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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Model-Integrated Engineering of Smart Energy Distribution Systems

Galkin, Nikolai January 2023 (has links)
Model-Based Systems Engineering (MBSE) is a formal method that is used to support analysis, design, independent verification, and validation inherent in the development of software and hardware systems. MBSE applications are present in many areas of our daily lives, including manufacturing, robotics, healthcare, automation, etc. However, despite their rapid and sustainable growth during the last few years, the MBSE methods themselves are quite far away from perfect. There are some current problems, which resist more rapid penetration of MBSE systems in their development. One of them is that currently the majority of MBSE systems are vendor dependent and, as a result, they have poor compatibility with each other. Furthermore, currently, there is a gap between the design of a digital model and a control model of an engineering system. Currently, this problem is usually solved by involving two or more groups of engineers, where each of these groups works on their own problems. All this costs companies additional engineering time and, as a result, development costs. Therefore new, and more sophisticated approaches for the generation of MBSEs are needed in order to overwhelm the challenges highlighted above. In order to narrow the field of study and better concentrate on specific problems, smart power distribution systems have been chosen as the main research object for this dissertation. Thus, in this work, the author introduces Model-Integrated Systems Engineering (MISE), as the MBSE sub-discipline. Here and later in this paper, the author will refer to MISE as the main area of interest. Also, the author uses the term DigitalTwin to refer to the multilayered structure of a complex distributed automation system consisting of three layers, namely:– the static machine-readable information about the infrastructure of the smart energy system,– the simulation model layer,– the distributed control layer for the investigated smart energy system. In general, two new transformation approaches for automatic MISE generation are discussed in the scope of this dissertation, namely:1. Transformation of the System Configuration Design (SCD) files of an electric system(presented in IEC 61850) into the corresponding SIMULINK model.2. Transformation of specification files of electronic components into corresponding OPC UA information model.All discussed approaches are implemented in the form of a program code that is publicly available on the Internet. The IEC 61850 and OPC UA standards are considered key components of the current dissertation. IEC 61850 is an international standard covering different sides of smart energy distribution systems including communication protocols for diverse equipment in a substation, including protection, control, and measurement equipment, as well as intelligent electronic devices (IEDs). Information Modeling OPC UA is a platform-independent service-oriented architecture that combines the concepts of semantic modeling. First, the structure of the IEC 61850 standard is discussed, as well as its potential benefits for the MISE of smart power distribution systems in terms of the automatic transformation of the information model. Next, the architecture of the electrical system (the SCD file) of the electrical vehicle (EV) charging station (CS) is proposed as an example. The aim is to design a mechanism for the automatic transformation of MISE in two domains, namely:- Physical model of the electrical system itself,- Automatically build a communication channel between the digital replica (the model) of the electrical system and the virtual energy management system (EMS). Thus, this work aims to contribute to the design and virtual commissioning of Digital Twin systems, as well as to improve the interoperability between IEC 61850 compliant systems and electric vehicle charging stations (paper C explains that in more detail). Finally, by narrowing down the scope of the investigation to one specific electrical device, a new approach for converting integrated circuit (IC) specification files of an electric system into an OPC UA information model is discussed. The designed transformation algorithm is based on the directed graphs theory (paper D explains that in more detail). The purpose of this work is to highlight and contribute to the problems of the MISE analysis solutions.  In summary, the work presented in this dissertation raises questions about interoperability between different standards, the problems of converting the IEC 61850 information model into MISE, verification of the generated MISE compared to the original IEC 61850 information model, and the problems of forming an information model OPC UA.
92

EVALUATING CRYSTAL FRAMEWORK IN PRACTICE

Mertala, Victor, Christopher, Nordin January 2024 (has links)
Cyber-physical systems (CPSs) are used in several industries, such as healthcare, automotive, manufacturing, and more. The fact that CPSs often contain components integrated via communication networks means that malicious actors can exploit vulnerabilities in these components through cyber attacks. CRYSTAL Framework has been shown in previous research to be able to detect cyber attacks on CPSs. However, this has only been proven in simulation. Our research builds upon these previous research as we aim to prove that CRYSTAL Framework is a viable method for monitoring real systems to detect abnormal behaviours.  The Tiny Twin is an abstract behavioral model that defines normal running behaviour of a system, which can then be used by to compare the current state of a monitored system to detect possible attacks and abnormal behaviours. We built a monitor that integrates such a Tiny Twin, working by passively listening on input and output of components in a monitored system. We designed and implemented two different scenarios, a security alarm system and a temperature control system (TCS), to test the CRYSTAL Framework. In testing both implemented scenarios our monitor successfully detected all but one attacks during runtime by comparing the system's current state with the expected state as defined in the Tiny Twin.
93

Real Time Monitoring of Machining Process and Data Gathering for Digital Twin Optimization

