TY - JOUR A1 - Kurzweil, Peter A1 - Shamonin (Chamonine), Mikhail T1 - State-of-Charge Monitoring by Impedance Spectroscopy during Long-Term Self-Discharge of Supercapacitors and Lithium-Ion Batteries JF - Batteries N2 - Frequency-dependent capacitance C(ω) is a rapid and reliable method for the determination of the state-of-charge (SoC) of electrochemical storage devices. The state-of-the-art of SoC monitoring using impedance spectroscopy is reviewed, and complemented by original 1.5-year long-term electrical impedance measurements of several commercially available supercapacitors. It is found that the kinetics of the self-discharge of supercapacitors comprises at least two characteristic time constants in the range of days and months. The curvature of the Nyquist curve at frequencies above 10 Hz (charge transfer resistance) depends on the available electric charge as well, but it is of little use for applications. Lithium-ion batteries demonstrate a linear correlation between voltage and capacitance as long as overcharge and deep discharge are avoided. KW - aging KW - capacitance KW - self-discharge KW - state-of-charge monitoring KW - supercapacitor Y1 - 2018 U6 - https://doi.org/10.3390/batteries4030035 VL - 4 IS - 3 SP - 1 EP - 13 PB - MPDI ER - TY - GEN A1 - Weiss, Nils T1 - Vulnerabilities of OBD2 Dongles T2 - RCAR Annual Conference, 2018, Munich, Germany Y1 - 2018 ER - TY - CHAP A1 - Fuhrmann, Thomas A1 - Niemetz, Michael T1 - Transdisciplinary Bachelor Course Connecting Business and Electrical Engineering T2 - 4th International Conference on Higher Education Advances (HEAd'18), 2018, Universitat Politècnica de València, València N2 - The OTH Regensburg has a broad variety of study programs in technical, business, social and health sciences. Up to now there is no integral connection in the bachelor curricula between business and technical faculties except for some small subjects. The scope of this project is to develop a new course specialization which connects engineering and business thinking. Electrical engineering students should learn basics of business science and how managers think. Business students should vice versa learn fundamentals of engineering and how engineers solve problems. Students from both faculties work together in projects where they act like start-up companies developing a new product and bringing it into the market. It is seen a transdisciplinary effect: These projects gain innovative results between the disciplines compared to student projects of one isolated discipline. Evaluation results from the first two cohorts indicate high student satisfaction, high learning success as well as directions for further improvement. KW - Business Education KW - Engineering Education KW - Project Based Learning KW - Transdisciplinary Education Y1 - 2018 U6 - https://doi.org/10.4995/HEAd18.2018.8056 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 - Böhm, Valter A1 - Schorr, Philipp A1 - Zimmermann, Klaus A1 - Zentner, Lena T1 - An Approach to the Estimation of the Actuation Parameters for Mobile Tensegrity Robots with Tilting Movement Sequences T2 - 2018 International Conference on Reconfigurable Mechanisms and Robots (ReMAR); 20-22 June 2018; Delft, Netherlands N2 - This paper deals with the locomotion by tilting sequences of shape-variable compliant tensegrity structures. The shape of these structures is controlled by manipulating their prestress state. The tensegrity structure is tilting as consequence of a suitable variation of its shape. By multiple repetition of such tilting sequences a motion is generated. Quasi-static considerations for the considered structures are presented in order to estimate the actuation parameters. For a proper number of actuators this quasi-static approach enables an analytical calculation of the actuation parameters of the structure in order to control the geometrical configuration as required. As an example a two-dimensional tensegrity structure which is in contact with a horizontal plane due to gravity is considered. By successive tilting sequences a uniaxial motion results. The excitation of the structure is calculated for a given change of shape with the quasi-static analysis. The according results are compared with transient dynamic simulations. Qualitative conclusions about the