TY - CHAP A1 - Conti, Fosca A1 - Liu, E A1 - Bhogaraju, Sri Krishna A1 - Wunderle, Bernhard A1 - Elger, Gordon T1 - Finite Element simulations and Raman measurements to investigate thermomechanical stress in GaN-LEDs T2 - 2020 IEEE 8th Electronics System-Integration Technology Conference (ESTC) UR - https://doi.org/10.1109/ESTC48849.2020.9229843 KW - finite element method KW - gallium nitride (GaN) KW - LED KW - Raman spectroscopy KW - semiconductor KW - thermomechanical stress Y1 - 2020 UR - https://doi.org/10.1109/ESTC48849.2020.9229843 SN - 978-1-7281-6293-5 PB - IEEE CY - Piscataway ER - TY - CHAP A1 - Kühn, Stephan A1 - Pandey, Amit A1 - Zippelius, Andreas A1 - Schneider, Klaus A1 - Erdogan, Hüseyin A1 - Elger, Gordon T1 - Analysis of package design of optic modules for automotive cameras to realize reliable image sharpness T2 - 2020 IEEE 8th Electronics System-Integration Technology Conference (ESTC) UR - https://doi.org/10.1109/ESTC48849.2020.9229786 KW - Condition Monitoring KW - Health Indicator KW - Change in Sharpness KW - Through Focus Y1 - 2020 UR - https://doi.org/10.1109/ESTC48849.2020.9229786 SN - 978-1-7281-6293-5 PB - IEEE CY - Piscataway ER - TY - JOUR A1 - Hanzl, Christian A1 - Hartmann, Christoph A1 - Hölzle, Markus A1 - Liebhart, Bernhard A1 - Schmid, Michael A1 - Endisch, Christian T1 - Current commutation in a switched lithium-ion cell used in cascaded half-bridge multilevel inverters JF - IET Power Electronics N2 - In order to improve the efficiency of battery electric vehicles, the utilization of reconfigurable batteries and multilevel inverters based on low-voltage Si MOSFETs gains growing attention. Focusing on the half-bridge as basic switching unit, this paper examines voltage and current waveforms during switching. It is shown that the current commutation speed depends on various factors such as sign and amplitude of the current as well as the particular switching scenario. For instance, turning off a positive cell current takes 0.21 𝜇s while turning it on takes 0.9 𝜇s. In addition, it is revealed that depending on the switching scenario and current direction, the lithium-ion cell supports or opposes the remagnetization of the parasitic inductances and therefore the switching losses of the MOSFETs. Switching a positive load current of 125 A from active to bypass converts 276 𝜇J into heat while switching from bypass to active converts merely 32.5 𝜇J into heat. UR - https://doi.org/10.1049/pel2.12088 Y1 - 2021 UR - https://doi.org/10.1049/pel2.12088 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-13364 SN - 1755-4543 VL - 14 IS - 6 SP - 1073 EP - 1088 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Schmid, Michael A1 - Kneidinger, Hans-Georg A1 - Endisch, Christian T1 - Data-driven fault diagnosis in battery systems through cross-cell monitoring JF - IEEE Sensors Journal UR - https://doi.org/10.1109/JSEN.2020.3017812 KW - Battery systems KW - data-driven fault diagnosis KW - fault isolation KW - recursive principal component analysis KW - signal processing Y1 - 2020 UR - https://doi.org/10.1109/JSEN.2020.3017812 SN - 1558-1748 SN - 1530-437X SN - 2379-9153 VL - 21 IS - 2 SP - 1829 EP - 1837 PB - IEEE CY - New York ER - TY - CHAP A1 - Kleiner, Jan A1 - Heider, Alexander A1 - Hanzl, Christian A1 - Komsiyska, Lidiya A1 - Elger, Gordon A1 - Endisch, Christian T1 - Thermal behavior of an intelligent li-ion cell under vehicle conditions T2 - Proceedings: IECON 2020 The 46th Annual Conference of the IEEE Industrial Electronics Society UR - https://doi.org/10.1109/IECON43393.2020.9254336 KW - Li-ion KW - electro-thermal model KW - intelligent battery KW - reconfigurable system KW - smart cell Y1 - 2020 UR - https://doi.org/10.1109/IECON43393.2020.9254336 SN - 978-1-7281-5414-5 SN - 2577-1647 SP - 2081 EP - 2086 PB - IEEE CY - Piscataway ER - TY - JOUR A1 - Sequeira, Gerald Joy A1 - Brandmeier, Thomas T1 - Evaluation and characterization of crash-pulses for head-on collisions with varying overlap crash scenarios JF - Transportation Research Procedia N2 - Activation time for activating the occupant restraint systems (airbag and seatbelt) is very critical for an optimal safety action. A crash-pulse is the deceleration of the vehicle measured during in a crash. The shape, slope, maximum deceleration and duration of the crash-pulse provides significant information over the nature of occupant motions during in-crash phase and hence the crash severity. The above parameters of the crash-pulse not only depend on the mass and impact velocity but also on the crash configuration (position of impact, overlap, relative approach angle etc.). This study focuses on analysis and characterization of crash-pulses in head-on collision cases with varying overlap configurations. The paper describes causes for occupant injuries during a crash, crash-pulse and its important physical parameters, and different methodologies used to analyse the crash-pulse. Finite element simulation method is used to study the crash-pulses from different crash configurations. A new severity index that has direct influence on the occupant kinematics is defined. The results show that the steep decrease of crash-pulse for small overlap configurations (less than 25 percent of vehicle width) lags by 20 to 25 milliseconds as compared to configurations with large overlaps. The shape of the crash-pulse also changes for crash scenarios with different overlap configurations. The results, discussion and conclusion sections of this paper provide a summary of crash behaviour of varying overlap crash scenarios and insights that can be used for deployment of restraint systems. UR - https://doi.org/10.1016/j.trpro.2020.08.156 KW - Crash severity KW - Head-on collision KW - Frontal