst{\"u}tzung von Entscheidungen im operativen Betrieb}, series = {Tagungsband 20. ASIM-Fachtagung Simulation in Produktion und Logistik, Ilmenau, 13. - 15. September 2023}, booktitle = {Tagungsband 20. ASIM-Fachtagung Simulation in Produktion und Logistik, Ilmenau, 13. - 15. September 2023}, publisher = {Universit{\"a}tsverlag Ilmenau}, address = {ILmenau}, isbn = {978-3-86360-276-5}, doi = {10.22032/DBT.57813}, pages = {281 -- 291}, abstract = {Digital twins enable the digital representation of physical systems and provide comprehensive modelling and analysis capabilities. An online data exchange between the Digital twin and SAP is feasible, through integration of a transport control systems (SAP) via RESTful API. This interface allows decision making in resource allocation and furthermore the adaptation of the digital model if the real system changes. Despite the associated challenges in terms of data synchronisation, the integration has benefits such as a reduction in modelling effort and an increase in the lifetime of the digital twin. In the context of this work, the design of the interface between the simulation software and a SAP transport control system via RESTful API is described.}, language = {de} } @inproceedings{GalkaWeigert, author = {Galka, Stefan and Weigert, Alexander}, title = {Systematik zur planungsbegleitenden Simulation bei der Konzeptplanung von Produktionssystemen - ein Anwendungsfall aus der Elektrolysestack-Produktion}, series = {Simulation in Produktion und Logistik 2025}, booktitle = {Simulation in Produktion und Logistik 2025}, editor = {Schmidt, Thorsten and K{\"u}hn, Mathias and Rank, Sebastian}, publisher = {Technische Universit{\"a}t Dresden, Professur f{\"u}r Technische Logistik}, address = {Dresden}, isbn = {978-3-86780-806-4}, doi = {10.25368/2025.278}, pages = {45-1 -- 45-10}, abstract = {Simulation can support early-stage production system planning by enabling efficient evaluation of concept variants. However, detailed models are often impractical in concept phases due to limited data and high modelling effort. This paper presents a structured three-stage simulation approach for supporting the concept planning of water electrolyzer stack production systems . The approach leverages automatic model generation from formal process descriptions and gradually increases model detail across stages, carried out through a custom-developed simulation framework. This enables early validation of the throughput capability, resource planning, and the analysis of stochastically occurring technical malfunction. The method aims to reduce planning time while improving decision quality.}, language = {de} } @inproceedings{GalkaMeissner, author = {Galka, Stefan and Meißner, Sebastian}, title = {Einsatz von Digitalen Zwillingen f{\"u}r die operative Steuerung von innerbetrieblichen Transportsystemen}, series = {Simulation in Produktion und Logistik 2025}, booktitle = {Simulation in Produktion und Logistik 2025}, editor = {Schmidt, Thorsten and Rank, Sebastian and K{\"u}hn, Mathias}, publisher = {Technische Universit{\"a}t Dresden, Professur f{\"u}r Technische Logistik}, address = {Dresden}, isbn = {978-3-86780-806-4}, doi = {10.25368/2025.280}, pages = {47-1 -- 47-11}, abstract = {This paper presents the architecture and functionality of a simulation-based Digital Twin designed to support decision-making in the control of internal transport systems. The developed Digital Twin leverages a wide range of data from operational information systems to predict future system loads. Specific methods for forecasting transport orders have been developed. An integrated simulation framework enables analysis of potential control decisions, such as resource allocation or the timing of order releases. The simulation results are used for multi-criteria evaluation of the available options for preventive action, thus, providing users with concrete recommendations to support their operational decision-making processes.}, language = {de} } @inproceedings{GalkaWeigert, author = {Galka, Stefan and Weigert, Alexander}, title = {Petri Net Structures for Automated Model Generation through Process Descriptions}, series = {IFAC Papers OnLine}, volume = {59}, booktitle = {IFAC Papers OnLine}, number = {10}, publisher = {Elsevier}, doi = {10.1016/j.ifacol.2025.09.093}, pages = {542 -- 547}, abstract = {Creating simulation models and running experiments requires expertise and significant effort. Modelling complex production systems by using Petri Nets, which have a simple formalism, leads to considerable modelling effort. To reduce the workload required, fundamental processes within a production system must be analyzed and represented as generic Petri Net structures to enable their automatic generation. These structures can serve as modular building blocks to construct arbitrarily complex systems. The broader objective is to enable the automatic generation of such, based on process descriptions within a simulation framework. Built on these findings, the necessary information for developing a specialized formal process description is derived, enabling the automated generation of Petri Net simulation models for production systems.