Publikationen


7032 Publikationen gefunden
    NachhaltigF: Angewandte Naturwissenschaften und WirtschaftsingenieurwesenS: IPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Michael Benisch, O. Fähnle, Rolf Rascher

    Application of a pressure measuring film for pressure observation in overarm polishing

    Proceedings of EOSAM 2020 (European Optical Society Biennial Meeting; 7-11 September 2020; online), vol. 238

    2020

    DOI: 10.1051/epjconf/202023803003

    Abstract anzeigen

    In previous publications the inhomogeneous pressure transfer through the polishing tool onto a glass surface could be shown. This experiment shows polishing trials with different polishing materials and the differences in the homogeneity of the pressure transfer through them. Only the properties of the material will be discussed explicitly, the change of the tool constitution through the process will be part of further publications.

    DigitalNachhaltigF: Angewandte Naturwissenschaften und WirtschaftsingenieurwesenS: IPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Simon Killinger, Johannes Liebl, Rolf Rascher

    Interferometric measurement with robot kinematics

    Proceedings of SPIE Optical Engineering + Applications (24 August - 04 September, 20208; Optical Manufacturing and Testing XIII; online conference), San Diego, United States, vol. 11487

    2020

    DOI: 10.1117/12.2568348

    Abstract anzeigen

    Polishing precision optics is highly depending on the operator. Hence, a good result relies on a skilled optician who controls the process chain. This process chain consists of different manual steps such as loading, cleaning and calibrating different machines. To get more control over the process and to speed up the production we currently build an operator independent polishing cell using a single robot. Therefore, we positioned the robot in the middle of the production cell, which enables the robot to reach and manipulate different tools located around the kinematic. One major issues is the lower positioning accuracy and stiffness of an industrial robot in comparison to standard optic machines. Probably the most challenging step concerning accuracy in precision optics manufacturing is the interferometric measurement. In this paper, we present a method using an ESDI Intellium H2000 interferometer, designed for use in unsteady conditions. The robot positions the surface under test without the use of any additional mechanics to enhance the accuracy. The measurement position was manually teached in and approached several times for a statistically significant evaluation. The results show that the robot is sufficiently accurate and stable to perform interferometric measurements. This is a key element towards a completely operator-independent manufacturing cell for precision optics.

    NachhaltigF: Europan Campus Rottal-InnS: TC Freyung

    Zeitschriftenartikel

    Javier Valdés, Sebastian Wöllmann, Andreas Weber, G. Klaus, Christina Sigl, M. Prem, Robert Bauer, Roland Zink

    A framework for regional smart energy planning using volunteered geographic information

    Advances in Geosciences, vol. 54, no. 10 December 2020, pp. 179-193

    2020

    DOI: 10.5194/adgeo-54-179-2020

    Abstract anzeigen

    This study presents a framework for regional smart energy planning for the optimal location and sizing of small hybrid systems. By using an optimization model – in combination with weather data – various local energy systems are simulated using the Calliope and PyPSA energy system simulation tools. The optimization and simulation models are fed with GIS data from different volunteered geographic information projects, including OpenStreetMap. These allow automatic allocation of specific demand profiles to diverse OpenStreetMap building categories. Moreover, based on the characteristics of the OpenStreetMap data, a set of possible distributed energy resources, including renewables and fossil-fueled generators, is defined for each building category. The optimization model can be applied for a set of scenarios based on different assumptions on electricity prices and technologies. Moreover, to assess the impact of the scenarios on the current distribution infrastructure, a simulation model of the low- and medium-voltage network is conducted. Finally, to facilitate their dissemination, the results of the simulation are stored in a PostgreSQL database, before they are delivered by a RESTful Laravel Server and displayed in an angular web application.