Rajendran, Ajith, Asokan, Gautham January 2021 (has links)
In the development stages of a Digital twin of production assets, especially machine tools, real time process monitoring and data gathering proves to be vital. Having a monitoring system that monitors and updates the operators or managers in real time, helps improve productivity in terms of reducing downtime through predictive/preventive analytics and by incorporating in process quality assessment capabilities. When it comes to Real time monitoring of machine tools andprocesses, sensor technologies have proven to be the most effective and widely researched. Years of research and development have paved the way for many smart sensor technologies that come both in built with the machine tools as well as external applications. However, these technologies prove to be expensive and complicated to implement especially for Small and Medium Enterprises. This thesis focuses on evaluating and testing a simple, cost-efficient monitoring system using inexpensive sensor technologies that would help optimize an existing Digital twin setup for machine tools for Small and Medium Enterprises. Experiments with a 5 axis CNC machine tool using different tools and varying operating parameters, materials were performed,and the relevant sensor data were collected, mapped, analysed for accuracy and benchmarking. The thesis also evaluates the integration of this data with the information already collected from other sources, improve existing data reliability, and provides guidelines on this could be transformed usefully to create more value to SME’s.
94

Digital Twin Performance : Unity as a platform for visualizing interactive digital twins

Nämerforslund, Tim January 2022 (has links)
The project set out to construct a proof of concept for surface deformation in the Unity Engine using available assets and tools compatible with the Unity Engine, and via the proof of concept investigate which factors in a mesh deformation simulation that affects performance in terms of frames per second, memory usage and usability the most. This while looking into suitable data structures in the Unity Engine for handling expected data in a physics simulation of a surface deformation, such that of mining or scraping a cave wall. The project aims to answer these questions via testing and trail and error, performing tests while recording data which is plotted and discussed. To save time and start testing faster the usage of a premium assets called Digger Pro is used, allowing for quick set up of mesh manipulation inf both editor and play mode. Testing shows that one of the major factor for performance degradation is mesh resolu-tion, as it directly contributes to an increase in data points that needs to be kept track of and calculated. The Unity Engine and Digger PRO man-ages fairly well to stay above the targeted 30 frames per second limit even with medium level settings for meshes, all while maintaining acceptable memory usage levels. All this ties into the idea of an increased usage of digital twins in many different scenarios, and therefore the scientific community’s view on digital twins main challenges are summarized and discussed, hoping to shed further light on the current status of digital twin technology.
95

Haptic-Enabled Robotic Arms to Achieve Handshakes in the Metaverse

Mohd Faisal, 26 September 2022 (has links)
Humans are social by nature, and the physical distancing due to COVID has converted many of our daily interactions into virtual ones. Among the negative consequences of this, we find the lack of an element that is essential to humans' well-being, which is the physical touch. With more interactions shifting towards the digital world of the metaverse, we want to provide individuals with the means to include the physical touch in their interactions. We explore the Digital Twin technology's prospect to support in reducing the impact of this on humans. We provide a definition of the concept of Robo Twin and explain its role in mediating human interactions. Besides, we survey research works related to Digital Twin's physical representation with a focus on under-actuated Digital Twin's robotic arms. In this thesis, we first provide findings from the literature, to support researchers' decisions in the adoption and use of designs and implementations of Digital Twin's robotic arms, and to inform future research on current challenges and gaps in existing research works. Subsequently, we design and implement two right-handed under-actuated Digital Twin's robotic arms to mediate the physical interaction between two individuals by allowing them to perform a handshake while they are physically distanced. This experiment served as a proof of concept for our proposed idea of Robo Twin. The findings are very promising as our evaluation shows that the participants are highly interested in using our system to make a handshake with their loved ones when they are physically separated. With this Robo Twin Arm system, we also find a correlation between the handshake characteristics and gender and/or personality traits of the participants from the quantitative handshake data collected during the experiment. Moreover, it is a step towards the design and development of Digital Twin's under-actuated robotic arms and ways to enhance the overall user experience with such a system.
96

An Open Data Model for Emulation Models of Industrial Components

Birtic, Martin January 2018 (has links)
Emulation is a technology, historically mostly used for virtual commissioning of automated industrial systems, and operator training. Trends show that new areas for deployment are being investigated. One way to broaden the scope of emulation technology is to increase emulation detail level. The University of Skövde conduct research within emulation technology, and are developing a higher detail level emulation platform performing  on component level. For transparent and systematic development of component models on this level, an open, extensible, and flexible data model for emulation models of industrial components is wanted. This thesis is contributing to this endeavour by developing a first draft of such a data model. A demonstration is also conducted by implementing a few components into the developing emulation environment, using XML as file format. An iterative "design and creation" methodology was used to develop and implement an object oriented data model. A selected set of industrial components were used to develop and demonstrate the data model, and the final result is visually represented as a class diagram together with explanatory documentation. Using the methodology and data modelling strategy used in this thesis, systematic and transparent development of emulation models on component level is possible in an extensible and flexible manner. / Emulering är en teknologi som historiskt mestadels använts vid virtuel idrifttagning av industriella automatiserade system samt vid operatörsträning. Trender visar att nya användningsområden utforskas. Ett sätt att vidga användningsområdet för emulering är att öka dess detaljnivå. Högskolan i Skövde utför forskning inom emulering och utvecklar en emuleringsplattform med utökad detaljnivå, även kallad komponentnivån. För att kunna arbeta systematiskt med utvecklandet av emuleringsmodeller för denna nivå önskas en öppen, skalbar, och flexibel datamodell för emuleringsmodeller. Detta examensarbete bidrar till detta genom att utveckla ett första utkast av en sådan data modell. Datamodellen demonstreras genom implementation inom den utvecklandes emuleringsmiljön, med hjälp av filformatet XML. En iterativ "design and creation" metodologi användes för att utveckla och implementera datamodellen. Ett set av industriella komponenter användes i utvecklingen och implementationen av datamodellen. Projektets resultat presenteras som ett klassdiagram tillsammans med förklarande dokumentation. Används projektes metodologi och datamodellerings-strategi kan man med fördel arbeta transparant och systematiskt med utveckling av emuleringsmodeller för anginven nivå. / TWIN
97

