TY - CHAP A1 - Bünte, Tilman A1 - Rill, Georg A1 - Ruggaber, Julian A1 - Tobolář, Jakub ED - Orlova, Anna ED - Cole, David T1 - Modelling and Validation of the TMeasy Tyre Model for Extreme Parking Manoeuvres T2 - Advances in Dynamics of Vehicles on Roads and Tracks II, Proceedings of the 27th Symposium of the International Association of Vehicle System Dynamics (IAVSD 2021): August 17-19, 2021, Saint Petersburg, Russia N2 - The TMeasy is a tyre model suitable for vehicle handling analyses and enables easy parametrisation. Recently, a convenient interface to Modelica was implemented by DLR to support the TMeasy also for vehicle modelling in multi-physical domains. This paper focuses especially on the particular problem of reliable reproduction of the tyre’s bore torque which occurs during parking manoeuvres. It outlines the theory behind it, discusses the Modelica interface implementation, and presents the results of parameter identification which were achieved based on real experiments with DLR’s research platform ROboMObil. Y1 - 2022 SN - 978-3-031-07305-2 SN - 978-3-031-07304-5 U6 - https://doi.org/10.1007/978-3-031-07305-2_94 SP - 1015 EP - 1025 PB - Springer CY - Cham ER - TY - CHAP A1 - Rill, Georg T1 - A Three-Dimensional and Nonlinear Virtual Test Car T2 - ENOC 2022, book of abstracts, 10th European Nonlinear Dynamics Conference: July 17-22, 2022, Lyon, France N2 - Virtual testing procedures have become a standard in vehicle dynamics. The increasing complexity of driver assistance sys- tems demand for more and more virtual tests, which are supposed to produce reliable results even in the limit range. As a consequence, simplified vehicle models, like the classical bicycle model or 4-wheel vehicle models, have to be replaced by a fully three-dimensional and nonlinear vehicle model, which also encompasses the details of the suspension systems. This paper presents a passenger car model, where the chassis, the four knuckles, and the four wheels are described by rigid bodies, the suspension system is modeled by the generic design kinematics, and the TMeasy tire model provides the tire forces and torques in all driving situations. Y1 - 2022 UR - https://enoc2020.sciencesconf.org/data/ENOC2022_proceedings.pdf SP - 49 EP - 58 CY - Lyon ER - TY - CHAP A1 - Rill, Daniel A1 - Butz, Christiane A1 - Rill, Georg ED - Kecskeméthy, Andrés ED - Geu Flores, Francisco T1 - Dynamic Interaction of Heavy Duty Vehicles and Expansion Joints T2 - Multibody Dynamics 2019, Proceedings of the 9th ECCOMAS Thematic Conference on Multibody Dynamics N2 - The “Smart Bridge (Intelligente Brücke)” project cluster, initiated by the German Federal Highway Research Institute (Bundesanstalt für Straßenwesen, BASt) and the Federal Ministry of Transport and Digital Infrastructure (BMVI), focuses on “smart” monitoring devices that allow an efficient and economic maintenance management of bridge infrastructures. Among the participating projects, the one presented herein focuses on the development of a smart expansion joint, to assess the traffic parameters on site. This is achieved by measuring velocity and weight of crossing vehicles. In reference measurements, performed with a three-axle truck and a typical tractor semi-trailer combination with five axles in total, it was shown that the interaction between the vehicle and the expansion joint is highly dynamic and depends on several factors. To get more insight into this dynamic problem, a virtual test rig was set up. Although nearly all vehicle parameters had to be estimated, the simulation results conform very well with the measurements and are robust to vehicle parameter variations. In addition, they indicate a significant influence of the expansion joint dynamic to the peak values of the measured wheel loads, in particular on higher driving velocities. By compensating the relevant dynamic effects in the measurements, a “smart” data processing algorithm makes it possible to determine the actual vehicle weights in random traffic with reliability and appropriate accuracy. Y1 - 2020 SN - 978-3-030-23131-6 U6 - https://doi.org/10.1007/978-3-030-23132-3_56 VL - 53 SP - 471 EP - 478 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Rill, Georg A1 - Arrieta Castro, Abel ED - Klomp, Matthijs ED - Bruzelius, Fredrik ED - Nielsen, Jens ED - Hillemyr, Angela T1 - A Novel Approach for Parametrization of Suspension Kinematics T2 - Advances in Dynamics of Vehicles on Roads and Tracks: Proceedings of the 26th Symposium of the International Association of Vehicle System Dynamics (IAVSD 2019), August 12-16, 2019, Gothenburg, Sweden N2 - n the automotive industry, simulations are needed to analyse the dynamics of vehicles and also of its main components and subsystems, e.g. tires, brakes and suspension systems. These simulations are required for an early-stage development and in consequence, they must deliver realistic results. Suspension systems plays a key role in comfort and safety of road vehicles. They usually consist of rigid links and force elements that are arranged with a specific topology. In addition, some of their functionalities are to carry the weight of the car and the passengers, and maintain a correct wheel alignment. In simulations involving suspension systems, lookup-tables are frequently used. They are obtained from a Kinematic and Compliance (KnC) test and then standardized for a specific vehicle simulation software. Nonetheless, lookup-tables require a reasonable number of characteristic points. Additionally, derivatives, interpolation, and extrapolation are not necessarily smooth. This produces results that depend on the interpolation technique and may be inaccurate. In this paper, a novel method called “design kinematics” is proposed. This method can describe the kinematic properties of almost any type of suspension systems. Comparisons with an analytic calculation and a KnC measurement shown that the design kinematics is able to represent the kinematic and compliance properties of suspension systems extremely well and very efficiently. KW - design Kinematics KW - Kinematic and compliance test KW - Suspension systems Y1 - 2020 SN - 978-3-030-38076-2 U6 - https://doi.org/10.1007/978-3-030-38077-9_210 SP - 1848 EP - 1857 PB - Springer International Publishing CY - Cham ER - TY - JOUR A1 - Rill, Georg T1 - Sophisticated but quite simple contact calculation for handling tire models JF - Multibody system dynamics N2 - Handling tire models like Pacejka (Tire and Vehicle Dynamics, 3rd edn., Elsevier, Amsterdam, 2012) or TMeasy (Rill in Proc. of the XV Int. Symp. on Dynamic Problems of Mechanics, Buzios, RJ, Brazil, 2013) consider the contact patch as one coherent plane. As a consequence, the irregularities of a rough road profile must be approximated by an appropriate local road plane that serves as an effective road plane in order to calculate the geometric contact point and the corresponding contact velocities. The Pacejka/SWIFT tire model employs a road enveloping model that generates the effective height and slope by elliptical cams. TMeasy just uses four representative road points for that purpose. In addition, TMeasy replaces the geometric contact point by the static contact point and shifts it finally to the dynamic contact point that represents the point where the contact forces are applied. In doing so, a rather sophisticated but still simple contact calculation is possible. Simulations obtained with a virtual tire test rig and fully nonlinear three-dimensional multibody system models of a motor-scooter and a passenger car demonstrate the potential of this contact approach. KW - Dynamic contact point KW - Effective road plane KW - Geometric contact point KW - Static contact point KW - Tire road contact KW - TMeasy tire model KW - Vehicle modeling Y1 - 2019 U6 - https://doi.org/10.1007/s11044-018-9629-4 VL - 45 IS - 2 SP - 131 EP - 153 PB - Springer Nature ER - TY - CHAP A1 - Rill, Georg A1 - Arrieta Castro, Abel ED - Kecskeméthy, Andrés ED - Geu Flores, Francisco ED - Carrera, Eliodoro ED - Elias, Dante A. T1 - The Influence of Axle Kinematics on Vehicle Dynamics T2 - Interdisciplinary Applications of Kinematics. Proceedings of the Third International Conference (IAK) N2 - The automotive industry employs many different kinds of axle suspension systems at modern passenger cars. Important criteria are costs, space requirements, kinematic properties, and compliance attributes. This paper illustrates that in particular the kinematic properties of a suspension system have a significant influence on the dynamics of vehicles. As a consequence, the kinematics of a suspension system must be modeled very precisely and nonlinear. Typical kinematical features of a suspension system are discussed by analyzing the most common double wishbone axle suspension system. The influence of the axle kinematics on vehicle dynamics is finally demonstrated by simulation results generated with a fully nonlinear and three-dimensional multibody vehicle model. KW - Double wishbone suspension system KW - Multibody system KW - Suspension kinematics KW - vehicle dynamics Y1 - 2019 SN - 978-3-030-16422-5 U6 - https://doi.org/10.1007/978-3-030-16423-2_2 VL - 71 SP - 23 EP - 31 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Rill, Georg T1 - TMeasy 6.0-A handling tire model that incorporates the first two belt eigenmodes T2 - Proceedings of the XI International Conference on Structural Dynamics (EURODYN 2020): Athens, Greece, 23.11.2020 - 26.11.2020 N2 - TMeasy 6.0, an extension to the standard TMeasy tire model of version 5.3, takes the relevant first two rigid body eigenmodes of the belt into consideration. These modes represent the in plane longitudinal and rotational movements of the belt relative to the rim. The dynamics of the longitudinal force is of higher order then and reproduces the tire wheel vibrations, required for indirect tire-pressure monitoring systems (iTPMS), sufficiently well. A tailored implicit solver, which takes the stiff coupling between the longitudinal force and the belt motions into account, still provides real-time performance in addition. Simulation examples show that a rigid body vehicle model equipped with TMeasy 6.0 makes it possible to investigate second generation indirect tire-pressure monitoring systems. KW - TMeasy Tire Model KW - Tire Force Dynamics KW - Frequency Analysis KW - Real-time Simulation KW - Virtual Test Rig Y1 - 2020 U6 - https://doi.org/10.47964/1120.9054.18673 SP - 676 EP - 689 PB - EASD Procedia ER - TY - BOOK A1 - Rill, Georg A1 - Arrieta Castro, Abel T1 - Road Vehicle Dynamics N2 - Road Vehicle Dynamics: Fundamentals and Modeling with MATLAB®, Second Edition combines coverage of vehicle dynamics concepts with MATLAB v9.4 programming routines and results, along with examples and numerous chapter exercises. Improved and updated, the revised text offers new coverage of active safety systems, rear wheel steering, race car suspension systems, airsprings, four-wheel drive, mechatronics, and other topics. Based on the lead author's extensive lectures, classes, and research activities, this unique text provides readers with insights into the computer-based modeling of automobiles and other ground vehicles. Instructor resources, including problem solutions, are available from the publisher. KW - Fahrdynamik Y1 - 2020 SN - 9780429244476 U6 - https://doi.org/10.1201/9780429244476 PB - CRC Press CY - Boca Raton, Fla. ER - TY - CHAP A1 - Rill, Georg ED - Lugner, Peter T1 - Multibody Systems and Simulation Techniques T2 - Vehicle Dynamics of Modern Passenger Cars N2 - This part begins with an introduction to Multibody Systems (MBS). It presents the elements of MBS and discusses different modeling aspects. Then, different methods to generate the equations of motion are presented. Solvers for ordinary differential equations (ODE) as well as differential algebraic equations (DAE) are discussed. Finally, techniques for “online” and “offline” simulations including real-time applications are presented like necessary for car development. Special examples show the connection between simulation and test results. KW - Differential equations KW - Equations of motion KW - Multibody systems KW - Numerical solution KW - Vehicle models Y1 - 2019 SN - 978-3-319-79007-7 U6 - https://doi.org/10.1007/978-3-319-79008-4_6 SP - 309 EP - 375 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Arrieta Castro, Abel A1 - Rill, Georg A1 - Weber, Hans I. ED - Carvalho, João Carlos Mendes ED - Martins, Daniel ED - Simoni, Roberto ED - Simas, Henrique T1 - Development of a Robust Integrated Control System to Improve the Stability of Road Vehicles T2 - Multibody Mechatronic Systems N2 - Nowadays, new technologies are pushing the road vehicle limits further. Promising applications, e.g., self-driving cars, require a suitable control system that can maintain the vehicle’s stability in critical scenarios. In most of current cars, the control systems actuates independently, meaning there is not a coordination or data sharing between them. This approach can produce a conflict between these standalone controllers and thus, no improvements on the vehicle’s stability are achieved or even a worse scenario can be generated. In order to overcome these problems, an integrated approach is developed in this work. This integration, defined in this work as Integrated Control (IC), is done by an intelligence coordination of all standalone controllers inside the vehicle, i.e., Anti-Lock Braking System (ABS), Electronic Stability Program (ESP) and Four-Wheel Steering System (4WS). The ABS model was built using Fuzzy logic, for which only three rules were necessary to get a good performance. To design the ESP and the 4WS, the simple handling vehicle model was used as a reference behavior. The IC was designed using the hierarchical approach with two layers, i.e., the upper and lower layer. The upper one, observes the side slip angle and depends of its value the upper layer triggers the ESP or the 4WS. Finally, in order to prove the improvements of the IC system over the non-integrated approach, a full-size vehicle model was used to perform simulation in run-off-road and μ-split scenarios. KW - 4WS KW - ABS KW - ESP KW - Integrated control KW - Run-off-Road scenarios Y1 - 2018 SN - 978-3-319-67566-4 U6 - https://doi.org/10.1007/978-3-319-67567-1_48 VL - 54 SP - 506 EP - 516 PB - Springer CY - Cham ER - TY - CHAP A1 - Arrieta Castro, Abel A1 - Chaves, Rafael B. A1 - Rill, Georg A1 - Weber, Hans I. ED - Fleury, Agenor de T. ED - Rade, Domingos A. ED - Kurka, R. G. T1 - Use of Integrated Control to Enhance the Safety of Vehicles in Run-Off-Road Scenarios T2 - Proceedings of DINAME 2017 : Selected Papers of the XVII International Symposium on Dynamic Problems of Mechanics N2 - In this work, an integrated vehicle control system (IC) is tested in run-off-road scenarios. The integrated approach was employed in order to coordinate vehicle control systems, i.e. the Anti-Lock Brake System (ABS), Four-wheel Steering (4WS) and the Electronic Stability Program (ESP). To perform a run-off-road maneuver, a fuzzy virtual test driver was designed. By receiving the lateral position of an obstacle and the vehicle’s relative yaw angle, the virtual test driver is capable of following a reference trajectory. Furthermore, to test the performance of the standalone controllers, i.e. ABS, ESP and 4WS, individual maneuvers are performed using a multibody vehicle model. The vehicle without any coordination between the control systems is used as reference. For the simulation results, it is concluded that the IC improves the vehicle stability and maneuverability in comparison with the non-integrated approach. Y1 - 2019 SN - 978-3-319-91217-2 SN - 978-3-319-91216-5 U6 - https://doi.org/10.1007/978-3-319-91217-2_30 SN - 2195-4356 SP - 431 EP - 443 PB - Springer CY - Cham ET - 1. Auflage ER - TY - JOUR A1 - Rill, Georg T1 - Reducing the cornering resistance by torque vectoring (X International Conference on Structural Dynamics, EURODYN 2017) JF - Procedia Engineering N2 - Usually, torque vectoring is used to reduce a significant understeer behavior at high speed cornering. Thus, providing larger vehicles with a sportive touch. Even on typical front wheel driven cars torque vectoring control is available now. Torque vectoring is nearly a standard on electric driven vehicles. Complex control and optimization strategies are applied to improve the maneuverability in particular or to enhance the driving behavior and reduce the energy consumption in addition. This paper shows, that a quite simple strategy will enhance the maneuverability and simultaneously reduce the cornering resistance in sharp bends. At first, a case study with a fully non-linear and three-dimensional vehicle model is performed. It turned out that a full drive torque shift to the outer wheels improves the maneuverability and reduces the cornering resistance in addition. This results are verified by an optimization performed with a simpler four-wheeled handling model. Here, the front steering angles and the driving torques at each of the four wheels are considered as free parameters. Minimizing the cornering resistance by taking the equations of motion for the four-wheeled handling model as constraints will deliver an optimal set of parameters then. KW - Constrained Optimization KW - Cornering Resistance KW - Four-wheeled Handling Model KW - Three-dimensional Vehicle Model KW - Torque Vectoring Y1 - 2017 U6 - https://doi.org/10.1016/j.proeng.2017.09.393 VL - 199 SP - 3284 EP - 3289 PB - Elsevier ER - TY - CHAP A1 - Hackl, Andreas A1 - Hirschberg, W. A1 - Lex, C. A1 - Rill, Georg ED - Spiryagin, Maksym ED - Gordon, Timothy ED - Cole, Colin ED - McSweeney, Tim T1 - Tyre type dependent transient force behaviour by means of a maxwell model T2 - The Dynamics of Vehicles on Roads and Tracks : Proceedings of the 25th Symposium of the International Association of Vehicle System Dynamics (IAVSD 2017), Rockhampton, Queensland, Australia, 14-18 August 2017 N2 - The present papers deals with the usability of an extended Maxwell model to describe the tyre dynamics during transient driving manoeuvres. In the present article, the para-metrisation process of a dynamic tyre model is investigated in a first step, using measurement data of tyre forces from a flat trac tyre test bench, (IABG 2016). Two tyre types of dimensions 255/50 R19 and 175/55 R15 are used. The practical applicability is discussed, considering the measurement procedure and the parameter optimisation process. In a second step, the performance of the dynamic tyre model is validated using measurements of manoeuvres under higher dynamic excitation. As a last step, an outlook is given on further research planned in which the presented model and parametrisation are adapted to a larger frequency range. Y1 - 2018 SN - 1351057170 U6 - https://doi.org/10.1201/9781315265506 SP - 157 EP - 162 PB - CRC Press CY - London ER - TY - CHAP A1 - Rill, Georg ED - Fleury, Agenor de T. T1 - Real-Time capable Multibody Model of dual Truck Front Axles T2 - Proceedings of DINAME 2023 - Selected Papers of the XIX International Symposium on Dynamic Problems of Mechanics, 26 Feb - 03 Mar 2023, Pirenópolis, Brazil N2 - Dual front steering axles are quite common in multi-axled heavy duty trucks. In standard layouts of such axle combinations, the steer motions of the wheels depend not only on the rotation of the steering wheel but also on the movements of the axles. As a consequence, the model complexity of the steering system should match with the complexity of the suspension model. The development of new technologies like advanced driver assistance systems or autonomous driving can only be accomplished efficiently using extensive simulation methods. Such kind of applications demand for computationally efficient vehicle models. This paper presents a steering system model for dual front axles of heavy duty trucks which supplements the suspension model of the axles. The model takes the torsional compliance of the steering column as well as the stiffness of the tie rods and the coupling rod into account. A quasi-static solution provides a straight forward computation including the partial derivatives required for an efficient implicit solver. The steering system model matches perfectly with comparatively lean, but sufficiently accurate multibody suspension models. KW - Steering System KW - Dual Axles KW - Multibody Model KW - Vehicle Dynamics KW - Real-Time Y1 - 2023 UR - https://www.researchgate.net/publication/369256274_Real-Time_capable_Multibody_Model_of_dual_Truck_Front_Axles PB - Springer ER - TY - RPRT A1 - Michael Sterner, A1 - Mareike Jentsch, A1 - Uwe Holzhammer, T1 - Energiewirtschaftliche und ökologische Bewertung eines Windgas-Angebotes N2 - In this technical report, (1) the benefits of the new