crash KW - Crash-pulse characterization Y1 - 2020 UR - https://doi.org/10.1016/j.trpro.2020.08.156 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-13319 SN - 2352-1465 VL - 2020 IS - 48 SP - 1306 EP - 1315 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Schmid, Maximilian A1 - Bhogaraju, Sri Krishna A1 - Elger, Gordon T1 - Characterization of copper sintered interconnects by transient thermal analysis T2 - 2021 International Conference on Electronics Packaging (ICEP 2021) UR - https://doi.org/10.23919/ICEP51988.2021.9451966 KW - copper sintering KW - transient thermal analysis (TTA) KW - thermal impedance (Zth) KW - non-destructive testing (NDT) KW - scanning acoustic microscopy (SAM) Y1 - 2021 UR - https://doi.org/10.23919/ICEP51988.2021.9451966 SN - 978-4-9911-9111-4 SP - 71 EP - 72 PB - IEEE CY - Piscataway ER - TY - CHAP A1 - Bhogaraju, Sri Krishna A1 - Schmid, Maximilian A1 - Hufnagel, Elias A1 - Conti, Fosca A1 - Kotadia, Hiren R. A1 - Elger, Gordon T1 - Low temperature and low pressure die-attach bonding of high power light emitting diodes with self reducing copper complex paste T2 - IEEE 71st Electronic Components and Technology Conference ECTC 2021, Proceedings UR - https://doi.org/10.1109/ECTC32696.2021.00094 KW - low temperature sintering KW - rapid sintering KW - Cu(II) formate KW - reducing binder KW - low pressure sintering KW - high bond strength Y1 - 2021 UR - https://doi.org/10.1109/ECTC32696.2021.00094 SN - 978-1-6654-4097-4 SP - 526 EP - 531 PB - IEEE CY - Piscataway ER - TY - CHAP A1 - Pascucci, Jacopo A1 - Conti, Fosca A1 - Bhogaraju, Sri Krishna A1 - Signorini, Raffaella A1 - Liu, E A1 - Pedron, Danilo A1 - Elger, Gordon ED - Cheben, Pavel ED - Čtyroký, Jiří ED - Molina-Fernández, Iñigo T1 - Micro-Raman to detect stress phenomena in Si-chips bonded onto Cu substrates T2 - Integrated Optics: Design, Devices, Systems and Applications VI UR - https://doi.org/10.1117/12.2576414 Y1 - 2021 UR - https://doi.org/10.1117/12.2576414 SN - 978-1-5106-4385-7 N1 - Poster + Paper PB - SPIE CY - Bellingham ER - TY - CHAP A1 - Conti, Fosca A1 - Lux, Kerstin A1 - Bhogaraju, Sri Krishna A1 - Liu, E A1 - Lenz, Christoph A1 - Seitz, Roland A1 - Elger, Gordon ED - Baldini, Francesco ED - Homola, Jiri ED - Lieberman, Robert A. T1 - Raman spectroscopy to investigate gallium nitride light emitting diodes after assembling onto copper substrates T2 - Optical Sensors 2021 UR - https://doi.org/10.1117/12.2591947 Y1 - 2021 UR - https://doi.org/10.1117/12.2591947 SN - 978-1-5106-4379-6 N1 - Poster + Paper PB - SPIE CY - Bellingham ER - TY - CHAP A1 - Tavakolibasti, M. A1 - Meszmer, P. A1 - Böttger, Gunnar A1 - Kettelgerdes, Marcel A1 - Elger, Gordon A1 - Erdogan, Hüseyin A1 - Seshaditya, A. A1 - Wunderle, Bernhard T1 - Thermo-mechanical-optical coupling within a digital twin development for automotive LiDAR T2 - 2021 22nd International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE) UR - https://doi.org/10.1109/EuroSimE52062.2021.9410831 KW - Couplings KW - Laser radar KW - Digital twin KW - Thermomechanical processes KW - Adaptive optics KW - Optical coupling KW - Real-time systems Y1 - 2021 UR - https://doi.org/10.1109/EuroSimE52062.2021.9410831 SN - 978-1-6654-1373-2 PB - IEEE CY - Piscataway ER - TY - CHAP A1 - Liu, E A1 - Conti, Fosca A1 - Bhogaraju, Sri Krishna A1 - Elger, Gordon T1 - Simulations and experiments to analyze stress phenomena in soldered and sintered interconnections between silicon nitride chips and copper substrates T2 - 2021 22nd International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE) UR - https://doi.org/10.1109/EuroSimE52062.2021.9410869 KW - Performance evaluation KW - Analytical models KW - Compressive stress KW - Thermomechanical processes KW - Data models KW - Microelectronics KW - Finite element analysis Y1 - 2021 UR - https://doi.org/10.1109/EuroSimE52062.2021.9410869 SN - 978-1-6654-1373-2 PB - IEEE CY - Piscataway ER - TY - CHAP A1 - Agrawal, Shiva A1 - Elger, Gordon T1 - Concept of infrastructure based environment perception for IN2Lab test field for automated driving T2 - 2021 IEEE International Smart Cities Conference (ISC2) UR - https://doi.org/10.1109/ISC253183.2021.9562894 KW - RSU KW - Radar KW - Lidar KW - Camera KW - Intelligent Infrastructure KW - Autonomous Driving KW - Sensor fusion Y1 - 2021 UR - https://doi.org/10.1109/ISC253183.2021.9562894 SN - 978-1-6654-4919-9 SN - 2687-8860 PB - IEEE CY - Piscataway ER - TY - JOUR A1 - Sequeira, Gerald Joy A1 - Patel, Akshay A1 - Afraj, Shahabaz A1 - Lugner, Robert A1 - Brandmeier, Thomas T1 - FEM-based methodology for crash severity estimation in frontal crash scenarios JF - IOP Conference Series: Materials Science and Engineering N2 - With the technological development of forward-looking sensors, researchers are exploring their use not only for advanced driver assistance systems but also to gain important pre-crash information. Based on this pre-crash information, if the occupant motion inside the vehicle structure can be predicted for the oncoming crash scenario, then an optimal restraint strategy can be planned before the crash. This paper introduces a two-step FEM simulation based methodology for predicting the occupant severity in head-on crash scenarios. In the first step, we simulate the vehicle level model with different impact positions and relative approach angles. The results of these simulations, linear velocities in the longitudinal and lateral direction and angular velocities (roll, pitch, and yaw) during in-crash phase are the loading conditions for next simulation step (occupant level). This step simulates the motion of the driver in different crash scenarios. In this paper, we investigate the head, neck, and chest injury risks from