A QoE Model for Digital Twin Systems in the Era of the Tactile Internet

Alja'Afreh, Mohammad 25 October 2021 (has links)
The idiom by Thomas Fuller fantasizes the fact that seeing is believing, but the feeling is the truth. This ideology has fired the vision and innovation of the Mulsemedia, multiple-sensorial media, and Internet of Skills (IoS) which enable the exchange of control, skills, and expertise anytime/everywhere across the Internet. With the emergence of the new generation of mobile network (5G), Tactile Internet, as well as the deployment of Industry 4.0 and Health 4.0, multimedia systems are moving towards immersed haptic enabled human-machine interaction systems such as the Digital Twin (DT). Specifically, Industry 4.0 will be using DT and robots on a large scale. This will increase human-machine and interaction to a great extent. There will be multimodal communications used to interact with digital twins and robots, specially haptics. Hence, tactile internet will replace the conventional internet today. In fact, a DT system can also be extended in Health 4.0 domain to act as a COVID-19 early warning system. Tracking a person’s temperature and other symptom data in real-time can signal if as well as when it’s time to see a doctor or take a COVID test. Link to a COVID tracing app, the digital twin might help get more information about the virus relative to the person itself. Since there are currently no well-recognized models to evaluate the performance of these systems, to address this research lacuna, we proposed a Quality-of-Experience (QoE) model for DT systems containing multi-levels of subjective, objective, and physiopsychological influencing factors. The model is itemized through a fully detailed taxonomy that deduces the perceived user’s emotional and physical states during and after consuming spatial, temporal, proximal, and abstracted multi-modality media between humans and machines. Further, the taxonomy was modelled using the best practice of machine learning methods to show how QoE for digital twin applications can be inferred and predicted from interactions and biosignals in this class of applications. Furthermore, the taxonomy was applied to two use cases. The first one addresses the objective quality optimization for transmission in a large scale immersed haptic virtual reality over the Internet while the second one aims to objectively infer an important DT QoE physiological aspect i.e, fatigue.
98

Robotická paletizace řízená z PLC / Robotic palletization controlled by PLC

Šefránek, Adam January 2020 (has links)
The master's thesis deals with a robotic palletizing controlled by PLC. The first part provides examples of palletizing machines. The second part shows how ABB robot is controlled by B&R Automation PLC. The third part introduces selected approaches for automated pallet pattern generation. The fourth part designs library that allows pallet patterns to be generated using B&R Automation PLC. Fifth part covers creation of virtual palleziting cell, which is used to test library for automated pallet pattern generation.
99

Virtuální dvojče pro testbed Průmyslu 4.0 / Virtual twin for testbed Industry 4.0

Husák, Michal January 2020 (has links)
The goal of my master‘s thesis is to create a digital twin of a testbed Barman. The Barman is a school model of autonomous mixed drinks production line that demonstrates the principles of Industry 4.0. In the theoretical part of the thesis, the choice of a suitable tool for virtualization is discussed. The Tecnomatix Process Simulate and the Mechatronic Concept Designer module integrated in the NX platform is compared. The practical part of the work is divided into two phases. The first phase was about looking for a way to integrate the robotic SCARA manipulator. The second phase was focused on the virtualization of the cell Shaker in the latter of the tools mentioned before. This work is designed as a guide for creating and verifying the concept of a digital twin.
100

Nvrh a vroba optick©ho 3D scanneru / Construction and production of 3D optical scanner

BÄhnek, David January 2020 (has links)
The diploma thesis is focused on an optical method for 3D scanning. There is selected photogrammetry for creating 3D models. In the practical part, a mechanism for automatic photo capture is designed and manufactured and 3D printed with using a digital camera, Arduino microcontroller and stepper motors. There are proposed two methods of capturing photographs with which digital twins of reference objects are created. The result of the work is a functional 3D scanner. The next are evaluated used methods as well as the production costs and the time required by the operator when creating a digital copy of the object is listed.

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