motion behavior and the usability of the quasi-static approach are given. KW - mobile robots KW - motion control KW - robot dynamics KW - structural engineering Y1 - 2018 U6 - https://doi.org/10.1109/REMAR.2018.8449871 SP - 1 EP - 8 PB - IEEE ER - TY - CHAP A1 - Mäule, Paul A1 - Rabl, Hans-Peter T1 - Correlation of Oil Emissions with Particulate Emissions of Gasoline Engines T2 - Internationales AVL-Forum Abgas- und Partikelemissionen, 20. und 21. Februar 2018, Ludwigsburg N2 - Recent developments in exhaust gas legislation make it necessary to focus the research at the particulate emissions from gasoline engines and technologies for their reduction. In addition to the particulates resulting from the combustion of the fuel, the oil emissions represent another possible source for particulate emissions. This paper presents a measurement method which can be used to quantify stationary as well as dynamic oil emissions of gasoline engines. Furthermore, the correlation between the oil emissions and the particulate emissions is the focus of the investigations. Conventional methods for the determination of the oil emissions, such as the gravimetric and the volumetric measurement, are unsuitable since they require long engine operation times to provide useful results. These methods therefore do not allow a fast online measurements during the dynamic operation. For this reason, a new measuring method was used, which allows for a time-resolved online measurement of the oil emissions. This measurement method is based on the sulfur tracer method, which uses the sulfur that is naturally contained in the engine oil as a tracer. The sulfur concentration in the exhaust gas is determined by using an Ion-Molecule-Reaction mass spectrometer. The determination of the particulate emissions corresponds to the PMP regulation. The studies carried out under steady state and dynamic conditions show a clear correlation between the oil consumption and the number of particulates in the exhaust gas. In the case of the dynamic measurements it could also be shown that time-resolved measurements of the oil consumption are possible with the used measurement setup. In addition, it was shown that the number of particulates does not influence the measurement of the SO2-concentration. Furthermore, the different effects of burned and unburned oil emissions have been evaluated by the dosing of the oil into the exhaust gas. The overall conclusion of the measurements shows a strong influence of the oil emissions on the particulate emissions. Therefore, it is crucial to reduce the oil emissions. Possible approaches for this reduction can be improved turbocharger sealing concepts, new piston ring designs or more efficient oil separators for the crankcase ventilation system. KW - Auspuffgas KW - Benzinmotor KW - dynamisches Messen KW - Kraftstoff KW - Maschinenbetrieb KW - Massenspektrometer KW - Messmethode KW - Messtechnik KW - Motorenöl KW - Ölverbrauch KW - Online-Messung KW - Partikelemission KW - Schwefel KW - Tracer-Technik KW - Volumenmessung KW - Zeitmessung Y1 - 2018 SP - 1 EP - 9 PB - AVL Deutschland CY - Mainz ER - TY - CHAP A1 - Smolareck, Elisabeth A1 - Faisst, Holger A1 - Schneider, Ralph T1 - Modellbasierte Korrektur von Inertialsensor-Signalen – Ein Schritt auf dem Weg zum hochautomatisierten Fahren T2 - Konferenz: AALE 2018 - 15. Fachkonferenz, Das Forum für Fachleute der Automatisierungstechnik aus Hochschulen und Wirtschaft 01.03.2018 - 02.03.2018 in Köln, Deutschland N2 - Infolge neuer Zielsetzungen im Automobilbereich, wie z. B. der Weiterentwicklung von Fahrerassistenzsystemen hin zum hochautomatisierten Fahren (HAF), ergeben sich erhöhte Anforderungen an die Signalgüte der im Fahrzeug eingesetzten Inertialsensoren für Drehraten und Beschleunigungen. Da deren Erfüllung über einen hardwarebasierten Ansatz nicht immer möglich und sinnvoll ist, strebt die Firma Continental eine Software-Lösung zur modellbasierten Verbesserung dieser Sensorsignale an. KW - Automobilindustrie KW - Beschleunigung KW - Fahrerassistenzsystem KW - Inertialsensor KW - Software-Lösung Y1 - 2018 UR - http://www.vde-verlag.de/proceedings-de/564522017.html SN - 978-3-8007-4522-7 SP - 1 EP - 10 PB - VDE-Verlag CY - Berlin ER - TY - JOUR A1 - Rösel, Birgit T1 - Just-in-Time Teaching für einen Grundkurs