vehicle-to-vehicle crash both traveling at 50 kilometers per hour. Prediction of the head injury criterion, identifying the cases where additional deployment of side-airbags and discussion of injury criteria with contour plots are the main outcome of this paper. UR - https://doi.org/10.1088/1757-899X/831/1/012019 Y1 - 2020 UR - https://doi.org/10.1088/1757-899X/831/1/012019 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-13159 SN - 1757-899X SN - 1757-8981 VL - 2020 IS - 831 PB - IOP CY - Bristol ER - TY - JOUR A1 - Geisbauer, Christian A1 - Wöhrl, Katharina A1 - Lott, Susanne A1 - Nebl, Christoph A1 - Schweiger, Hans-Georg A1 - Goertz, Roland A1 - Kubjatko, Tibor T1 - Scenarios involving accident-damaged electric vehicles JF - Transportation Research Procedia N2 - Electrically propelled cars will play a major role on the streets, not only in the far, but also in the near future. In this work, an overview on the possible risks arising from electric vehicles is given that involves electrical, chemical and thermal hazards. Additionally, an analysis on different scenarios involving damaged electric vehicles, the involved parties, as well as their risk assessment in terms of hazard rating is presented. Furthermore, two scenarios are explained and addressed with more detail. With the derived risks of the battery and with possible crash scenarios presented, the still existing uncertainties for handling damaged electric vehicles are addressed, followed by a discussion on ways to overcome this problem. UR - https://doi.org/10.1016/j.trpro.2021.07.136 KW - electromobility KW - batteries KW - lithium ion KW - electric vehicle KW - accident KW - rescue service KW - recycling Y1 - 2021 UR - https://doi.org/10.1016/j.trpro.2021.07.136 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-13130 SN - 2352-1465 VL - 2021 IS - 55 SP - 1484 EP - 1489 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Ritz, Fabian A1 - Ratke, Daniel A1 - Phan, Thomy A1 - Belzner, Lenz A1 - Linnhoff-Popien, Claudia T1 - A sustainable ecosystem through emergent cooperation in multi-agent reinforcement learning T2 - Proceedings of the Artificial Life Conference 2021 UR - https://doi.org/10.1162/isal_a_00399 Y1 - 2021 UR - https://doi.org/10.1162/isal_a_00399 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-12975 VL - 2021 PB - MIT Press CY - Cambridge ER - TY - JOUR A1 - Mayer, Sebastian A1 - Classen, Tobias A1 - Endisch, Christian T1 - Modular production control using deep reinforcement learning: proximal policy optimization JF - Journal of Intelligent Manufacturing N2 - EU regulations on CO2 limits and the trend of individualization are pushing the automotive industry towards greater flexibility and robustness in production. One approach to address these challenges is modular production, where workstations are decoupled by automated guided vehicles, requiring new control concepts. Modular production control aims at throughput-optimal coordination of products, workstations, and vehicles. For this np-hard problem, conventional control approaches lack in computing efficiency, do not find optimal solutions, or are not generalizable. In contrast, Deep Reinforcement Learning offers powerful and generalizable algorithms, able to deal with varying environments and high complexity. One of these algorithms is Proximal Policy Optimization, which is used in this article to address modular production control. Experiments in several modular production control settings demonstrate stable, reliable, optimal, and generalizable learning behavior. The agent successfully adapts its strategies with respect to the given problem configuration. We explain how to get to this learning behavior, especially focusing on the agent’s action, state, and reward design. UR - https://doi.org/10.1007/s10845-021-01778-z KW - modular production KW - production control KW - production scheduling KW - deep reinforcement learning KW - proximal policy optimization KW - automotive industry Y1 - 2021 UR - https://doi.org/10.1007/s10845-021-01778-z UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-13092 SN - 1572-8145 VL - 32 IS - 8 SP - 2335 EP - 2351 PB - Springer Nature CY - Cham ER - TY - JOUR A1 - Theiler, Michael A1 - Endisch, Christian A1 - Lewerenz, Meinert T1 - Float Current Analysis for Fast Calendar Aging Assessment of 18650 Li(NiCoAl)O2/Graphite Cells JF - Batteries N2 - Float currents are steady-state self-discharge currents after a transient phase—caused by anode overhang, polarization, etc.—is accomplished. The float current is measured in this study with a standard test bench for five 18650 cells (Samsung 25R) at potentiostatic conditions while the temperature is changed in 5 K steps from 5 °C to 60 °C. The entire test is performed in about 100 days resulting in 12 measurement points per cell potential for an Arrhenius representation. The float current follows the Arrhenius law with an activation energy of about 60 kJ/mol. The capacity loss measured at reference condition shows a high correlation to the results of float currents analysis. In contrast to classical calendar aging tests, the performed float current analysis enables determining the aging rate with high precision down to at least 10 °C. Returning from higher temperatures to 30 °C reference temperature shows reducing float currents at 30 °C for increasing temperature steps that may originate from an hysteresis effect that has to be investigated in future publications. UR - https://doi.org/10.3390/batteries7020022 KW - 18650 KW - NCA KW - graphite KW - float current KW - self-discharge KW - calendar aging KW - Arrhenius Y1 - 2021 UR - https://doi.org/10.3390/batteries7020022 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-13081 SN - 2313-0105 