    DigitalS: TC Grafenau

    Beitrag (Sammelband oder Tagungsband)

    Lisa-Marie Hanninger, Jessica Laxa, Diane Ahrens

    Rural Areas on Their Way to a Smart Village - Experiences from Living Labs in Bavaria

    Proceedings of the 33rd BLED eConference "Enabling Technology for a Sustainable Society", Maribor, vol. 33

    2020

    DigitalF: Elektrotechnik und MedientechnikS: TSZ Weißenburg

    Beitrag (Sammelband oder Tagungsband)

    Alireza Tajafari Sahebi, Amir Samiee, László Juhász

    MRAC Implementation for Electric Throttle Valve

    Proceedings of the 2020 10th International Conference on Advanced Computer Information Technologies (ACIT) [September 6-8, 2020; Deggendorf]

    2020

    DOI: 10.1109/ACIT49673.2020.9208929

    Abstract anzeigen

    Design, implementation and testing of a model reference adaptive controller for an electric throttle valve are presented. An important step by design an adaptive controller is to find an adaptation mechanism. For this purpose, we employed the Lyapunov stability theory. The main challenge in this project originates from a certain term in the updating rules. This term contains the angular velocity, which is not measurable directly. Numerical differentiation of the measured angular position yields a noisy signal. To overcome this problem, we used a non-ideal derivative method. The use of a non-linear state observer based on extended Kalman filter could significantly enhance the control quality. This task is currently in progress.

    F: Elektrotechnik und Medientechnik

    Beitrag (Sammelband oder Tagungsband)

    Günter Keller

    Electromagnetic Compatibility of Switched-Mode Power Supplies

    IEEE International Conference on Industrial Technology (ICIT 2020)

    2020

    DigitalF: Maschinenbau und MechatronikI: Fraunhofer AWZ CTMT

    Zeitschriftenartikel

    Jochen Hiller

    Computertomographie (CT) senkt Kosten bei der Retourenbearbeitung

    Sensorik-Magazin des Clusters Sensorik Strategische Partnerschaft Sensorik e.V., vol. 99, no. 4, pp. 3-5

    2020

    DigitalF: Maschinenbau und MechatronikI: Fraunhofer AWZ CTMT

    Zeitschriftenartikel

    F. Heilmeier, R. Koos, M. Singer, C. Bauer, Peter Hornberger, Jochen Hiller, W. Volk

    Evaluation of Strain Transition Properties between Cast-In Fibre Bragg Gratings and Cast Aluminium during Uniaxial Straining

    Sensors, vol. 20, no. 21

    2020

    DOI: 10.3390/s20216276

    Abstract anzeigen

    Current testing methods are capable of measuring strain near the surface on structural parts, for example by using strain gauges. However, stress peaks often occur within the material and can only be approximated. An alternative strain measurement incorporates fibre-optical strain sensors (Fiber Bragg Gratings, FBG) which are able to determine strains within the material. The principle has already been verified by using embedded FBGs in tensile specimens. The transition area between fibre and aluminium, however, is not yet properly investigated. Therefore, strains in tensile specimens containing FBGs were measured by neutron diffraction in gauge volumes of two different sizes around the Bragg grating. As a result, it is possible to identify and decouple elastic and plastic strains affecting the FBGs and to transfer the findings into a fully descriptive FE-model of the strain transition area.We thus accomplished closing the gap between the external load and internal straining obtained from cast-in FBG and generating valuable information about the mechanisms within the strain transition area.It was found that the porosity within the casting has a significant impact on the stiffness of the tensile specimen, the generation of excess microscopic tensions and thus the formation of permanent plastic strains, which are well recognized by the FBG. The knowledge that FBG as internal strain sensors function just as well as common external strain sensors will now allow for the application of FBG in actual structural parts and measurements under real load conditions. In the future, applications for long-term monitoring of cast parts will also be enabled and are currently under development.

    DigitalF: Maschinenbau und MechatronikI: Fraunhofer AWZ CTMT

    Zeitschriftenartikel

    Jochen Hiller, Peter Landstorfer, Philipp Marx, Matthias Herbst

    Evaluation of the impact of faulty scanning trajectories in robot-based x-ray computed tomography