technology for future energy supply are discussed, (2) the climate protection effect of wind gas is discussed, and (3) a reasonable use of wind energy for gas generation is analyzed. In particular, windgas in the heat market is discussed in the utilization cascade of wind energy. The new "power-to-gas" concept opens up completely new possibilities for the integration of renewable energies and for coupling the electricity and gas grids. The Sabatier process, which has been known for 100 years, was first developed for this purpose in 2008 under the leadership of the Center for Solar Energy and Hydrogen Research and Fraunhofer IWES (formerly ISET) with electrolysis to create the "power-to-gas" concept for energy storage. A first pilot plant was built by ZSW Stuttgart on behalf of SolarFuel in 2009. This plant proves the technical feasibility of the new technology. Renewable gas is stored, transported and used as required as control and reserve energy via reconversion, e.g. in combined cycle power plants. In this way, decentrally generated renewable electricity is converted into a CO2 -neutral energy carrier with high energy density. The key advantage of renewable methane is the use of existing infrastructure such as gas grids, gas storage and end-use equipment for the integration of renewable energy. Technologies for natural gas are state of the art and commercially available. Methane also has three times the energy density of hydrogen. T2 - Energy-economic and ecological evaluation of a windgas offer (Power-to-Gas) Y1 - 2011 U6 - https://doi.org/10.13140/RG.2.2.25093.68328 PB - Fraunhofer Institute for Energy Economics and Energy System Technology CY - Kassel ER - TY - RPRT A1 - Zacherl, Florian A1 - Wopper, Christoph A1 - Mieslinger, Johann A1 - Peis, Michael A1 - Rabl, Hans-Peter T1 - Schlussbericht zum Verbundvorhaben NAMOSYN: Nachhaltige Mobilität durch synthetische Kraftstoffe BT - Cluster FC1A: OME Für Dieselmotoren - Motorische Testung; Cluster FC2: C1-O Systeme für Ottomotoren N2 - Im Labor für Verbrennungsmotoren und Abgasnachbehandlung der OTH-Regensburg sollten im Zuge des NAMOSYN-Projektes zwei Vertreter klimaneutraler Kraftstoffe an verschiedenen Systemprüfständen (Motor-, Einspritzprüfstand, optisch zugängliche Einspritzkammer, …) und mit Hilfe von Simulationsmethoden für den Einsatz in bestehenden Verbrennungsmotoren untersucht werden. Synthetische Kraftstoffe aus der Gruppe der Oxymethylenether (OME) stellen eine CO2-neutrale Alternative zu fossilem Dieselkraftstoff dar. Für Ottomotoren wurde untersucht, ob der synthetische Kraftstoff DMC/MeFo (Dimethylcarbonat & Methylformiat) einen Ersatz für Ottokraftstoff darstellen kann, bzw. eine Drop-In-Fähigkeit gegeben ist. Die OTH Regensburg bearbeitete 2 unabhängige Teilvorhaben zur motorischen Testung von synthetischen Kraftstoffen: „FC 1A: Motorische Testung von OME“ und „FC 2: Untersuchung von C1-Oxygenaten für Ottomotoren“. Die Projektlaufzeit betrug 3,5 Jahre, inkl. kostenneutraler Verlängerung um 6 Monate aufgrund der Corona-Pandemie. Im FC1A "AP2-Nachrüstung Dieselmotoren" der OTH Regensburg lag der Fokus auf der Erforschung der Potentiale und der Umrüstung eines Einzylinder-Dieselmotors mit Pumpe-Leitung-Düse-(PLD)-Einspritzsystem des Projektpartners Motorenfabrik Hatz GmbH und Co. KG für OME-Betrieb. Im AP2.1 wurden umfangreiche Daten gesammelt und Simulationsmodelle des Motors und PLD-Einspritzsystems erstellt und mit Dieselkraftstoff und OME validiert. Nachfolgend wurden Parameterstudien zur Geometrie des Einspritzsystems und der physikalischen Eigenschaften von OME durchgeführt. In AP2.2 und AP2.3 wurden umfangreiche Untersuchungen an einem Motor- und Einspritzsystemprüfstand mit Diesel und OME durchgeführt und der Steuergerätedatensatz für den OME-Betrieb optimiert. Die Ergebnisse zeigen, dass die Umstellung des Kraftstoffs auf OME, insbesondere bei einfachen Motoren mit rudimentärer Einspritztechnik und ohne Mittel zur NOx-Reduzierung (keine AGR oder SCR), ein enormes Potenzial zur Steigerung des Wirkungsgrads bei gleichzeitiger Reduzierung aller regulierten Schadstoffe (NOx, 𝑃N, 𝑃M, CO und 𝑉OC) eröffnet. Die Ergebnisse und generierten Simulationsmodelle unterstützen eine schnelle Serienentwicklung und Einführung von OME-Umrüstlösungen. In FC 2 werden die vielversprechenden Kraftstoffe Methylformiat (MeFo) und Dimethylcarbonat (DMC) motorisch getestet. Untersuchungen am Kraftstoffsystem und wichtigen Komponenten dienen als Grundlage für das AP3. Im AP3 wird die Machbarkeit der DMC/MeFo-Verbrennung am Vollmotor demonstriert und die erwarteten Emissionsvorteile gegenüber herkömmlichen Ottokraftstoffen gezeigt. Abweichend von der ursprünglichen Planung werden an der OTH Regensburg Kraftstoffblends aus Benzin und MeFo untersucht, um den Einsatzbereich des Kraftstoffs zu erweitern. In AP5 werden potentielle Mischungsverhältnisse analysiert und die Eigenschaften der ausgewählten Kraftstoffmischungen an einem Einspritzratenprüfstand, an der Einspritzkammer und am Vollmotor untersucht. Es werden Einspritzverhalten, Gemischaufbereitung und Abgasemissionen bewertet. Zudem wird eine Kraftstoffmischanlage entwickelt und ein optischer Zugang am Vollmotor ermöglicht. Eine Ölverdünnungsmesstechnik wird eingesetzt, um den Kraftstoffeintrag ins Motoröl zu untersuchen KW - Synthetische Kraftstoffe KW - OME KW - DMC KW - MeFo KW - E-Fuels Y1 - 2023 CY - Regensburg ER - TY - JOUR A1 - Schümann, Malte A1 - Morich, J. A1 - Kaufhold, T. A1 - Böhm, Valter A1 - Zimmermann, Klaus A1 - Odenbach, Stefan T1 - A mechanical characterisation on multiple timescales of electroconductive magnetorheological elastomers JF - Magnetism and Magnetic Materials N2 - Magnetorheological elastomers are a type of smart hybrid material which combines elastic properties of a soft elastomer matrix with magnetic properties of magnetic micro particles. This leads to a material with magnetically controllable mechanical properties of which the magnetorheological effect is the best known. The addition of electroconductive particles to the polymer mix adds electrical properties to the material behaviour. The resulting electrical resistance of the sample can be manipulated by external magnetic fields and mechanical loads. This results in a distinct interplay of mechanical, electrical and magnetic effects with a highly complex time behaviour. In this paper a mechanical characterisation on multiple time scales was conducted to get an insight on the short and long-term electrical and mechanical behaviour of this novel material. The results show a complex resistivity behaviour on several timescales, sensitive to magnetic fields and strain velocity. The observed material exhibits fatigue and relaxation behaviour, whereas the magnetorheological effect appears not to interfere with the piezoresistive properties. Y1 - 2018 U6 - https://doi.org/10.1016/j.jmmm.2018.01.029 VL - 453 IS - May SP - 198 EP - 205 PB - Elsevier ER - TY - CHAP A1 - Ketterl, Hermann A1 - Heinrich, Tobias A1 - Reitmeier, Torsten A1 - Hoelscher, Clemens ED - Jäkel, Jens ED - Thiel, Robert T1 - Emissionsabhängige Leistungsregelung für BHKW’s T2 - Tagungsband AALE 2020: Automatisierung und Mensch-Technik-Interaktion, 17. Fachkonferenz, 4. bis 6. März 2020, Leipzig Y1 - 2020 SN - 978-3-8007-5180-8 VL - 2020 PB - VDE-Verlag ER - TY - JOUR T1 - Energieforschung BT - geförderte Projekte 2020 bis 2022 N2 - Über uns Das Regensburg Center of Energy and Resources (RCER) bündelt seit 2012 die Aktivitäten der Ostbayerischen Technischen Hochschule Regensburg (OTH Regensburg) und der regionalen Wirtschaftsunternehmen auf dem Strategiefeld „Energie und Ressourcen“. Mission: Energieforschung: vernetzen, voranbringen, vermitteln Das RCER fördert die Vernetzung verschiedener Disziplinen der Energieforschung innerhalb der OTH Regensburg und mit externen Partnern (Firmen, Förderträgern, Forschungsinstitutionen, öffentlichen Einrichtungen). Das RCER ist Ihr Partner beim Voranbringen von Kooperationen und Forschungsvorhaben durch Unterstützung in der Antragsphase, bei der Einwerbung von Projektmitteln und Projektbegleitung im Energiebereich. Das RCER steht für die Vermittlung von Know-how, Basiswissen, aktuellen Fragen und den Technologietransfer rund um das Thema Energie zwischen Wissenschaft, Wirtschaft, Gesellschaft und Politik. Vision Wir sind Ihr erster Ansprechpartner und Motor für innovative Energieforschung. Werte Verlässlichkeit, Kompetenz, Verantwortungsbewusstsein.Regional verwurzelt und weltoffen Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-65422 PB - OTH Regensburg ET - Ausgabe 2023 ER - TY - GEN A1 - Sterner, Michael T1 - Strom - Wärme - Verkehr - Industrie: das Zusammenspiel der Sektoren über Power-to-X T2 - Deutscher Ingenieurtag 2021, Düsseldorf 20. Mai 2021 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung Y1 - 2021 PB - VDI-Verlag ER - TY - JOUR A1 - Mikhaeil, Makram A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - On the application of adsorber plate heat exchangers in thermally driven chillers BT - An experimental and analytical study JF - Applied Thermal Engineering N2 - The effect of both heat and mass transfer characteristic lengths (HTCL, MTCL) of two different adsorber plate heat exchangers (APHE), for application in an adsorption chiller, on the adsorption and desorption kinetics is investigated. Three representative test frames (TF1-TF3) are prepared to examine small-scale adsorbent samples of the microporous silica gel (Siogel of Oker-Chemie, Germany) applying the volumetric large-temperature-jump methodology at different operating conditions. Based on the obtained kinetic data, an analytical model has been developed to predict the specific cooling power (SCP) and the coefficient of performance (COP) of a single-bed adsorption chiller comprising the studied APHEs. It turned out that, within the tested range of HTCL and MTCL, it can be concluded that, the adsorption kinetics are mainly influenced by the MTCL, while the desorption kinetics are dominated by the HTCL of the adsorbent domain. Applying Siogel as loose pellets inside a newly introduced APHE results in of 423.3 and 182.7 W⋅kg−1, at the evaporator temperatures of 15 °C and 5 °C, respectively. Herein, the condenser and adsorber-end temperatures amount to 30 °C and the desorption-end temperature to 90 °C. The corresponding s amount to 0.50 and 0.40, respectively, which represent quite promising results for further