VL - 7 IS - 2 PB - MDPI CY - Basel ER - TY - CHAP A1 - Unold, Florian von A1 - Wintergerst, Monika A1 - Belzner, Lenz A1 - Groh, Georg T1 - DYME: a dynamic metric for dialog modeling learned from human conversations T2 - Neural Information Processing: 28th International Conference, ICONIP 2021, Sanur, Bali, Indonesia, December 8–12, 2021, Proceedings, Part V UR - https://doi.org/10.1007/978-3-030-92307-5_30 KW - Dialog modeling KW - Conversational metrics KW - Dialog systems KW - Natural language processing Y1 - 2021 UR - https://doi.org/10.1007/978-3-030-92307-5_30 SN - 978-3-030-92307-5 SP - 257 EP - 264 PB - Springer CY - Cham ER - TY - JOUR A1 - Kleiner, Jan A1 - Stuckenberger, Magdalena A1 - Komsiyska, Lidiya A1 - Endisch, Christian T1 - Advanced monitoring and prediction of the thermal state of intelligent battery cells in electric vehicles by physics-based and data-driven modeling JF - Batteries N2 - Novel intelligent battery systems are gaining importance with functional hardware on the cell level. Cell-level hardware allows for advanced battery state monitoring and thermal management, but also leads to additional thermal interactions. In this work, an electro-thermal framework for the modeling of these novel intelligent battery cells is provided. Thereby, a lumped thermal model, as well as a novel neural network, are implemented in the framework as thermal submodels. For the first time, a direct comparison of a physics-based and a data-driven thermal battery model is performed in the same framework. The models are compared in terms of temperature estimation with regard to accuracy. Both models are very well suited to represent the thermal behavior in novel intelligent battery cells. In terms of accuracy and computation time, however, the data-driven neural network approach with a Nonlinear AutoregRessive network with eXogeneous input (NARX) shows slight advantages. Finally, novel applications of temperature prediction in battery electric vehicles are presented and the applicability of the models is illustrated. Thereby, the conventional prediction of the state of power is extended by simultaneous temperature prediction. Additionally, temperature forecasting is used for pre-conditioning by advanced cooling system regulation to enable energy efficiency and fast charging. UR - https://doi.org/10.3390/batteries7020031 KW - lithium-ion battery KW - electro-thermal model KW - smart cell KW - intelligent battery KW - neural network KW - temperature prediction Y1 - 2021 UR - https://doi.org/10.3390/batteries7020031 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-13068 SN - 2313-0105 VL - 7 IS - 2 PB - MDPI CY - Basel ER - TY - CHAP A1 - Brunner, Pascal A1 - Denk, Florian A1 - Huber, Werner A1 - Kates, Ronald T1 - Virtual safety performance assessment for automated driving in complex urban traffic scenarios T2 - 2019 IEEE Intelligent Transportation Systems Conference (ITSC) UR - https://doi.org/10.1109/ITSC.2019.8917517 Y1 - 2019 UR - https://doi.org/10.1109/ITSC.2019.8917517 SN - 978-1-5386-7024-8 SP - 679 EP - 685 PB - IEEE CY - Piscataway ER - TY - CHAP A1 - Denk, Florian A1 - Huber, Werner A1 - Brunner, Pascal A1 - Kates, Ronald T1 - The role of perceptual failure and degrading processes in urban traffic accidents: a stochastic computational model for virtual experiments T2 - 2020 IEEE 23rd International Conference on Intelligent Transportation Systems (ITSC) UR - https://doi.org/10.1109/ITSC45102.2020.9294498 KW - accidents KW - vehicles KW - safety KW - roads KW - computational modeling KW - stochastic processes KW - information processing Y1 - 2020 UR - https://doi.org/10.1109/ITSC45102.2020.9294498 SN - 978-1-7281-4149-7 PB - IEEE CY - Piscataway ER - TY - CHAP A1 - Brunner, Pascal A1 - Löcken, Andreas A1 - Denk, Florian A1 - Kates, Ronald A1 - Huber, Werner T1 - Analysis of experimental data on dynamics and behavior of e-scooter riders and applications to the impact of automated driving functions on urban road safety T2 - 2020 IEEE Intelligent Vehicles Symposium (IV) UR - https://doi.org/10.1109/IV47402.2020.9304835 KW - Safety KW - Accidents KW - Vehicle dynamics KW - Testing KW - Stability analysis KW - Motorcycles KW - Biological system modeling Y1 - 2021 UR - https://doi.org/10.1109/IV47402.2020.9304835 SN - 978-1-7281-6673-5 SP - 219 EP - 225 PB - IEEE CY - Piscataway ER - TY - CHAP A1 - Wurst, Jonas A1 - Balasubramanian, Lakshman A1 - Botsch, Michael A1 - Utschick, Wolfgang T1 - Novelty Detection and Analysis of Traffic Scenario Infrastructures in the Latent Space of a Vision Transformer-Based Triplet Autoencoder T2 - 2021 IEEE Intelligent Vehicles Symposium (IV) UR - https://doi.org/10.1109/IV48863.2021.9575730 Y1 - 2021 UR - https://doi.org/10.1109/IV48863.2021.9575730 SN - 978-1-7281-5394-0 SP - 1304 EP - 1311 PB - IEEE CY - Piscataway ER - TY - JOUR A1 - Schmid, Maximilian A1 - Bhogaraju, Sri Krishna A1 - Liu, E A1 - Elger, Gordon T1 - Comparison of Nondestructive Testing Methods for Solder, Sinter, and Adhesive Interconnects in Power and Opto-Electronics JF - Applied Sciences N2 - Reliability is one of the major requirements for power and opto-electronic devices across all segments. High operation temperature and/or high thermomechanical stress cause defects and degradation of materials and interconnects, which may lead to malfunctions with costly or even life-threatening consequences. To avoid or at least reduce failures, nondestructive testing (NDT) methods are common within development and production of power and opto-electronics. Currently, the dominating NDT methods are X-ray, scanning acoustic microscopy (SAM), and transient thermal analysis (TTA). However, they have different strengths and weaknesses with respect to