}, language = {en} } @inproceedings{Galka, author = {Galka, Stefan}, title = {Integration and usage of simulation-based digital twins in internal logistics systems}, series = {IFAC Papers OnLine}, volume = {59}, booktitle = {IFAC Papers OnLine}, number = {10}, publisher = {Elsevier}, doi = {10.1016/j.ifacol.2025.09.152}, pages = {897 -- 902}, abstract = {This paper presents the workflows of Digital Twins in practice, with reference to three case studies. The objective is to present the processing of data and information flow. The most essential requirements for the design of a Digital Twin are synthesized from the case studies and a layer model is presented, which was developed based on the three case studies. The model consists of four functional layers and an overarching data- and workflow-management-backbone. A front-end layer is proposed for communication with the end user.}, language = {en} } @article{GinsterWeigertHeymetal., author = {Ginster, Vinzenz and Weigert, Alexander and Heym, Maximilian Klaus and Beier, Christoph J{\"u}rgen Anton and Schiebahn, Alexander and Galka, Stefan}, title = {Factory simulation of adhesive bonding processes considering pot-life-induced waste}, series = {Journal of Advanced Joining Processes}, volume = {13}, journal = {Journal of Advanced Joining Processes}, publisher = {Elsevier}, issn = {2666-3309}, doi = {10.1016/j.jajp.2026.100375}, pages = {7}, abstract = {The simulation of production systems in the planning phase is an established tool for evaluating system performance under dynamic conditions (Da Silva et al., 2018). When planning a production system that includes time-critical processes such as adhesive bonding, exceeding time constraints (e.g., excessive lead times relative to the adhesive pot-life) can lead to product rejection and scrap. These risks should be analyzed by means of simulation, as it enables the consideration of stochastic effects such as random machine breakdowns, which significantly influence product lead times. This study focuses on the production of adhesively bonded electrolyzer-cells. Due to the cell design, several handling and stacking operations must be carried out between adhesive application and final joining, so that immediate joining is not feasible and pot-life-induced scrap becomes a critical risk factor. We therefore conducted an exploratory investigation that combines experimental pot-life characterization with discrete-event simulation of a planned electrolyzer-cell production system. A two-component epoxy adhesive was characterized using differential scanning calorimetry with kinetic analysis, rotational rheometry, and 90° peel tests on application-representative joints. Based on these tests, an application-specific pot-life was derived and implemented as a time-dependent quality criterion in the discrete-event simulation model. A full-factorial simulation study with varied buffer size and mean time to repair at a station availability of 98 \% was carried out. The results demonstrated a pronounced trade-off between throughput and pot-life-induced waste and identified a buffer capacity of one and short repair times as the most favorable configuration. Extending pot-life due to different processing temperatures substantially reduced scrap, highlighting the benefit of integrating curing kinetics and dynamic simulation in early-stage production system design for time-critical adhesive processes.}, language = {en} } @inproceedings{GalkaMeissner, author = {Galka, Stefan and Meißner, Sebastian}, title = {Simulation-Based Digital Twins for Internal Transport Systems}, series = {Procedia Computer Science}, volume = {274}, booktitle = {Procedia Computer Science}, publisher = {Elsevier}, doi = {10.1016/j.procs.2025.12.016}, pages = {161 -- 170}, abstract = {The increasing complexity of internal transport systems in industrial applications poses significant challenges for operational decision-making. This paper presents a simulation-based Digital Twin framework developed within the research project TwinTraSys to support the control of such systems. The framework is specifically tailored to the constraints of real-world IT infrastructures, requiring minimal transaction data, while enabling predictive analysis and dynamic scenario evaluation. It consists of a modular architecture divided into four core components: data provision, data preparation, simulation, and decision support. A dedicated simulation framework enables the automated generation of structural models and the integration of real-world operational control systems. The proposed approach has been validated in industrial settings and has demonstrated its ability to support resource planning and transport resource allocation through simulation-based experimentation and multi-criteria evaluation. This paper contributes to the practical advancement of Digital Twin applications in intralogistics by bridging the gap between theoretical models and real-world constraints.}, language = {en} } @inproceedings{GalkaWappler, author = {Galka, Stefan and Wappler, Mona}, title = {INTEGRATION OF CASH FLOW MANAGEMENT AND FURTHER ASPECTS OF THE SUPPLY CHAIN MANAGEMENT IN PRODUCTION SYSTEM DESIGN}, series = {IFAC-PapersOnLine}, volume = {56}, booktitle = {IFAC-PapersOnLine}, number = {2}, publisher = {International Federation of Automatic Control. Published by Elsevier Ltd.