Regelungstechnik – Ergebnisse und Auswirkungen der Profistufe des Zertifikats Hochschullehre JF - Didaktiknachrichten Y1 - 2018 UR - https://diz-bayern.de/DiNa/06_2018 IS - 06 SP - 66 EP - 71 PB - Zentrum für Hochschuldidaktik (DiZ) ER - TY - CHAP A1 - Schorr, Philipp A1 - Böhm, Valter A1 - Zentner, Lena A1 - Zimmermann, Klaus T1 - Dynamical Investigation of Crawling Motion System based on a Multistable Tensegrity Structure T2 - Proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics : Porto, Portugal, 29.07.2018 - 31.07.2018 N2 - The basic idea of this article is the utilization of the multistable character of a compliant tensegrity structure to control the direction of motion of a crawling motion system. A crawling motion system basing on a two-dimensional tensegrity structure with multiple stable equilibrium states is considered. This system is in contact with a horizontal plane due to gravity. For a selected harmonic actuation of the system small oscillations around the given equilibrium state of the tensegrity structure occur and the corresponding uniaxial motion of the system is evaluated. A change of the equilibrium state of the tensegrity structure yields to novel configuration of the entire system. Moreover, the motion behavior of the novel configuration is totally different although the actuation strategy is not varied. In particular, the direction of motion changes. Therefore, this approach enables a uniaxial bidirectional crawling motion with a controllable direction of motion using only one actuat or with a selected excitation frequency. Y1 - 2018 SN - 978-989-758-321-6 U6 - https://doi.org/10.5220/0006852701220130 SP - 122 EP - 130 PB - SCITEPRESS ER - TY - CHAP A1 - Rösel, Birgit A1 - Köhler, Thomas T1 - First results of a new digitalized concept for teaching control theory as minor subject at a university of applied science T2 - 2018 IEEE Global Engineering Education Conference (EDUCON), 17-20 April 2018, Santa Cruz de Tenerife, Spain N2 - This paper presents a digitalized concept for teaching control theory as minor subject with an integrated approach for lectures, exercises and practical sessions and first results of the implementation at the department of electrical engineering at the OTH Regensburg. The concept uses activating methods like blended learning and possibilities of digitalization of teaching implementing Just in Time Teaching and Peer Instruction. The base of the new concept is the idea of constructive alignment. Furthermore this paper presents the feedback of the students along with an accompanying scientific research over several semesters. The data obtained from the presented module are compared with the data from other blended learning approaches in Germany. KW - Blended Learning KW - constructive alignment KW - Control theory KW - Electrical engineering KW - Electronic learning KW - Just in Time Teaching KW - Task analysis KW - taxonomy KW - teaching text Y1 - 2018 U6 - https://doi.org/10.1109/EDUCON.2018.8363217 SP - 118 EP - 125 PB - IEEE ER - TY - JOUR A1 - Sýkora, Miroslav A1 - Diamantidis, Dimitris A1 - Holický, Milan A1 - Marková, Jana A1 - Rózsás, Árpád T1 - Assessment of compressive strength of historic masonry using non-destructive and destructive techniques JF - Construction and Building Materials N2 - Masonry structures were built by various techniques using different materials, the properties of which exhibit a considerable scatter dependent on periods of construction and region-specific conditions. For historic structures with a heritage value, various non- or minor-destructive tests (NDTs) are commonly applied, while the application of destructive tests (DTs) is minimized. The contribution is based on investigations of 15 historic stone and clay brick masonry structures, for which NDT strengths of masonry units are verified by DTs. The proposed operational approach makes it possible to account for statistical uncertainty due to a limited number of DTs used to calibrate NDTs. KW - Calibration KW - Clay bricks KW - Compressive strength KW - Mortar KW - Non-destructive test KW - Statistical analysis KW - Stone masonry KW - Uncertainty Y1 - 2018 U6 - https://doi.org/10.1016/j.conbuildmat.2018.10.180 VL - 193 IS - December SP - 196 EP - 210 PB - Elsevier ER - TY - JOUR A1 - Kaspar, Marcel A1 - Rabl, Hans-Peter A1 - Mayer, Wolfgang T1 - Ion-Molecule Reaction for the Selective Detection of Hydrocarbons in Diesel Exhaust Gas JF - Chemie Ingenieur Technik N2 - The hydrocarbons present in the diesel exhaust gas are analyzed. A mass spectrometer is used for the measurements, and it operates on the basis of an ion-molecule reaction. This method is especially suitable because it is selective, is as free of fragments as possible, and is highly sensitive to the species that need to be measured. The study shows that numerous hydrocarbons in diesel exhaust gas can be identified. In particular, three molecules, ethyne, ethene and propene, were analyzed online in-depth on an engine test bench under different engine operating conditions. KW - Diesel exhaust gas KW - Hydrocarbons KW - Ion-molecule reaction KW - Mass spectrometry Y1 - 2018 U6 - https://doi.org/10.1002/cite.201700075 VL - 90 IS - 6 SP - 826 EP - 834 PB - WILEY-VCH ER - TY - JOUR A1 - Schorr, Philipp A1 - Böhm, Valter A1 - Zentner, Lena A1 - Zimmermann, Klaus T1 - Motion characteristics of a vibration driven mobile tensegrity structure with multiple stable equilibrium states JF - Journal of Sound and Vibration N2 - A novel type of a vibration driven motion system based on a compliant tensegrity structure with multiple stable equilibrium states is considered. These equilibrium configurations correspond to different prestress states with different dynamical properties. Therefore, the motion characteristics can be varied by changing the equilibrium state. For the application in the fields of mobile robotics, these discrete adjustable dynamics are advantageous. The vibration modes of the structure as well as the corresponding motion characteristics of the system can be adapted to the given environmental conditions in order to ensure a reliable motion. In this paper, dynamical investigations of an exemplary two-dimensional multistable tensegrity structure are considered. For the chosen parameter values the structure features two relevant equilibrium configurations. The resulting motion system is in contact to a horizontal plane due to gravity and the actuation is realized by the harmonic variation of the length of a single tensioned member. The motion of the system is simulated for various actuation frequencies with the different equilibrium states as an initial configuration. A uniaxial or a planar movement occurs depending on the selection of the actuated member within the tensegrity structure. The steady state motion is evaluated regarding motion characteristics like the steady state velocity. Moreover, the influences on the motion behavior caused by the different equilibrium states as an initial condition are emphasized. (C) 2018 Elsevier Ltd. All rights reserved. KW - Compliant tensegrity structure KW - LOCOMOTION KW - Multistability KW - Vibration driven motion Y1 - 2018 U6 - https://doi.org/10.1016/j.jsv.2018.09.019 VL - 437 IS - December SP - 198 EP - 208 PB - Elsevier ER - TY - JOUR A1 - da Silva Mota, Fabio Antonio A1 - Hinckel, Jose Nivaldo A1 - Rocco, Evandro Marconi A1 - Schlingloff, Hanfried T1 - Modeling and Analysis of a LOX/Ethanol Liquid Rocket Engine JF - Journal of Aerospace Technology and Management N2 - This work studies the performance and dry mass of the under development LOX/Ethanol L75 liquid rocket engine. To this end, an object-oriented program written in C++ was developed. The program is intended to be versatile and easily extensible in order to analyze different configurations of liquid rocket engines. The UML (Unified Modeling Language) tool is used to model the architecture of the codes. UML diagrams help to visualize the code structure and the communication between objects, enabling a high degree of abstraction. The cryogenics Vulcain and HM7B engines power cycles along with the staged-combustion SSME engine perform the verification of the codes. Finally, the influence of changes in design parameters on the performance and dry mass of the L75 rocket engine is analyzed. KW - Ethanol KW - Liquid rocket engines KW - Modeling Y1 - 2018 U6 - https://doi.org/10.5028/jatm.v10.914 VL - 10 PB - Inst Aeronautica & Espaco-IAE ER - TY - JOUR A1 - Braun, Peter A1 - Gebhard, Jürgen A1 - Matysik, Frank-Michael A1 - Rabl, Hans-Peter T1 - Potential Technical Approaches for