materials and mechanical designs. This paper compares these NDT methods for different interconnect technologies, i.e., reflow soldering, adhesive, and sintered interconnection. While X-ray provided adequate results for soldered interfaces, inspection of adhesives and sintered interconnects was not possible. With SAM, evaluation of adhesives and sintered interconnects was also feasible, but quality depended strongly on the sample under test. TTA enabled sufficiently detailed results for all the interconnect applications. Automated TTA equipment, as the in-house developed tester used within this investigation, enabled measurement times compatible with SAM and X-ray. In the investigations, all methods revealed their pros and cons, and their selection has to depend on the sample under tests and the required analysis depth and data details. In the paper, guidelines are formulated for an appropriate decision on the NDT method depending on sample and requirements. UR - https://doi.org/10.3390/app10238516 KW - reliability KW - nondestructive testing KW - power electronics KW - X-ray KW - scanning acoustic microscopy KW - transient thermal analysis KW - TTA KW - sintering KW - LED KW - MOSFET Y1 - 2020 UR - https://doi.org/10.3390/app10238516 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-12518 SN - 2076-3417 VL - 10 IS - 23 PB - MDPI CY - Basel ER - TY - JOUR A1 - Schmid, Maximilian A1 - Bhogaraju, Sri Krishna A1 - Hanss, Alexander A1 - Elger, Gordon T1 - A new noise-suppression algorithm for transient thermal analysis in semiconductors over pulse superposition JF - IEEE Transactions on Instrumentation and Measurement UR - https://doi.org/10.1109/TIM.2020.3011818 KW - LED KW - linear time-invariant (LTI) system KW - MOSFET KW - noise suppression KW - reliability KW - semiconductor KW - signal processing KW - thermal impedance (Zth) KW - transient thermal analysis (TTA) Y1 - 2021 UR - https://doi.org/10.1109/TIM.2020.3011818 SN - 0018-9456 VL - 70 PB - IEEE CY - New York ER - TY - THES A1 - Hasnain, Syed Gazanfar T1 - Design and construction of a dynamically scaled vehicle for emergency scenario algorithm development N2 - Through the application of the Buckingham Pi theorem, a full-sized vehicle is scaled to create a model vehicle that is both geometrically and dynamically similar. The full-sized vehicle is systematically divided into three distinct sections, which are scaled independently. Each section is first described by an equivalent model to which the Buckingham Pi theorem is applied. The results of the scaling process define the design constraints that must be adhered to during the development of the equivalent scale model. Additional design constraints are added to the scaled vehicle to allow the final design to be flexible in its application and allow for a variety of experiments in subsequent research projects. The design constraints drive the selection of various components affecting the overall system layout. The final design is compared to the perfectly scaled model to determine their degree of similarity. Modifications are required on the final design to match the corresponding Pi groups of the perfectly scaled model. The modifications consist of redistributing the mass of the vehicle to minimize the deviations. Following the changes to the design, a physical model is constructed. The physical model consists of all the selected components and is built to develop and test vehicle control algorithms. The physical model is preliminarily validated against simulations to ensure that the longitudinal and lateral dynamics of the vehicle match those of the fully scaled vehicle. The ultimate goal of the scaled vehicle is to test emergency collision avoidance algorithms in a controlled environment and apply the findings to develop full-scale vehicle controllers in CARISSMA related projects. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-11707 CY - Ingolstadt ER - TY - THES A1 - Hartinger, Florian Xaver T1 - Machbarkeitsanalyse zur Auswertung von Iridium Bursts zur Stützung von Navigationssystemen N2 - Diese Machbarkeitsanalyse beschäftigt sich damit wie mithilfe gängiger Peilverfahren, aus den Signalen von Satelliten der Iridium Next Konstellation, Navigationsdaten zur Stützung von Navigationssystemen gewonnen werden können. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-11696 CY - Ingolstadt ER - TY - THES A1 - Fröhling, Felix Korbinian T1 - Evaluation of CNN-based object detection algorithms of thermal and color image sensors under adverse environment conditions N2 - Functional safety is becoming increasingly important in current ADAS systems, especially with technology facing an evolution as responsibility is gradually transferred from the driver to the car. The systems must perceive their environment correctly in any situation but sensors have their limitations. Thus, different sensor types must be combined to compensate the weakness of each sensor. The aim of this work is to find out whether thermal cameras have an added value for object detection in adverse environmental conditions such as rain, fog and different light conditions compared to conventional color cameras. To answer this question, three state-of-the-art algorithms for object detection on images based on neural networks are analyzed and compared. Current state-of-the-art algorithms are based on neural networks and need a large amount of labeled data. This data is generated using IPG CarMaker, a simulation tool, to simulate labeled color and thermal images. Besides synthetic data, also real sensor data is recorded in the CARISSMA test facility, where real adverse environmental conditions can be reproduced. This dataset is used for evaluation, i.e. by comparing the ground-truth data with the neural network predictions from the color and thermal images. With the evaluationdata statements can be done in which situations the algorithm is able to detect the object based on the color and thermal images and thereby what performance the algorithm achieves. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-11609 CY - Ingolstadt ER - TY - THES A1 - Finkler, Tim Christian T1 - Entwicklung und Umsetzung einer lernenden, kamerabasierten Roboteranlage zur Sortierung von Paletten N2 - Das Ziel der vorliegenden Arbeit ist es eine Roboteranlage zu entwickeln, die die Aufgabe der Sortierung und Stapelung von Europaletten übernehmen soll. Dazu wird eine ausführliche Recherche des bisherigen Prozesses und die Anforderungen des Unternehmens genau untersucht. Sobald die Ist-Situation genau definiert ist werden verschiedene Lösungsvarianten erarbeitet. Die Auswahl der Komponenten, wie z.B. der Roboter, der Effektor und das Kamerasystem werden genau evaluiert. Dies führt anschließend zu einem umfassenden Gesamtkonzept. In Form eines Prototyps wird ein Großteil des Gesamtkonzepts umgesetzt. Um die Roboteranlage im Anschluss fertigzustellen, werden die einzelnen Schritte dokumentiert. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-11574 CY - Ingolstadt ER - TY - THES A1 - Aydin, Serkan T1 - Comparative measurements on lithium-ion batteries for RC equivalent circuit modelling N2 - This master thesis aims to perform different measurements on Lithium ion (Li-ion) batteries containing different cell chemistries by changing the temperature, State of Charge (SoC), and C-Rate variables. First, extensive research was conducted on what type of lithium-ion batteries should be used, and also different test sequences and a test plan were created that takes into account the characteristics of the batteries and other conditions that will affect the experiments. Next, the equipment that should be used for the experiments was selected and examined. After equipment selection, the battery tester, which played the most crucial role in this project, was tested with various batteries, and the results of these tests were deeply analyzed. Then, a wooden rig has been created for the experiments, which holds the battery in the temperature chamber while testing. This was a critical step because the connections of the batteries were not supposed to be disconnected during the experiments. Finally, after the tests were completed, internal resistance and single RC equivalent circuit model elements calculated with different methods by using Matlab scripts and these results are presented in this thesis with various graphs. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-11175 CY - Ingolstadt ER - TY - JOUR A1 - Kotak, Bhavya A1 - Kotak, Yash A1 - Brade, Katja A1 - Kubjatko, Tibor A1 - Schweiger, Hans-Georg T1 - Battery Crush Test Procedures in Standards and Regulation: Need for Augmentation and Harmonisation JF - Batteries N2 - Battery safety is a prominent concern for the deployment of electric vehicles (EVs). The battery powering an EV contains highly energetic active materials and flammable organic electrolytes. Usually, an EV battery catches fire due to its thermal runaway, either immediately at the time of the accident or can take a while to gain enough heat to ignite the battery chemicals. There are numerous battery abuse testing standards and regulations available globally. Therefore, battery manufacturers are always in dilemma to choose the safest one. Henceforth, to find the optimal outcome of these two major issues, six standards (SAE J2464:2009, GB/T 31485-2015:2015, FreedomCAR:2006, ISO 12405-3:2014, IEC 62660-2:2010, and SAND2017-6295:2017) and two regulations (UN/ECE-R100.02:2013 and GTR 20:2018), that are followed by more than fifty countries in the world, are investigated in terms of their abuse battery testing conditions (crush test). This research proves that there is a need for (a) augmenting these standards and regulations as they do not consider real-life vehicle crash scenarios, and (b) one harmonised framework should be developed, which can be adopted worldwide. These outcomes will solve the battery manufacturers dilemma and will also increase the safety of EV consumers. UR - https://doi.org/10.3390/batteries7030063 KW - lithium-ion battery KW - electric vehicle battery KW - battery standard KW - battery regulation KW - battery testing standard KW - battery testing regulation KW - abuse testing KW - harmonising battery standard KW - crush test procedure KW - battery incidents KW - battery standard and regulation augmentation Y1 - 2021 UR - https://doi.org/10.3390/batteries7030063 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-11083 SN - 2313-0105 VL - 7 IS - 3 PB - MDPI CY - Basel ER - TY - JOUR A1 - Sánchez Morales, Eduardo A1 - Dauth, Julian A1 - Huber, Bertold A1 - García Higuera, Andrés A1 - Botsch, Michael T1 - High precision outdoor and indoor reference state estimation for testing autonomous vehicles JF - Sensors N2 - A current trend in automotive research is autonomous driving. For the proper testing and validation of automated driving functions a reference vehicle state is required. Global Navigation Satellite Systems (GNSS) are useful in the automation of the vehicles because of their practicality and accuracy. However, there are situations where the satellite signal is absent or unusable. This research work presents a methodology that addresses those situations, thus largely reducing the dependency of Inertial Navigation Systems (INSs) on the SatNav. The proposed methodology includes (1) a standstill recognition based on machine learning, (2) a detailed mathematical description of the horizontation of inertial measurements, (3) sensor