}, address = {Yokohama}, issn = {2405-8963}, doi = {10.1016/j.ifacol.2023.10.1687}, pages = {947 -- 952}, abstract = {One major goal of production system design is to decide on space requirements in the plant. In this phase, detailed information about the supply chain network (e.g. which suppliers deliver which parts) is often unavailable. Nevertheless, typical decisions in supply chain management, like the definition of replenishment processes and quantities or make-or-buy decisions, impact space requirements and the capital investment in raw materials and should therefore be considered in factory and production planning. This research article proposes a simulation approach for a production simulation in which raw material replenishment is integrated to evaluate the capital investment and space requirements for raw materials.}, subject = {Supply chain management}, language = {de} } @techreport{SchuheggerGalka, author = {Schuhegger, Lukas and Galka, Stefan}, title = {Herausforderungen von produzierenden Startups}, doi = {10.35096/othr/pub-8852}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-88520}, pages = {30}, abstract = {Startups bringen mit ihrer Dynamik und neuen innovativen Gesch{\"a}ftsmodellen frischen Wind in die deutsche Unternehmenslandschaft. Die disruptiven Ans{\"a}tze gestalten die Zukunft und damit geraten sie immer weiter in den Fokus, unter anderem auch f{\"u}r Investoren. Das Ziel der Studie ist es, Zusammenh{\"a}nge zwischen Herausforderungen und Eigenschaften von produzierenden Startups darzulegen. Dieses Wissen soll an andere Startups weitergegeben werden, um die Erfolgschancen in der Gr{\"u}nderszene zu erh{\"o}hen. Im Juli 2021 wurde hierzu eine Umfrage entworfen, um die Erfahrungen von Gr{\"u}ndern und Startup-Mitarbeitern zu sammeln und die spezifischen Herausforderungen besser zu verstehen.}, subject = {Unternehmensgr{\"u}ndung}, language = {de} } @inproceedings{GalkaStrassburgerLangetal., author = {Galka, Stefan and Strassburger, Steffen and Lang, Sebastian and Reggelin, Tobias}, title = {Introduction to the Minitrack on Simulation Modeling and Digital Twins for Decision Making in the Age of Industry 4.0}, series = {Proceedings of the 57th Hawaii International Conference on System Sciences (HICSS), January3-6, 2024, Honolulu, Hawaii}, booktitle = {Proceedings of the 57th Hawaii International Conference on System Sciences (HICSS), January3-6, 2024, Honolulu, Hawaii}, editor = {Bui, Tung}, publisher = {ScholarSpace}, isbn = {978-0-9981331-7-1}, doi = {10.24251/HICSS.2024.206}, pages = {1647 -- 1648}, abstract = {The minitrack contains contributions with a focus on simulation modeling and digital twins and decision making in the context of Industry 4.0. The use of simulation models and digital twins is manifold, from planning to virtual commission and real-time operational decision support. Cyber-physical systems integrate the real world and the virtual world to enable decision making in the age of Industry 4.0. For example, customer decisions and supply disruptions which directly influence manufacturing and logistics systems require immediate decisions. Thus, models must have the capability to support decision making in manufacturing as well as in internal and external logistics in real-time. Methods include discrete-event simulation, discrete-rate simulation, hybrid simulation, system dynamics simulation, the combination of simulation modeling with machine learning or optimization heuristics, prescriptive analytics, and adaptive systems. Furthermore, this minitrack addresses simulation education and simulation models used for education and training in manufacturing and logistics.}, language = {en} } @article{WeigertGalkaDuennweberetal., author = {Weigert, Alexander and Galka, Stefan and D{\"u}nnweber, Jan and Meißner, Sebastian and Riege, Jacob and B{\"o}ck, Hendrik and Wagner, Martin}, title = {Simulationsframework mit Anordnungsalgorithmus von Petri-Netzen}, series = {Zeitschrift f{\"u}r wirtschaftlichen Fabrikbetrieb}, volume = {121}, journal = {Zeitschrift f{\"u}r wirtschaftlichen Fabrikbetrieb}, number = {3}, publisher = {DeGruyter}, doi = {10.1515/zwf-2026-1035}, pages = {125 -- 130}, abstract = {Die serienm{\"a}ßige Produktion von Elektrolysezellen befindet sich im Anfangsstadium, sodass belastbare Erfahrungen f{\"u}r standardisierte Produktionssysteme fehlen. Die Planung ist daher durch hohe Unsicherheit gepr{\"a}gt. Unterschiedliche Gestaltungsm{\"o}glichkeiten der Produktionssysteme m{\"u}ssen fr{\"u}hzeitig bewertet und ihre Leistungsf{\"a}higkeit mit dynamischen Methoden, wie der Simulation, abgesichert werden. Anhand eines von den Autoren entwickelten Simulationsframeworks mit automatisierter Modellgenerierung auf Basis der Petri-Netz-Logik zeigt dieser Beitrag die M{\"o}glichkeit der Simulation von Produktionssystemen in der Planung. Ein besonderes Leistungsmerkmal des Frameworks ist, dass zun{\"a}chst un{\"u}bersichtlich generierte Modelle mit einem Graphenalgorithmus so angeordnet werden, dass ihre Funktionsweise aus der Darstellung nachvollziehbar wird.}, language = {de} }