    Measurement Science and Technology, vol. 32, no. 1

    2020

    DOI: 10.1088/1361-6501/abaf2a

    Abstract anzeigen

    X-ray computed tomography (CT) imaging for industrial applications is limited to certain physical conditions to be fulfilled. The size of the measuring object and the accumulated wall thickness are two fundamental conditions. An omission of these conditions by not capturing object attenuation information by the x-ray detector leads to missing data in the 3D reconstruction process and results as a consequence in image degradation and artifacts. Conventional industrial x-ray CT is based on cone-beam projections and circular or helical scanning trajectories using linear axis and a rotary (lift) table. For many inspection tasks on big-sized or unusually shaped objects the physical limits for obtaining a sufficient high image quality are reached very quickly when using conventional CT systems. Industrial six-axis robots offer much more flexibility with respect to the conditions mentioned earlier and can overcome the limitations of conventional scanners. In the present work we characterized an industrial six-axis robot in its working space following ISO 9283 in terms of pose accuracy and pose repeatability. These results are then used to simulate faulty scanning trajectories in terms of pose deviations where a single robot is used as an object manipulator to rotate virtual specimens on a circular trajectory resulting in different (faulty) reconstruction datasets. These datasets are evaluated visually and by using performance parameters and geometrical features in order to determine the reproduction fidelity (performance) of a one arm robot-based CT system depending on different pose errors. With the results obtained it was shown that a robot-based CT system of type B (in our classification scheme) using one robot as object manipulator should be able to reach a spatial resolution power in the range of the voxel size (in our case 200 µm) and smaller (neglecting effects from focal spot size, detector unsharpness from x-ray to light conversation and scatter radiation) if systematic pose errors are compensated using appropriate calibration methods.

    DigitalF: Maschinenbau und MechatronikI: Fraunhofer AWZ CTMT

    Zeitschriftenartikel

    S. Zabler, M. Maisl, Peter Hornberger, Jochen Hiller, C. Fella, R. Hanke

    X-ray imaging and computed tomography for engineering applications

    tm - Technisches Messen, vol. 87, no. Online veröffentlicht: 08.04.2020

    2020

    DOI: 10.1515/teme-2019-0151

    Abstract anzeigen

    After an incremental development which took place over four decades, X-ray imaging has become an important tool for non-destructive testing and evaluation. Computed Tomography (CT) in particular beholds the power of determining the location of flaws and inclusions (e. g. in castings and composites) in three-dimensional object coordinates. Therefore, and thanks to a speed-up of the measurement, CT is now routinely considered for in-line inspection of electronics, castings and composites. When precision and not speed is important, Micro-CT (μCT) can be employed for Dimensional Measurements (DM, e. g. quality assurance and shape verification), as well as for in situ testing, and for characterizing micro-structures in metals and composites. Using appropriate image processing and analysis μCT can determine the local fibre orientation in composites, the granular morphology of battery cathodes or the inter-connectivity of certain phases in casting alloys. Today, the large variety of X-ray instruments and methods poses an application problem which requires experience and a lot of knowledge for deciding which technique applies best to the task at hand. Application-specific guidelines exist for X-ray radiography testing (RT) only, whereas standardization has been applied to CT, unfortunately leaving out high resolution subμ CT, and nano-CT. For the latter exist an equally high number of NDT applications, however these instruments still necessitate a profound expertise. The task is to identify key industrial applications and push CT from system standardization to application specific automation.

    DigitalS: TC Grafenau

    Zeitschriftenartikel

    Ali Fallah-Tehrani

    The Choquet Kernel on the use of Regression Problem

    Information Sciences, no. 08 December 2020

    2020

    DOI: 10.1016/j.ins.2020.11.051

    Abstract anzeigen

    Recently, we have presented a new family of kernels on the basis of the discrete Choquet integral. While a naïve computation of this kernel has an exponential complexity in the number of features, we have proposed an efficient approach with computational complexity of 1. This kernel family is able to recognize dependencies between features and moreover it can be regularized through a proper selection of q-additivity. In fact, to reduce the effect of over-fitting there is an opportunity to restrict the flexibility of kernel to a lower degree. A key feature of the Choquet integral in a data-driven way is its monotonicity, however, this representation does not consider any monotonicity constraint; hence it is versatile for other applications, too. This issue is highlighted in the experimental study. In this regard, we apply the Choquet kernel for regression task and compare the performance of the proposed kernel versus state-of-the-art support kernel-based regression methods as well as random forest.