design optimizations. Y1 - 2023 U6 - https://doi.org/10.1016/j.applthermaleng.2022.119713 VL - 220 PB - Elsevier ER - TY - JOUR A1 - Frazzica, Andrea A1 - Palomba, Valeria A1 - Dawoud, Belal T1 - Thermodynamic Performance of Adsorption Working Pairs for Low-Temperature Waste Heat Upgrading in Industrial Applications JF - Applied Sciences N2 - The present work aims at the thermodynamic analysis of different working pairs in adsorption heat transformers (AdHT) for low-temperature waste heat upgrade in industrial processes. Two different AdHT configurations have been simulated, namely with and without heat recovery between the adsorbent beds. Ten working pairs, employing different adsorbent materials and four different refrigerants, have been compared at varying working boundary conditions. The effects of heat recovery and the presence of a temperature gradient for heat transfer between sinks/sources and the AdHT components have been analyzed. The achieved results demonstrate the possibility of increasing the overall performance when internal heat recovery is implemented. They also highlight the relevant role played by the existing temperature gradient between heat transfer fluids and components, that strongly affect the real operating cycle of the AdHT and thus its expected performance. Both extremely low, i.e., 40-50 degrees C, and low (i.e., 80 degrees C) waste heat source temperatures were investigated at variable ambient temperatures, evaluating the achievable COP and specific energy. The main results demonstrate that optimal performance can be achieved when 40-50 K of temperature difference between waste heat source and ambient temperature are guaranteed. Furthermore, composite sorbents demonstrated to be the most promising adsorbent materials for this application, given their high sorption capacity compared to pure adsorbents, which is reflected in much higher achievable specific energy. KW - adsorption KW - efficiency KW - heat transformer KW - heat upgrading KW - waste heat KW - working pairs Y1 - 2021 U6 - https://doi.org/10.3390/app11083389 VL - 11 IS - 8 PB - MDPI ER - TY - JOUR A1 - Thema, Martin A1 - Weidlich, Tobias A1 - Kaul, Anja A1 - Böllmann, Andrea A1 - Huber, Harald A1 - Bellack, Annett A1 - Karl, Jürgen A1 - Sterner, Michael T1 - Optimized biological CO2-methanation with a pure culture of thermophilic methanogenic archaea in a trickle-bed reactor JF - Bioresource Technology N2 - In this study, a fully automated process converting hydrogen and carbon dioxide to methane in a high temperature trickle-bed reactor was developed from lab scale to field test level. The reactor design and system performance was optimized to yield high methane content in the product gas for direct feed-in to the gas grid. The reaction was catalyzed by a pure culture of Methanothermobacter thermoautotrophicus IM5, which formed a biofilm on ceramic packing elements. During 600 h in continuous and semi-continuous operation in countercurrent flow, the 0.05 m3 reactor produced up to 95.3 % of methane at a methane production rate of 0.35 mCH43mR-3h-1. Adding nitrogen as carrier gas during startup, foam control and dosing of ammonium and sodium sulfide as nitrogen and sulfur source were important factors for process automation. KW - Biological methanation KW - Power-to-Gas KW - Reactor concept KW - Thermophilic archaea KW - Trickle-bed reactor Y1 - 2021 U6 - https://doi.org/10.1016/j.biortech.2021.125135 IS - 333 PB - Elsevier ER - TY - JOUR A1 - Gärtner, Sebastian A1 - Rank, Daniel A1 - Heberl, Michael A1 - Gaderer, Matthias A1 - Dawoud, Belal A1 - Haumer, Anton A1 - Sterner, Michael T1 - Simulation and Techno-Economic Analysis of a Power-to-Hydrogen Process for Oxyfuel Glass Melting JF - Energies N2 - As an energy-intensive industry sector, the glass industry is strongly affected by the increasingly stringent climate protection targets. As established combustion-based production systems ensure high process stability and glass quality, an immediate switch to low greenhouse gas emission processes is difficult. To approach these challenges, this work investigates a step-by-step integration of a Power-to-Hydrogen concept into established oxyfuel glass melting processes using a simulation approach. This is complemented by a case study for economic analysis on a selected German glass industry site by simulating the power production of a nearby renewable energy park and subsequent optimization of the power-to-hydrogen plant performance and capacities. The results of this study indicate, that the proposed system can reduce specific carbon dioxide emissions by up to 60%, while increasing specific energy demand by a maximum of 25%. Investigations of the impact of altered combustion and furnace properties like adiabatic flame temperature (+25 °C), temperature efficiency (∆ξ = −0.003) and heat capacity flow ratio (∆zHL = −0.009) indicate that pure hydrogen-oxygen combustion has less impact on melting properties than assumed so far. Within the case study, high CO2 abatement costs of 295 €/t CO2-eq. were determined. This is mainly due to the insufficient performance of renewable energy sources. The correlations between process scaling and economic parameters presented in this study show promising potential for further economic optimization of the proposed energy system in the future. KW - Power-to-Gas KW - Hydrogen KW - Electrolysis KW - Oxyfuel KW - Glass Industry Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-22713 N1 - Corresponding author: Sebastian Gärtner VL - 14 IS - 24 PB - MDPI ER - TY - JOUR A1 - Schorr, Philipp A1 - Zentner, Lena A1 - Zimmermann, Klaus A1 - Böhm, Valter T1 - Jumping locomotion system based on a multistable tensegrity structure JF - Mechanical systems and signal processing N2 - All known locomotion principles are limited respective to environmental conditions. Often, the occurrence of obstacles or gaps means the break-off for the operating motion systems. For such circumstances, a controllable jumping locomotion is required to cross these barriers. However, this locomotion demands sophisticated requirements to the actuation. The abrupt actuation is commonly realized by high dynamic actuators or complex mechanisms. In this work, a simple solution utilizing the multistability of a compliant tensegrity structure is described. Therefore, a two-dimensional tensegrity structure featuring four stable equilibria is considered. Based on bifurcation analyses a feasible actuation to control the current equilibrium configuration is derived. Changing between selected equilibrium states enables a great difference in potential energy, which yields a jumping motion of the structure. Based on numerical simulations a suitable actuation strategy is chosen to overcome obstacle and steps by jumping forward or backward, respectively. The theoretical approach is examined experimentally with a prototype of the multistable tensegrity structure. (c) 2020 Elsevier Ltd. All rights reserved. All known locomotion principles are limited respective to environmental conditions. Often, the occurrence of obstacles or gaps means the break-off for the operating motion systems. For such circumstances, a controllable jumping locomotion is required to cross these barriers. However, this locomotion demands sophisticated requirements to the actuation. The abrupt actuation is commonly realized by high dynamic actuators or complex mechanisms. In this work, a simple solution utilizing the multistability of a compliant tensegrity structure is described. Therefore, a two-dimensional tensegrity structure featuring four stable equilibria is considered. Based on bifurcation analyses a feasible actuation to control the current equilibrium configuration is derived. Changing between selected equilibrium states enables a great difference in potential energy, which yields a jumping motion of the structure. Based on numerical simulations a suitable actuation strategy is chosen to overcome obstacle and steps by jumping forward or backward, respectively. The theoretical approach is examined experimentally with a prototype of the multistable tensegrity structure. KW - Compliant tensegrity structure KW - Multibody dynamics KW - Multistability KW - Non-classical locomotion Y1 - 2021 U6 - https://doi.org/10.1016/j.ymssp.2020.107384 IS - 152 PB - Elsevier ER - TY - JOUR A1 - Emberger, Peter A1 - Altmann, Robert A1 - Gebhard, Jürgen A1 - Thuneke, Klaus A1 - Winkler, Markus A1 - Töpfer, Georg A1 - Rabl, Hans-Peter A1 - Remmele, Edgar T1 - Combustion characteristics of pure rapeseed oil fuel after injection in a constant volume combustion chamber with a non-road mobile machinery engine solenoid injector JF - Fuel N2 - Pure rapeseed oil fuel (R100) according to standard DIN 51605 is a greenhouse gas saving option for the mobility sector. With its high energy density close to diesel fuel, R100 is suitable to operate non-road mobile machinery with a high power demand and long operating time, where electric drives reach their limits. Advantages are indicated for its use in environmentally sensitive areas like agriculture since R100 is highly biodegradable and non-toxic. However, R100 is characterised by differing physical and chemical properties compared to diesel. The objective of the research is to investigate the differences in the ignition and combustion behaviour of R100 compared to diesel fuel (DF). For this purpose, a constant volume combustion chamber is used, which is equipped with a modern solenoid injector for engines of non-road mobile machinery. The researched injector shows a different hydraulic behaviour when using R100 compared to DF in that the injected fuel mass is lower with R100 than with DF. In combination with the 14 % by mass lower calorific value, less energy output is determined with R100. When varying the injection pressure, the impact on the ignition delay and combustion behaviour is much higher for R100 than for DF. Specifically, an increase of the injection pressure supports mixture preparation and thus partially compensates the differing physical properties of R100. The results of ignition delay measurements and net heat release analysis are as follows: At low load conditions with low injection pressure as well as a low combustion chamber temperature and pressure, R100 ignites later and shows a further delayed combustion compared to diesel. The opposite is observed for medium and high load conditions, where