fusion by means of statistical filtering, (4) an outlier detection for correction data, (5) a drift detector, and (6) a novel LiDAR-based Positioning Method (LbPM) for indoor navigation. The robustness and accuracy of the methodology are validated with a state-of-the-art INS with Real-Time Kinematic (RTK) correction data. The results obtained show a great improvement in the accuracy of vehicle state estimation under adverse driving conditions, such as when the correction data is corrupted, when there are extended periods with no correction data and in the case of drifting. The proposed LbPM method achieves an accuracy closely resembling that of a system with RTK. UR - https://doi.org/10.3390/s21041131 KW - machine learning KW - autonomous vehicles KW - Inertial Navigation System KW - Satellite Navigation KW - Real-Time Kinematic KW - indoor navigation KW - reference state Y1 - 2021 UR - https://doi.org/10.3390/s21041131 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10932 SN - 1424-8220 N1 - "This paper is an extended version of our paper published in : Sánchez Morales, E.; Botsch, M.; Huber, B.; García Higuera, A. High precision indoor positioning by means of LiDAR. In Proceedings of the 2019 DGON Inertial Sensors and Systems (ISS), Braunschweig, Germany, 10–11 September 2019." VL - 21 IS - 4 PB - MDPI CY - Basel ER - TY - JOUR A1 - Schneider, Dominik A1 - Vögele, Ulrich A1 - Endisch, Christian T1 - Model-based sensor data fusion of quasi-redundant voltage and current measurements in a lithium-ion battery module JF - Journal of Power Sources UR - https://doi.org/10.1016/j.jpowsour.2019.227156 KW - Battery model KW - Current sensor KW - Dual kalman filter KW - Sensor data fusion KW - State estimation KW - Weighted least squares Y1 - 2019 UR - https://doi.org/10.1016/j.jpowsour.2019.227156 SN - 1873-2755 VL - 2019 IS - 440 PB - Elsevier CY - New York ER - TY - JOUR A1 - Liebhart, Bernhard A1 - Komsiyska, Lidiya A1 - Endisch, Christian T1 - Passive impedance spectroscopy for monitoring lithium-ion battery cells during vehicle operation JF - Journal of Power Sources UR - https://doi.org/10.1016/j.jpowsour.2019.227297 KW - (Nonparametric) system identification KW - (Passive) impedance spectroscopy KW - Data-driven battery parameter estimation KW - Single-cell BMS Y1 - 2019 UR - https://doi.org/10.1016/j.jpowsour.2019.227297 SN - 1873-2755 VL - 2020 IS - 449 PB - Elsevier CY - New York ER - TY - JOUR A1 - Schmid, Michael A1 - Vögele, Ulrich A1 - Endisch, Christian T1 - A novel matrix-vector-based framework for modeling and simulation of electric vehicle battery packs JF - Journal of Energy Storage UR - https://doi.org/10.1016/j.est.2020.101736 KW - Electric vehicle KW - Lithium-ion battery pack KW - Control-oriented modeling KW - Electro-thermal model KW - Fault diagnosis KW - Performance analysis Y1 - 2020 UR - https://doi.org/10.1016/j.est.2020.101736 SN - 2352-1538 VL - 2020 IS - 32 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Liebhart, Bernhard A1 - Satzke, Martin A1 - Komsiyska, Lidiya A1 - Endisch, Christian T1 - Application of nonlinear impedance spectroscopy for the diagnosis of lithium-ion battery cells under various operating conditions JF - Journal of Power Sources UR - https://doi.org/10.1016/j.jpowsour.2020.228673 KW - Nonlinear impedance spectroscopy KW - Mechanical pressure KW - Frequency response functions KW - Volterra kernels Y1 - 2020 UR - https://doi.org/10.1016/j.jpowsour.2020.228673 SN - 1873-2755 VL - 2020 IS - 480 PB - Elsevier CY - New York ER - TY - JOUR A1 - Geisbauer, Christian A1 - Wöhrl, Katharina A1 - Mittmann, Christoph A1 - Schweiger, Hans-Georg T1 - Review of Safety Aspects of Calendar Aged Lithium Ion Batteries JF - Journal of the Electrochemical Society N2 - Nowadays, lithium ion batteries have found their place in a various field of portable applications. With the upcoming of electrically propelled vehicles, it is mandatory to guarantee a safe and predictable behavior during the whole lifetime and not only after manufacturing during performance tests. To gain a general overview of the abuse behavior, research on the topic of abusive tests on calendar-aged cells is being investigated, split up depending on the electrode composition and lined up against each other. It can be shown, that almost all abuse experiments have been performed with external heating tests in the past, still leaving research gaps that need to be filled. UR - https://doi.org/10.1149/1945-7111/ab89bf Y1 - 2020 UR - https://doi.org/10.1149/1945-7111/ab89bf UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10183 SN - 1945-7111 VL - 167 IS - 9 PB - IOP Publishing CY - Bristol ER - TY - JOUR A1 - Lausch, Jonas A1 - Takla, Monir A1 - Schweiger, Hans-Georg T1 - Crush testing approach for flat-plate fibrous materials JF - Composites Part B: Engineering UR - https://doi.org/10.1016/j.compositesb.2020.108333 KW - Plates KW - Mechanical properties KW - Impact behavior KW - Mechanical testing KW - Energy absorption Y1 - 2020 UR - https://doi.org/10.1016/j.compositesb.2020.108333 SN - 1879-1069 VL - 2020 IS - 200 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kostetzer, Lucas A1 - Nebl, Christoph A1 - Stich, Michael A1 - Bund, Andreas A1 - Schweiger, Hans-Georg T1 - Physics-Based Modeling and Parameter Identification for Lithium Ion Batteries Under High Current Discharge Conditions JF - Journal of the Electrochemical Society UR - https://doi.org/10.1149/1945-7111/abc726 Y1 - 2020 UR - https://doi.org/10.1149/1945-7111/abc726 SN - 1945-7111 VL - 167 IS - 14 PB - IOP Publishing CY - Bristol ER - TY - JOUR A1 - Ahlberg Tidblad, Annika A1 - Edström, Kristina A1 - Hernández, Guiomar A1 - de Meatza, Iratxe A1 - Landa-Medrano, Imanol A1 - Jacas