    DigitalMobilS: TC Freyung

    Beitrag (Sammelband oder Tagungsband)

    M. Novàk, J. Geyer, M. Prokýšek, M. Hais, S. Gril, M. Davidková, P. Doležal, Peter Hofmann, Rajan Paudyal

    Construction of a Multisensor UAV System for Early Detection of Forest Pests

    Advances in Intelligent Systems and Computing V, Cham, Switzerland, vol. 1293

    2020

    ISBN: 978-3-030-63270-0

    DigitalNachhaltigF: Europan Campus Rottal-Inn

    Zeitschriftenartikel

    Kueppers. M., C. Perau, M. Franken, H. Heger, Matthias Huber, M. Metzger, S. Niessen

    Data-Driven Regionalization of Decarbonized Energy Systems for Reflecting Their Changing Topologies in Planning and Optimization

    Energies, vol. 13, no. 16

    2020

    DOI: 10.3390/en13164076

    Abstract anzeigen

    The decarbonization of energy systems has led to a fundamental change in their topology since generation is shifted to locations with favorable renewable conditions. In planning, this change is reflected by applying optimization models to regions within a country to optimize the distribution of generation units and to evaluate the resulting impact on the grid topology. This paper proposes a globally applicable framework to find a suitable regionalization for energy system models with a data-driven approach. Based on a global, spatially resolved database of demand, generation, and renewable profiles, hierarchical clustering with fine-tuning is performed. This regionalization approach is applied by modeling the resulting regions in an optimization model including a synthesized grid. In an exemplary case study, South Africa’s energy system is examined. The results show that the data-driven regionalization is beneficial compared to the common approach of using political regions. Furthermore, the results of a modeled 80% decarbonization until 2045 demonstrate that the integration of renewable energy sources fundamentally changes the role of regions within South Africa’s energy system. Thereby, the electricity exchange between regions is also impacted, leading to a different grid topology. Using clustered regions improves the understanding and analysis of regional transformations in the decarbonization process.

    NachhaltigF: Angewandte Naturwissenschaften und WirtschaftsingenieurwesenS: IPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Christian J. Trum, M. Jung, Beate Schmidbauer, Sebastian Sitzberger, E. Willenborg, Rolf Rascher

    Hybrid-process-chain for polishing optical glass lenses – HyoptO

    Proceedings of SPIE Optical Engineering + Applications (24 August - 04 September, 20208; Optical Manufacturing and Testing XIII; online conference), San Diego, United States, vol. 11487

    2020

    DOI: 10.1117/12.2568400

    Abstract anzeigen

    A number of process steps that build on one another are required to manufacture optical components from glass. The polishing steps are the most time-consuming and therefore cost-intensive parts of the process chain. Low removal rates and the depth of the Sub Surface Damage (SSD) to be removed contribute to this. An alternative for the complete removal of the SSD-penetrated material using contactless polishing methods such as Ion Beam Figuring (IBF) is the healing of the SSD. Due to the induced energy during laser-polishing, the material is remelted at the defects and the SSD are closed. However, laser-polishing is also associated with disadvantages in terms of shape accuracy and surface quality. The project HyoptO is therefore devoted to the development of a hybrid-process-chain consisting of laser processing and conventional polishing. It is expected that the healing times of the SSD can significantly reduce the process times in the subsequent polishing steps. However, there are a few questions to be answered regarding the economic use of the hybrid-process-chain. These include:

    DigitalS: TC Freyung

    Beitrag (Sammelband oder Tagungsband)

    M. K. Vichrová, P. Hájek, M. Kepka, Laura Fiegler, Mariann Juha, Wolfgang Dorner, R. Fiala

    Current Digital Travel Guide of Peregrinus Silva Bohemica Project

    Proceedings of the 2020 10th International Conference on Advanced Computer Information Technologies (ACIT) [September 6-8, 2020; Deggendorf]

    2020

    DOI: 10.1109/ACIT49673.2020.9208922

    Abstract anzeigen

    Delivering a piece of proper and interesting information to tourists is always a challenge to deal with. It can be provided by many possible ways using traditional analogue materials (flyers, information table or paper maps) or using modern technologies such as web pages, mobile applications or an online multimedia tourist guide. One of online tourist guides is a travel guide created in Peregrinus Silva Bohemica project. This paper provides information about the final stage of such a guide from content and a technical point of view, to point out the complexity and usefulness of such a tool for tourists.