R100 ignites faster and without delayed combustion in comparison to DF. Thus, an adjustment of the heat release of R100 at the same level as for DF is possible by modifying the injection strategy. The research shows that for an optimised combustion of R100 the injection settings must be adjusted for every operation point separately. The results indicate how the injection parameters should be adjusted for different load conditions to realise a high-quality engine calibration for R100. KW - Constant volume combustion chamber KW - Ignition behaviour KW - Non-road mobile machinery KW - Rapeseed oil fuel KW - Solenoid injector KW - Straight vegetable oil fuel Y1 - 2022 U6 - https://doi.org/10.1016/j.fuel.2022.123979 IS - 320 PB - Elsevier ER - TY - CHAP A1 - Tremmel, Florian A1 - Nagler, O. A1 - Kutter, C. A1 - Holmer, Rainer T1 - Smart Cantilever Probe with Integrated Force and Acoustic Emission Sensor T2 - 2023 IEEE SENSORS, Vienna, Austria, 10/29/2023 - 11/1/2023 N2 - Acoustic emission (AE) testing recently found its application in the wafer testing sector of the semiconductor industry. To find out the mechanical robustness of semiconductor devices, contact pads on the chip surface are intentionally overstressed with an indenter tip and the appearing oxide cracks are detected with help of the generated AE signals. This is done in a customized test bench with a patented sensor-indenter system. This paper presents an improved version of the measurement setup that solves certain disadvantages of it and can be used in a standard wafer prober. The main components of the developed sensor system are a strain gauge for contact force measurement and a piezoelectric sensor element for AE signal detection. Both components are integrated on a cantilever beam which has an exchangeable indenter tip at its free end. The cantilever probe is electrically conductive to enable electrical tests via the indenter tip. This smart sensor-cantilever combination (SCC) can be mounted with several adapter components on a carrier plate to place it in a wafer prober. For both sensor elements amplifier circuits are developed to enhance their signal-to-noise ratios (SNRs). A prototype setup is shown together with simulated and experimental results to demonstrate its performance. The mechanical properties of the cantilever, as well as the force sensor and the AE crack signals, already fulfill the requirements for an implementation in a wafer prober. To further improve the sensor resolutions and detection limits, several optimizations regarding the design of the SCC are in progress. KW - Acoustic emission testing KW - piezoelectric sensor KW - strain gauge KW - operational amplifier circuit Y1 - 2023 SN - 979-8-3503-0387-2 U6 - https://doi.org/10.1109/SENSORS56945.2023.10325021 SP - 1 EP - 4 PB - IEEE ER - TY - JOUR A1 - Thema, Martin A1 - Bauer, Franz A1 - Sterner, Michael T1 - Power-to-Gas: Electrolysis and methanation status review JF - Renewable and Sustainable Energy Reviews N2 - This review gives a worldwide overview on Power-to-Gas projects producing hydrogen or renewable substitute natural gas focusing projects in central Europe. It deepens and completes the content of previous reviews by including hitherto unreviewed projects and by combining project names with details such as plant location. It is based on data from 153 completed, recent and planned projects since 1988 which were evaluated with regards to plant allocation, installed power development, plant size, shares and amounts of hydrogen or substitute natural gas producing examinations and product utilization phases. Cost development for electrolysis and carbon dioxide methanation was analyzed and a projection until 2030 is given with an outlook to 2050. The results show substantial cost reductions for electrolysis as well as for methanation during the recent years and a further price decline to less than 500 euro per kilowatt electric power input for both technologies until 2050 is estimated if cost projection follows the current trend. Most of the projects examined are located in Germany, Denmark, the United States of America and Canada. Following an exponential global trend to increase installed power, today's Power-to-Gas applications are operated at about 39 megawatt. Hydrogen and substitute natural gas were investigated on equal terms concerning the number of projects. KW - Biological CO2-Methanation KW - Chemical CO2-Methanation KW - Cost-development KW - Electrolysis KW - Power-to-Gas Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-26238 N1 - Corresponding author: Martin Thema VL - 112 IS - 7 SP - 775 EP - 787 PB - Elsevier ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk A1 - Prem, Nina T1 - Magnetically enhanced photoconductive high voltage control JF - ISSS Journal of Micro and Smart Systems N2 - The recent surge of interest in electrostatic actuators, particularly for soft robotic applications, has placed increasing demands on high voltage control technology. In this respect, optoelectronic bidirectional switching and analogue regulation of high voltages is becoming increasingly important. One common problem is the leakage current due to dark resistance of the material or device used. Another is the physical size of such elements. However, their ability to provide galvanic separation makes them a very attractive alternative to conventional (wired) semiconductor elements. This paper gives an overview of available methods and devices before introducing a concept based on the combination of photoresistive and magnetoresistive effects in Gallium Arsenide that are potentially applicable to other semiconductor materials. KW - GaAs KW - High voltage actuators KW - Magnetoresistance KW - Opto-sensors KW - Photoconduction KW - Soft robotics Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-30606 N1 - Corresponding author: Gareth J. Monkman VL - 11 SP - 317 EP - 328 PB - Springer Nature ER - TY - JOUR A1 - Haug, Sonja A1 - Vetter, Miriam T1 - Altersgerechtes Wohnen im Quartier JF - Standort - Zeitschrift für angewandte Geographie N2 - Im Alter nimmt das Quartier aufgrund geringerer Aktionsradien an Bedeutung zu. Der Beitrag befasst sich mit der Frage, welche Besonderheiten sich bei Senioren-Haushalten im Hinblick auf Wohnen und soziale Teilhabe zeigen. Aus dem Projekt MAGGIE werden Ergebnisse einer schriftlichen Haushaltsbefragung (N=195) in der Wohngenossenschaft Margaretenau Regensburg dargestellt. Hierbei wird auf die aktuelle und zukünftige Wohnsituation, den Veränderungsbedarf, den Wunsch nach Gemeinschaftsangeboten und die soziale Einbettung eingegangen. Es zeigt sich eine geringe Veränderungsbereitschaft und ein überdurchschnittlich hohes Maß an lokalem Sozialkapital. Am Ende werden Schlussfolgerungen für das Sanierungs- und Quartiersmanagement gezogen. T2 - Age-appropriate living in the neighborhood KW - Alter KW - Wohnen KW - Stadtviertel KW - Sozialraum KW - Senioren KW - Wohnsituation KW - Sozialraum KW - Lokales Sozialkapital KW - Quartiersgestaltung Y1 - 2021 U6 - https://doi.org/10.1007/s00548-020-00678-3 SN - 1432-220X N1 - Corresponding author: Sonja Haug VL - 45 SP - 11 EP - 17 PB - Springer Nature ER - TY - JOUR A1 - Hofrichter, Andreas A1 - Rank, Daniel A1 - Heberl, Michael A1 - Sterner, Michael T1 - Determination of the optimal power ratio between electrolysis and renewable energy to investigate the effects on the hydrogen production costs JF - International Journal of Hydrogen Energy N2 - Green hydrogen via renewable powered electrolysis has a high relevance in decarbonization and supply security. Achieving economically competitive hydrogen production costs is a major challenge in times of an energy price crisis. Our objective is to show the economically optimal installed capacity of electrolysers in relation to wind and solar power so swift and credible statements can be made regarding the system design. The ratio between renewable generation and electrolysis power as well as scaling effects, operating behaviour and development of costs are considered. Hydrogen production costs are calculated for four exemplary real PV and wind sites and different ratios of electrolysis to renewable power for the year 2020. The ideal ratio for PV systems is between 14% and 73% and for wind between 3.3% and 143% for low and high full load hours. The lowest hydrogen production costs are identified at 2.53 €/kg for 50 MW wind power and 72 MW electrolysis power. The results provide plant constructors the possibility to create a cost-optimized design via an optimum ratio of electrolysis to renewable capacity. Therefore, the procedures for planning and dimensioning of selected systems can be drastically simplified. Y1 - 2023 U6 - https://doi.org/10.1016/j.ijhydene.2022.09.263 SN - 0360-3199 N1 - Corresponding author: Michael Heberl N1 - Corrigendum to “Determination of the optimal power ratio between electrolysis and renewable energy to investigate the effects on the hydrogen production costs” [Int J Hydrogen Energy 48 (5) (2023) 1651–1663] - https://doi.org/10.1016/j.ijhydene.2023.03.128 VL - 48 IS - 5 SP - 1651 EP - 1663 PB - Elsevier ER - TY - JOUR A1 - Palomba, Valeria A1 - Nowak, Sebastian A1 - Dawoud, Belal A1 - Frazzica, Andrea T1 - Dynamic modelling of Adsorption systems: a comprehensive calibrated dataset for heat pump and storage applications JF - Journal of energy storage N2 - The growing efforts for the development of clean and efficient energy systems require the use of a multi-disciplinary approach and the integration of multiple generation appliances. Among the fields that can be considered enabling technologies, adsorption systems for air conditioning and thermal energy storages, are constantly increasing their maturity. However, for a proper design and integration of such systems, there is the need for a simulation framework that is reliable and computationally convenient. In the present paper, the implementation of a dynamic model for adsorption systems is presented, which includes different components (adsorber, phase changer, sorption materials) and is structured as a library. Modelica language and the commercial software Dymola (R) are used for the analysis. Data for different heat exchangers and working pairs are calibrated using experimental results and the calibrated model is subsequently used for the design of an adsorber based on a plate heat exchanger for thermal energy storage applications. The results