Improving Low-Temperature NOx Conversion of Exhaust Aftertreatment Systems JF - Chemie Ingenieur Technik N2 - Lean-burn engines, such as diesel engines, are widely used in mobile and stationary applications. Operation of lean-burn engines leads to formation of distinct amounts of nitrogen oxides (NO and NO2). Efficient aftertreatment is mandatory to meet legal requirements, especially at low exhaust temperatures, as for the future a decline of the exhaust temperature level can be predicted due to improved engine efficiencies. Within this review, potential technical solutions to enhance the DeNO(x)-aftertreatment efficiency at low exhaust temperatures are presented. KW - DECOMPOSITION KW - Diesel Engine KW - Exhaust aftertreatment KW - IMPACT KW - Low-temperature DeNO(x) KW - NH3 KW - NITRIC-OXIDE KW - Nitrogen oxides KW - OXIDE CATALYST KW - PERFORMANCE KW - PYROLYSIS KW - SCR KW - Selective catalytic reduction KW - SELECTIVE CATALYTIC-REDUCTION KW - UREA HYDROLYSIS Y1 - 2018 U6 - https://doi.org/10.1002/cite.201700122 VL - 90 IS - 6 SP - 762 EP - 773 PB - WILEY-VCH ER - TY - JOUR A1 - Barz, Tilman A1 - Seliger, Dominik A1 - Marx, Klemens A1 - Sommer, Andreas A1 - Walter, Sebastian F. A1 - Bock, Hans Georg A1 - Koerkel, Stefan T1 - State and state of charge estimation for a latent heat storage JF - Control Engineering Practice N2 - A nonlinear state observer is designed for a thermal energy storage with solid/liquid phase change material (PCM). Using a physical 2D dynamic model, the observer reconstructs transient spatial temperature fields inside the storage and estimates the stored energy and the state of charge. The observer has been successfully tested with a lab-scale latent heat storage with a single pass tube bundle and the phase change material located in a shell around each tube. It turns out that the observer robustly tracks the real process data with as few as four internal PCM temperature sensors. © 2017 Elsevier Ltd. All rights reserved. KW - Heat conduction in cylindrical shell KW - Kalman filter KW - Latent heat thermal energy storage (LHTES) KW - MODEL KW - Nonlinear state observer KW - OF-THE-ART KW - Orthogonal collocation KW - PCM KW - PERFORMANCE ENHANCEMENT TECHNIQUES KW - PHASE-CHANGE MATERIAL KW - POLYETHYLENE KW - Reduced model KW - simulation KW - Solidification KW - State of charge (SOC) KW - SYSTEMS KW - THERMAL-ENERGY STORAGE Y1 - 2018 U6 - https://doi.org/10.1016/j.conengprac.2017.11.006 VL - 72 SP - 151 EP - 166 PB - Pergamon-Elsevier d. ER - TY - JOUR A1 - da Silva Mota, Fabio Antonio A1 - Hinckel, Jose Nivaldo A1 - Rocco, Evandro Marconi A1 - Schlingloff, Hanfried T1 - Trajectory Optimization of Launch Vehicles Using Object-oriented Programming JF - Journal of aerospace technology and management N2 - The aim of this study is to model launch vehicles with focus on 3-DOF trajectory optimization using a modular approach. Despite the large number of operational launch vehicles, they usually consist of basic components and subsystems. In other words, a launch vehicle is an assembly of stages, which in turn is divided into propellant system and engine, and the engine is an assembly of basic components such as pumps, turbines, combustion chamber, and nozzle. To allow future extension and reuse of the codes, a modular structure using object-oriented programming is used. Two formulations of state equations of the trajectory and two optimization methods are described. The launch vehicle performance will be measured by payload mass for a given mission. The simulations of the VLS-1, Ariane 5 and VLS-Alfa were performed and showed good agreement with the literature. KW - Launch vehicle KW - Object-oriented programming KW - Optimization KW - Trajectory Y1 - 2018 U6 - https://doi.org/10.5028/jatm.v10.948 VL - 10 PB - Institute of Aeronautics and Space ER - TY - JOUR A1 - Gärtner, Uwe A1 - Rabl, Hans-Peter A1 - Zink, Uwe T1 - Exhaust Gas Aftertreatment of the Future JF - MTZ worldwide Y1 - 2018 U6 - https://doi.org/10.1007/s38313-018-0060-2 VL - 79 IS - 7-8 SP - 70 EP - 75 PB - Springer ER - TY - JOUR A1 - Schümann, Malte A1 - Morich, J. A1 - Kaufhold, Tobias 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 - Hackl, Andreas A1 - Hirschberg, Wolfgang A1 - Lex, Cornelia 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 -