    DigitalS: TC Freyung

    Beitrag (Sammelband oder Tagungsband)

    M. Novàk, M. Prokýšek, P. Doležal, M. Hais, S. Gril, M. Davídková, J. Geyer, Peter Hofmann, Rajan Paudyal

    Multisensor UAV System for the Forest Monitoring

    Proceedings of the 2020 10th International Conference on Advanced Computer Information Technologies (ACIT) [September 6-8, 2020; Deggendorf]

    2020

    DOI: 10.1109/ACIT49673.2020.9208993

    Abstract anzeigen

    In recent years, unmanned aerial vehicles (UAV) of various shapes, sizes and functions have been increasingly used for civilian applications in a wide range of fields. UAVs are flexible, inexpensive, with the ability to carry high resolution sensing systems. UAVs fill the gap between manned aircraft and satellite remote sensing systems. When searching for new methodologies, especially in forestry research, UAVs are a unique platform. Remote forest sensing, forest mapping, forest precise measurement, forest fire monitoring and support for intensive forest management are areas in which remote sensing is fully utilized. The advantages of remote sensing are mainly low material and operating costs, flexible space and time deployment, and high intensity data collection. In order to move remote sensing applications from the experimental phase into real deployment, it is necessary to come up with new methodologies that can be determined using UAVs.

    DigitalGesundF: Angewandte GesundheitswissenschaftenS: TC Freyung

    Beitrag (Sammelband oder Tagungsband)

    Ludwig Schiller, Manuela Wühr, Rainer Pöschl, Wolfgang Dorner

    Concept for the Large Scale Deployment of Ambient Assisted Living Systems

    Proceedings of the 2020 10th International Conference on Advanced Computer Information Technologies (ACIT) [September 6-8, 2020; Deggendorf]

    2020

    DOI: 10.1109/ACIT49673.2020.9208911

    Abstract anzeigen

    This paper deals with the problem of equipping 100 households in Lower Bavarian with sensors using different interfaces and protocols. This sensor set in the households is used in the context of the research project DeinHaus 4.0 of Deggendorf Institute of Technology. This project focuses on supporting technologies to enable elderly people to live as long as possible in their own house or apartment. Therefore, a set of sensors and Ambient Assisted Living (AAL) technologies are used to build a supporting system. Furthermore, the system collects, anonymizes and stores the sensor data for further technical and social analysis.

    NachhaltigF: Europan Campus Rottal-Inn

    Beitrag (Sammelband oder Tagungsband)

    A. Schmeisky, Janina Beduhn

    The K+S brine challenge: Approach to create sustainable solutions

    Global Goals Yearbook 2020, vol. 2020

    2020

    ISBN: 9783946284093

    DigitalF: Angewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    Heribert Popp, Monica I. Ciolacu, Leon Binder

    Education 4.0: IoT- und CoP-unterstützte Smarte E-Learning Prozesse

    Tagungsband zum 19. E-Learning-Tag der FH JOANNEUM: Innovation & Reflexion – Henne oder Ei? , vol. 130

    2020

    Abstract anzeigen

    Studierende erleben im Lernmanagementsystem (LMS) „Moodle“ smarte E-Learning Prozesse in Mathematik- und Wissensmanagement-Kursen. „Smartes E-Learning“ besteht in Anlehnung an „smarte Produkte“ aus einer physischen, einer intelligenten und einer Vernetzungs-Komponente. Vernetzt sind die StudentInnen mit dem LMS einerseits in „Communities of Practice“ (CoP) zur Reflexion und andererseits über die Sensoren ihrer Smartphones oder Smartwatches (physische Komponente). Damit lässt sich dieses Lernumfeld der Kategorie “Internet of Things” (IoT) zuordnen. Im Lernprozess können die eingebetteten Sensoren mit den Biosignalen „Puls“ (HR) und „Herzfrequenzvariabilität“ (HRV) zur Selbstreflexion der Lernenden, zur Steuerung des Lernsystems und zur Personalisierung des Nutzungserlebnisses dienen. Erste Tests fanden u.a. Korrelationen zwischen erreichten Punkten in den Kontrollfragen und den Werten der Biosignale. Als intelligente Komponenten sind BenutzerInnenmodellierung, Chatbot, maschinelles Lernen usw. bei „Education 4.0“ im Einsatz.