proved that the model is fast and can reproduce experimental results with good accuracy, thus being a useful tool for the design and optimization of the different components of sorption systems. KW - CHILLERS KW - DIFFUSION KW - ETHANOL ADSORPTION KW - Optimization KW - PERFORMANCE KW - SCALE KW - simulation KW - THERMAL-ENERGY STORAGE KW - TRANSFORMATION KW - WATER-ADSORPTION Y1 - 2021 U6 - https://doi.org/10.1016/j.est.2020.102148 VL - 33 PB - Elsevier ER - TY - JOUR A1 - Bruni, S. A1 - Meijaard, J. P. A1 - Rill, Georg A1 - Schwab, A. L. T1 - State-of-the-art and challenges of railway and road vehicle dynamics with multibody dynamics approaches JF - Multibody System Dynamics N2 - A review of the current use of multibody dynamics methods in the analysis of the dynamics of vehicles is given. Railway vehicle dynamics as well as road vehicle dynamics are considered, where for the latter the dynamics of cars and trucks and the dynamics of single-track vehicles, in particular motorcycles and bicycles, are reviewed. Commonalities and differences are shown, and open questions and challenges are given as directions for further research in this field. KW - AUTOMATIC-GENERATION KW - BICYCLE DYNAMICS KW - Bicycles KW - CREEP FORCES KW - FREIGHT WAGON KW - LATERAL DYNAMICS KW - LINEAR-MODEL KW - Motorcycles KW - NON-HERTZIAN KW - PASSIVE RIDER KW - Railway vehicles KW - Review KW - Road vehicles KW - ROLLING-CONTACT KW - vehicle dynamics KW - WHEELSET-TRACK INTERACTION Y1 - 2020 U6 - https://doi.org/10.1007/s11044-020-09735-z VL - 49 IS - 1 SP - 1 EP - 32 PB - Springer ER - TY - JOUR A1 - Sterner, Michael A1 - Bauer, Franz T1 - Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland JF - Chemie-Ingenieur-Technik N2 - Um den Einfluss verschiedener Power-to-X-Verfahren auf die Transformation des deutschen Energiesystems und das Erreichen der Klimaschutzziele zu überprüfen, wurde ein sektorübergreifendes Energiesystemmodel entwickelt. Die daraus gewonnenen Ergebnisse zeigen: Für eine erfolgreiche Energiewende ist der Einsatz von Power-to-X in Zukunft unverzichtbar. Vor allem in Bereichen und Sektoren, in denen hohe Energiedichten erforderlich und nur wenig andere Optionen zur Defossilisierung vorhanden sind, werden Power-to-X-Technologien zwingend notwendig. T2 - Power-to-X in Context of Energy Transition and Climate Change Mitigation in Germany KW - Power-to-Gas KW - Climate mitigation KW - Energy system KW - Modeling KW - Power-to-X KW - Klimaschutz KW - Energiewende Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-11669 SN - 0009-286X N1 - Corresponding author: Franz Bauer VL - 92 IS - 1-2 SP - 85 EP - 90 PB - Wiley ER - TY - JOUR A1 - Sovacool, Benjamin K. A1 - Cabeza, Luisa F. A1 - Pisello, Anna Laura A1 - Colladon, Andrea Fronzetti A1 - Larijani, Hatef Madani A1 - Dawoud, Belal A1 - Martiskainen, Mari T1 - Decarbonizing household heating: Reviewing demographics, geography and low-carbon practices and preferences in five European countries JF - Renewable & Sustainable Energy Reviews N2 - What commonalities are there in sustainable or unsustainable heating practices in five high-income, high-emitting western European countries? What preferences do a nationally representative sample of the public in these countries hold towards low-carbon options? It is imperative that climate policy researchers and practitioners grapple with the difficulty of decarbonizing heat, which remains the largest single end-use service worldwide and which accounts about half of total final energy consumption. Based on a comparative assessment of five representative national surveys in Germany (N = 2009), Italy (N = 2039), Spain (N = 2038), Sweden (N = 2023), and the United Kingdom (N = 2000), this study explores the demographics and geography of household heat decarbonisation in Europe. By analyzing our country level data as well as our combined sample of 10,109 respondents, it investigates how people conceive of the purposes of low-carbon heat, their preferences for particular forms of heat supply, and their (at times odd) practices of heat consumption and temperature settings. Grounded in its original data, the study organizes its findings inductively across the five themes of literacy (heating knowledge, awareness and control), sustainability (heating practices, dynamics and conflicts), temperature (heating satisfaction and preferences), desirability of change (low-carbon heating priorities, business models and trust), and culture (country and national variation). The study also explores intersections between these dimensions, using multivariate analysis, as well as how preferences differ according to varying types of actors as well as geography and space. KW - Climate policy KW - Cooling KW - Energy policy KW - Heat decarbonisation KW - Household heat KW - Low-carbon heating KW - Space heating Y1 - 2021 U6 - https://doi.org/10.1016/j.rser.2020.110703 IS - 139 SP - 1 EP - 28 PB - Elsevier ER - TY - JOUR A1 - Mikhaeil, Makram A1 - Nowak, Sebastian A1 - Palomba, Valeria A1 - Frazzica, Andrea A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - Experimental and analytical investigation of applying an asymmetric plate heat exchanger as an evaporator in a thermally driven adsorption appliance JF - Applied Thermal Engineering N2 - This communication presents an experimental and analytical study on the evaporation mechanism in a closed-structured asymmetric plate heat exchanger (PHE) employed as a stagnant water evaporator for the application in an adsorption heat transformation appliance. To this aim, an experimental unit is constructed, which comprises two identical PHEs, one acting as an vaporator/condenser and the second, as an adsorber/desorber. Two endoscopes are mounted inside the investigated evaporator to visualize the evaporation mechanism when performing adsorption-evaporation processes under different boundary conditions. It turned out that the evaporation mechanism is a partially covered, thin film evaporation. A heat transfer analysis is performed to evaluate the heat transfer coefficient of the thin film evaporation () inside the investigated evaporator, resulting in -values between 1330 and 160 [W∙m−2∙K−1] over the investigated adsorption-evaporation time. Correlating the obtained () to the film thickness and the wetted area results in -values between 0.34 and 0.78 [mm] and wetted to total area ratios of 0.78 to 0.16. Besides, an analytical model has been developed and introduced to correlate the overall evaporator heat transfer coefficient with the adsorption potential and the time rate of change of the water uptake. KW - Adsorption-evaporation KW - Evaporator KW - Plate heat exchanger KW - Thin film evaporation Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-61115 N1 - Corresponding author: Belal Dawoud IS - 228 PB - Elsevier ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Sindersberger, Dirk A1 - Prem, Nina A1 - Diermeier, Andreas A1 - Szecsey, Tamara T1 - Dielectric behaviour of magnetic hybrid materials JF - Physical Sciences Reviews N2 - The objectives of this work include the analysis of electrical and magnetic properties of magneto-elastic hybrid materials with the intention of developing new techniques for sensor and actuator applications. This includes the investigation of dielectric properties at both low and high frequencies. The behaviour of capacitors whose dielectrics comprise magnetic hybrid materials is well known. Such interfacial magnetocapacitance can be varied according to magnetic content, magnetic flux density and the relative permittivity of the polymer matrix together with other dielectric content. The basic function of trapping electrical charges in polymers (electrets) is also established technology. However, the combination of magnetoactive polymers and electrets has led to the first electromagnetic device capable of adhering to almost any material, whether magnetically susceptible or not. During the course of this research, in addition to dielectrics, electrically conductive polymers based on (PDMS) matrices were developed in order to vary the electrical properties of the material in a targeted manner. In order to ensure repeatable results, this demanded new fabrication techniques hitherto unavailable. The 3D printing of silicones is far from being a mature technology and much pioneering work was necessary before extending the usual 3 d.o.f. to include orientation about and diffusion of particles in these three axes, thus leading to the concept of 6D printing. In 6D printing, the application of a magnetic field can be used during the curing process to control the particulate distribution and thus the spatial filler particle density as desired. Most of the devices (sensors and actuators) produced by such methods contain levels of carbonyl iron powder (CIP) embedded magnetic filler of up to 70 wt%. Contrary to this, a hitherto neglected research area, namely magnetoactive polymers (MAPs) having significantly lower magnetic particle concentrations (1 to 3 wt% CIP) were also investigated. With filler concentrations lower than 3 wt%, structures are formed which are completely absent at higher filler levels. CIP concentrations in the range of 1wt% demonstrate the formation of toroidal structures. Further development of coherent rings with a compact order results as filler concentrations increase towards 2 wt%. Above 3 wt% the structure eventually disintegrates to the usual random order found in traditional MAP with higher CIP content. Structured samples containing 1%–3 wt% CIP were investigated with the aid of X-ray tomography where solitary ring structures can be observed and eventually the formation of capillary doubles. Over wavelengths ranging from 1 to 25 µm, spectroscopic analysis of thin film MAP samples containing 2 wt% CIP revealed measurable magnetic-field-dependent changes in IR absorption at a wavenumber 2350 (λ = 4.255 µm). This was found to be due to the diamagnetic susceptibility of atmospheric carbon dioxide (CO2). Consequently, the first potential application for sparse matrix MAPs was found. KW - cappillary doublet KW - diamagnetic KW - elastomer dielectric KW - FTIR KW - interfacial magnetocapacitance KW - magnetoactive polymer KW - PDMS KW - toroid Y1 - 2021 U6 - https://doi.org/10.1515/psr-2019-0121 N1 - Corresponding author: Gareth J. Monkman VL - 7 IS - 10 SP - 1169 EP - 1185 PB - de Gruyter ER - TY - JOUR A1 - Mikhaeil, Makram A1 - Gaderer, Matthias A1 - Dawoud, Belal T1 - On the development of an innovative adsorber plate heat exchanger for adsorption heat transformation processes; an experimental and numerical study JF - Energy N2 - An innovative adsorber plate heat exchanger (APHE), which is developed for application in adsorption heat pumps, chillers and thermal energy storage systems, is introduced. A test frame has been constructed as a representative segment of the introduced APHE for applying loose grains of AQSOA-Z02. Adsorption kinetic measurements have been carried out in a volumetric large-temperature-jump setup under typical operating conditions of adsorption processes. A transient 2-D model is developed for the tested sample inside the setup. The measured temporal uptake variations with time have been fed to the model, through which a micro-pore diffusion coefficient at infinite temperature of 2 E−4 [m2s−1] and an activation energy of 42.1 [kJ mol−1] have been estimated. A 3-D model is developed to simulate the combined heat and mass transfer inside the APHE and implemented in a commercial software. Comparing the obtained results with the literature values for an extruded aluminium adsorber heat exchanger coated with a 500 μm layer of the same adsorbent, the differential water uptake obtained after 300 s of adsorption (8.2 g/100 g) implies a sound enhancement of 310%. This result proves the great potential of the introduced APHE to remarkably enhance the performance of adsorption heat transformation appliances. KW - Adsorber heat exchanger KW - Plate heat exchanger KW - Adsorption kinetics KW - Dynamic simulation Y1 - 2020 U6 - https://doi.org/10.1016/j.energy.2020.118272 N1 - Corresponding author: Belal Dawoud VL - 207 IS - September SP - 1 EP - 13 PB - Elsevier ER - TY - JOUR A1 - Monkman, Gareth J. A1 - Striegl, Birgit A1 - Prem, Nina A1 - Sindersberger, Dirk T1 - Electrical Properties of Magnetoactive Boron‐Organo‐Silicon Oxide Polymers JF - Macromolecular Chemistry and Physics N2 - The electrical properties of rheopectic magnetoactive composites comprising boron-organo-silicon oxide dielectric matrices containing carbonyl iron microparticles are presented for the first time. The increase in interfacial magnetocapacitance is seen to greatly exceed that experienced when using conventional elastomeric matrices such as polydimethylsiloxane. In addition to the increase in capacitance, a simultaneous and sharp decrease in the parallel electrical resistance over several orders of magnitude is also observed. The effects are time dependent but repeatable. Potential applications include magnetically controlled frequency dependent devices, magnetic sensor systems, weighting elements for neural networks, etc. Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-26488 N1 - Corresponding author: Gareth J. Monkman VL - 221 IS - 4 SP - 1 EP - 8 PB - Wiley ER - TY - JOUR A1 - Prem, Nina A1 - Sindersberger, Dirk A1 - Monkman, Gareth J. T1 - Infrared spectral analysis of low concentration magnetoactive polymers JF - Journal of Applied Polymer Science N2 - This work concerns an area of magnetoactive polymer (MAP) research seldom considered. Traditionally only MAP with high concentrations of magnetic filler (typically between 10 and 90 wt%) have been investigated. This article deals with a hitherto neglected aspect of research, namely MAP containing lower magnetic filler concentrations (1 to 3 wt%). This article utilizes a range of spectroscopic analysis methods (Raman and FTIR) and their applicability to MAP characterization at wavelengths ranging from 2.5 to 25 mu m. Particular attention is paid to low carbonyl iron particle (CIP) concentrations in MAP for which the emergence of capillary doublets at a critical 2 wt% concentration is revealed. This results in measurable magnetic field-dependent changes in IR absorption at a wavelength of 4.255 mu m together with a detectable CO2 susceptibility. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48366. KW - ELASTOMERS KW - magnetism and magnetic properties KW - sensors and actuators KW - spectroscopy Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-25913 SN - 1097-4628 N1 - Corresponding author: Nina Prem VL - 137 IS - 7 SP - 1 EP - 7 PB - Wiley ER - TY - JOUR A1 - Metsch, P. A1 - Schmidt, H. A1 - Sindersberger, Dirk A1 - Kalina, K. A. A1 - Brummund, J. A1 - Auernhammer, Günter A1 - Monkman, Gareth J. A1 - Kästner, Markus T1 - Field-Induced Interactions in Magneto-Active Elastomers BT - A Comparison of Experiments and Simulations JF - Smart Materials and Structures N2 - In this contribution, field-induced interactions of magnetizable particles embedded into a soft elastomer matrix are analyzed with regard to the resulting mechanical deformations. By comparing experiments for two-, three- and four-particle systems with the results of finite element simulations, a fully coupled continuum model for magneto-active elastomers is validated with the help of real data for the first time. The model under consideration permits the investigation of magneto-active elastomers with arbitrary particle distances, shapes and volume fractions as well as magnetic and mechanical properties of the individual constituents. It thus represents a basis for future studies on more complex, realistic systems. Our results show a very good agreement between experiments and numerical simulations—the deformation behavior of all systems is captured by the model qualitatively as well as quantitatively. Within a sensitivity analysis, the influence of the initial particle positions on the systems' response is examined. Furthermore, a comparison of the full three-dimensional model with the often used, simplified two-dimensional approach shows the typical overestimation of resulting interactions in magneto-active elastomers. Y1 - 2020 U6 - https://doi.org/10.1088/1361-665X/ab92dc N1 - Corrigendum: Field-induced interactions in magneto-active elastomers—a comparison of experiments and simulations (2020 Smart Mater. Struct. 29 085026); https://doi.org/10.1088/1361-665X/abb98b VL - 29 IS - 8 SP - 1 EP - 10 PB - IOPscience ER - TY - JOUR A1 - Schwanzer, Peter A1 - Schillinger, Maximilian A1 - Mieslinger, Johann A1 - Walter, Stefanie A1 - Hagen, Gunter A1 - Maerkl, Susanne A1 - Haft, Gerhard A1 - Dietrich, Markus A1 - Moos, Ralf A1 - Gaderer, Matthias A1 - Rabl, Hans-Peter T1 - A Synthetic Ash-Loading Method for Gasoline Particulate Filters with Active Oil Injection JF - SAR International Journal of Engines N2 - To reduce particulate emissions, the use of particulate filters in diesel engines is meanwhile state of the art, while the integration of such systems in gasoline engines is now also necessary in order to comply with today's regulations. Over its lifetime, a gasoline particulate filter (GPF) collects ash components of fuel, lubrication oil, and materials originating from the catalytic coating and from engine abrasion. In the development and application process, synthetic ashing from GPFs is challenging. The ash of the lubrication oil can be increased in various ways, like oil-doped fuel, a separate oil burner, or changes in the piston-cylinder system of the engine. However, these methods show major disadvantages. For this reason, an improved approach is presented in this study, which allows a quick response to changes in combustion (e.g., engine knocking) and producing ash, which is more realistic due to its primary particle size and the density of ash plugs, in a shorter time. Therefore, an approach to accelerate ash loading by active oil injection using a multi-point injection (MPI) system is introduced. With the help of this methodology, an ashing capacity of 1.21 g/h is implemented, which is a high rate compared to other investigations. The primary particle size (evaluated by means of a transmission electron microscope), is in the same size range as those detected at the full-load curve during regular operation. A computer tomographic (CT) analysis of the incinerated particulate filter also shows that a very high density of ash plugs can be realized, which has also been found in the literature for real applications. In addition, with the help of a mass spectrometer (MS) and an intermediate weighing of the particulate filter, the current ash loading of the GPF could be determined with an accuracy of 1%. KW - Ash KW - GDI KW - GPF KW - Particle Y1 - 2021 U6 - https://doi.org/10.4271/03-14-04-0029 SN - 1946-3936 SN - 1946-3944 VL - 14 IS - 4 SP - 493 EP - 506 PB - SAE International ER - TY - JOUR A1 - Schmidt, Henrik A1 - Straub, Benedikt B. A1 - Sindersberger, Dirk A1 - Bröckel, Ulrich A1 - Monkman, Gareth J. A1 - Auernhammer, Günter T1 - Collision and separation of nickel particles embedded in a Poly dimethylsiloxan matrix under a rotating magnetic field: A strong magneto active function JF - Colloid and Polymer Science N2 - In order to function as soft actuators, depending on their field of use, magnetorheological elastomers (MREs) must fulfill certain criteria. To name just a few, these can include rapid response to external magnetic fields, mechanical durability, mechanical strength, and/or large deformation. Of particular interest are MREs which produce macroscopic deformation for small external magnetic field variations. This work demonstrates how this can be achieved by just a small change in magnetic field orientation. To achieve this, (super)paramagnetic nickel particles of size ≈ 160 μm were embedded in a non-magnetic polydimethylsiloxan (PDMS) (661–1301 Pa) and their displacement in a stepwise rotated magnetic field (170 mT) recorded using a video microscope. Changes in particle aggregation resulting from very small variations in magnetic field orientation led to the observation of a new strongly magneto-active effect. This configuration is characterized by an interparticle distance in relation to the angle difference between magnetic field and particle axis. This causes a strong matrix deformation which in turn demonstrates hysteresis on relaxation. It is shown that the occurrence strongly depends on the particle size, particle distance, and stiffness of the matrix. Choosing the correct parameter combination, the state can be suppressed and the particle-matrix system demonstrates no displacement or hysteresis. In addition, evidences of non-negligible higher order magnetization effects are experimentally ascertained which is qualitatively in agreement with similar, already theoretically described, particle systems. Even at larger particle geometries, the new strongly magneto-active configuration is preserved and could create macroscopic deformation changes. Y1 - 2021 U6 - https://doi.org/10.1007/s00396-020-04784-4 VL - 299 SP - 955 EP - 967 PB - Springer ER - TY - JOUR A1 - Keiner, Dominik A1 - Thoma, Christian A1 - Bogdanov, Dmitrii A1 - Breyer, Christian T1 - Seasonal hydrogen storage for residential on- and off-grid solar photovoltaics prosumer applications: Revolutionary solution or niche market for the energy transition until 2050? JF - Applied Energy N2 - Appropriate climate change mitigation requires solutions for all actors of the energy system. The residential sector is a major part of the energy system and solutions for the implementation of a seasonal hydrogen storage system in residential houses has been increasingly discussed. A global analysis of prosumer systems including seasonal hydrogen storage with water electrolyser, hydrogen compressor, storage tank, and a fuel cell studying the role of such a seasonal household storage in the upcoming decades is not available. This study aims to close this research gap via the improved LUT-PROSUME model, which models a fully micro sector coupled residential photovoltaic prosumer system with linear optimisation for 145 regions globally. The modelling of the cost development of hydrogen storage components allows for the simulation of a residential system from 2020 until 2050 in 5-year steps in hourly resolution. The systems are cost-optimised for either on- or off-grid operation in eight scenarios including battery electric vehicles, which can act as an additional vehicle-to-home electricity storage for the system. Results show that implementation of seasonal hydrogen systems only occurs in least cost solutions in high latitude countries when the system is forced to run in off-grid mode. In general, a solar photovoltaic plus battery system including technologies that can cover the heat demand is the most economic choice and can even achieve lower cost than a full grid supply in off-grid operation for most regions until 2050. Additional parameters including the self-consumption ratio, the demand cover ratio, and the heat cover ratio can therefore not be improved by seasonal storage systems if economics is the main deciding factor for a respective system. Further research opportunities and possible limitations of the system are then identified. KW - Battery KW - Electrolyser KW - Fuel Cell KW - Hydrogen KW - ProsumerIridium KW - Residential seasonal storage KW - Rooftop solar photovoltaics Y1 - 2023 U6 - https://doi.org/10.1016/j.apenergy.2023.121009 VL - 340 PB - Elsevier ER - TY - CHAP A1 - Rieger, Anna A1 - Oetjen, Arne A1 - van de Par, Steven A1 - Rabl, Hans-Peter T1 - Gehörbezogene Modellierung der Dissonanz T2 - Tagungsband DAGA 2021: 47. Jahrestagung für Akustik, 15.-18. August 2021, Wien und Online Y1 - 2021 UR - https://www.dega-akustik.de/publikationen/online-proceedings/ VL - 47 SP - 1034 EP - 1037 PB - Deutsche Gesellschaft für Akustik e.V. ER - TY - CHAP A1 - Frauenschläger, Tobias A1 - Dentgen, Manuel A1 - Mottok, Jürgen T1 - Systemarchitektur eines Sicherheitsmoduls im Energiesektor T2 - Tagungsband 2. Symposium Elektronik und Systemintegration ESI 2020: "Intelligente Systeme und ihre Komponenten: Forschung und industrielle Anwendung" N2 - Aufgrund der immer weiter anwachsenden Vernetzung der Stromnetze wird die Kommunikation zwischen der Leitstelle des Energieversorgers und den Infrastrukturkomponenten innerhalb eines Umspannwerks immer bedeutsamer. Dabei werden sowohl Steuerbefehle als auch Daten für Überwachungsfunktionen übertragen. In den aktuellen Netzwerkarchitekturen findet diese Kommunikation ohne eine kryptografische Absicherung statt, was einen Angriffspunkt für gezielte Attacken und damit eine potenzielle Gefährdung der Energieversorgung darstellt. Um solchen Angriffen in Zukunft entgegenzuwirken, wird das ES³M-Sicherheitsmodul entwickelt. Dieses soll in das Netzwerk zwischen den beiden Kommunikationspartnern eingesetzt werden und so den Datenverkehr absichern. Mithilfe einer Bedrohungsanalyse wurden Anforderungen abgeleitet, die neben kryptografischen Maßnahmen auch Themen wie funktionale Sicherheit und Langlebigkeit umfassen. Um diese zu erfüllen, wurde eine spezielle Systemarchitektur auf Basis einer Aufgabenteilung entworfen. Diese Architektur und korrespondierende Designentscheidungen werden präsentiert. Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-2092 N1 - Die Konferenzveröffentlichung erschien im Band "Fachbeiträge 2. Symposium Elektronik und Systemintegration ESI 2020" mit dem Titel „Intelligente Systeme und ihre Komponenten: Forschung und industrielle Anwendung“. Die Fachtagung, geplant für den 01. April 2020 an der Hochschule Landshut, wurde aufgrund der Corona-Pandemie abgesagt, die eingereichten Fachbeiträge im Band veröffentlicht. Hrsg.: Artem Ivanov, Marc Bicker und Peter Patzelt. Hochschule Landshut, 2020, ISBN 978-3-9818439-4-1 SP - 29 EP - 38 CY - Landshut ER - TY - CHAP A1 - Lalo, Erjola A1 - Sailer, Andreas A1 - Mottok, Jürgen A1 - Siemers, Christian T1 - Overhead-Aware Schedule Synthesis for Logical Execution Time (LET) in Automotive Systems T2 - 2022 IEEE 35th International System-on-Chip Conference (SOCC): 05-08 September 2022, Belfast, United Kingdom N2 - The Logical Execution Time (LET) has recently been integrated in multi-core automotive systems to ensure timing and dataflow determinism. Although buffering mechanisms are introduced to incorporate LET semantics, they do not guarantee that tasks are executed within their LET frames. In fact, LET and buffering semantics are violated if scheduling is not designed to execute all tasks within their LET frames and in a specific order. In this paper, we describe a scheduling synthesis technique for Fixed-Priority Scheduling (FPS) to achieve resource-efficient execution of LET systems. The proposed approach considers LET semantics, scheduling overheads, and delays caused by operating system operations and provides the possibility to optimize the schedule with respect to aspects like scheduling overheads. Our performance and feasibility evaluation shows that the proposed algorithm provides results in a reasonable amount of time for models of complex industrial applications. Thus, the integration of the proposed algorithm into an automated process is of high benefit to accelerate the development of vehicle applications. Y1 - 2022 SN - 978-1-6654-5985-3 U6 - https://doi.org/10.1109/SOCC56010.2022.9908103 SP - 1 EP - 6 PB - IEEE ER - TY - CHAP A1 - Mucha, Matthias A1 - Mottok, Jürgen A1 - Krämer, Stefan T1 - Estimation of Worst Case Response Time Boundaries in Multi-Core Real-Time Systems T2 - 2017 International Conference on Applied Electronics (AE), 5-6 Sept. 2017, Pilsen N2 - We address a novel probabilistic approach to estimate the Worst Case Response Time boundaries of tasks. Multi-core real-time systems process tasks in parallel on two or more cores. Tasks in our contribution may preempt other tasks, block tasks with semaphores to access global shared resources, or migrate to another core. The depicted task behavior is random. The shape of collected response times of a task within a processing time is multimodal. Extreme Value approaches need unimodal response time distributions to estimate the Worst Case Response Time of tasks. The new proposed method derives a set of three task set shapes from the source task set. It is used to minimize the uncertainty of random task behavior by maximizing the coverage of possible Worst Case Response Times. The case study evaluates the new proposed estimation method by the use of dynamically generated random tasks with varying task properties. Y1 - 2017 SN - 978-80-261-0641-8 U6 - https://doi.org/10.23919/ae.2017.8053598 SN - 1803-7232 SP - 1 EP - 6 PB - IEEE ER - TY - JOUR A1 - Federrath, H. A1 - Mottok, Jürgen A1 - Plößl, K. A1 - Völkl, Thomas T1 - Automotive safety and security JF - Jahresrückblick 2007 des Bayerischen IT-Sicherheitsclusters Y1 - 2007 ER - TY - CHAP A1 - De, Sangita A1 - Niklas, Michael A1 - Rooney, Brian A1 - Mottok, Jürgen A1 - Brada, Premek T1 - Towards Translation of Semantics of Automotive Interface Description Models from Franca to AUTOSAR Frameworks BT - An Approach using Semantic Synergies T2 - 2019 International Conference on Applied Electronics (AE), 10-11 Sept. 2019, Pilsen, Czech Republic N2 - The automotive industry is eventually evolving into a complex network of services. The heterogeneous and distributed nature of automotive software systems demands flexible software components which can operate in different environments. Because of heterogeneous automotive development environments, the domain experts, must cope with too many diversities, adaption layers, and incompatibilities to design applications for the current generation of autonomous driving vehicles. In this context, interface adaptation is a promising approach to achieve flexibility without directly changing the respective components. AUTOSAR, which is the de-facto standard for describing automotive system architecture and is a hugely comprehensive standard allowing designers full control from abstract system description to bare metal level deployment. However, the vehicle subsystems have still evolved to include multifarious high-level domains not covered by AUTOSAR e.g. Infotainment, Telematics etc. Therefore, it seems beneficial to bridge the semantic gaps between AUTOSAR applications and other standards of automotive application domains. The goal of this paper is to investigate interface semantic mapping and achieve transparent integration of domain-specific applications using the translation of semantics among the AUTOSAR platform software component models and other software components models of open source development platforms e.g. GENIVI. A key goal of such a modelling approach is the reuse of existing interface description languages and respective code generators. This will enhance future interoperability and decrease in incompatibility among these platforms. KW - Adaptation models KW - ARXML KW - Automotive engineering KW - component model KW - Connectors KW - FRAMEWORK KW - Franca IDL KW - interface KW - Receivers KW - semantic KW - synergy KW - traits Y1 - 2019 U6 - https://doi.org/10.23919/AE.2019.8867018 SP - 1 EP - 6 PB - University of West Bohemia ER -