Biendicho, Jordi A1 - Trilla, Lluís A1 - Buysse, Maarten A1 - Ierides, Marcos A1 - Perez Horno, Beatriz A1 - Kotak, Yash A1 - Schweiger, Hans-Georg A1 - Koch, Daniel A1 - Kotak, Bhavya T1 - Future Material Developments for Electric Vehicle Battery Cells Answering Growing Demands from an End-User Perspective JF - Energies N2 - Nowadays, batteries for electric vehicles are expected to have a high energy density, allow fast charging and maintain long cycle life, while providing affordable traction, and complying with stringent safety and environmental standards. Extensive research on novel materials at cell level is hence needed for the continuous improvement of the batteries coupled towards achieving these requirements. This article firstly delves into future developments in electric vehicles from a technology perspective, and the perspective of changing end-user demands. After these end-user needs are defined, their translation into future battery requirements is described. A detailed review of expected material developments follows, to address these dynamic and changing needs. Developments on anodes, cathodes, electrolyte and cell level will be discussed. Finally, a special section will discuss the safety aspects with these increasing end-user demands and how to overcome these issues. UR - https://doi.org/10.3390/en14144223 KW - electric vehicle KW - battery material KW - anode KW - cathode KW - electrolyte KW - battery safety KW - end-user demands Y1 - 2021 UR - https://doi.org/10.3390/en14144223 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10149 SN - 1996-1073 VL - 14 IS - 14 PB - MDPI CY - Basel ER - TY - JOUR A1 - Komsiyska, Lidiya A1 - Buchberger, Tobias A1 - Diehl, Simon A1 - Ehrensberger, Moritz A1 - Hanzl, Christian A1 - Hartmann, Christoph A1 - Hölzle, Markus A1 - Kleiner, Jan A1 - Lewerenz, Meinert A1 - Liebhart, Bernhard A1 - Schmid, Michael A1 - Schneider, Dominik A1 - Speer, Sascha A1 - Stöttner, Julia A1 - Terbrack, Christoph A1 - Hinterberger, Michael A1 - Endisch, Christian T1 - Critical review of intelligent battery systems BT - challenges, implementation, and potential for electric vehicles JF - Energies N2 - This review provides an overview of new strategies to address the current challenges of automotive battery systems: Intelligent Battery Systems. They have the potential to make battery systems more performant and future-proof for coming generations of electric vehicles. The essential features of Intelligent Battery Systems are the accurate and robust determination of cell individual states and the ability to control the current of each cell by reconfiguration. They enable high-level functions like fault diagnostics, multi-objective balancing strategies, multilevel inverters, and hybrid energy storage systems. State of the art and recent advances in these topics are compiled and critically discussed in this article. A comprising, critical discussion of the implementation aspects of Intelligent Battery Systems complements the review. We touch on sensing, battery topologies and management, switching elements, communication architecture, and impact on the single-cell. This review contributes to transferring the best technologies from research to product development. UR - https://doi.org/10.3390/en14185989 KW - smart battery KW - intelligent battery system KW - advanced monitoring KW - reconfigurable battery KW - battery management system KW - electric vehicle Y1 - 2021 UR - https://doi.org/10.3390/en14185989 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10132 SN - 1996-1073 VL - 14 IS - 18 PB - MDPI CY - Basel ER - TY - JOUR A1 - Wöhrl, Katharina A1 - Geisbauer, Christian A1 - Nebl, Christoph A1 - Lott, Susanne A1 - Schweiger, Hans-Georg T1 - Crashed Electric Vehicle Handling and Recommendations - State of the Art in Germany JF - Energies N2 - In the near future, electric powered vehicles will represent a major part of the road traffic. Accordingly, there will be a natural increase of accidents involving electric vehicles. There are not many cases of such accidents yet and therefore the experience and correct handling are still partially open points for the involved parties, such as the rescue services for example. The aim of this work is to provide a complete overview of the accident handling sequence in Germany, starting with the damaged vehicle on site and moving on to the risks and challenges for the stakeholders, such as transport and recycling companies. Arising from the developed overview, a handling recommendation for yet undiscussed points is given. Especially, different extinguishing and deactivation methods are compared and discussed. Due to a lack of a common live-feed from battery data on site, other criteria have to be taken into account to assess the state of the battery. The wrecked vehicle—including the high voltage system—needs to be in a definite safe state at the handover to a towing service. Depending on the case, different options for securing the vehicle will be considered in this work. UR - https://doi.org/10.3390/en14041040 KW - electric vehicle KW - battery KW - high voltage KW - accident KW - recommendation KW - energy storage KW - thermal runaway KW - fire extinguishing KW - rescue service KW - handling Y1 - 2021 UR - https://doi.org/10.3390/en14041040 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10123 SN - 1996-1073 VL - 14 IS - 4 PB - MDPI CY - Basel ER - TY - JOUR A1 - Kotak, Yash A1 - Marchante Fernández, Carlos A1 - Canals Casals, Lluc A1 - Kotak, Bhavya A1 - Koch, Daniel A1 - Geisbauer, Christian A1 - Trilla, Lluís A1 - Gómez-Nuñez, Alberto A1 - Schweiger, Hans-Georg T1 - End of Electric Vehicle Batteries BT - Reuse vs. Recycle JF - Energies N2 - It is a fact that electric vehicles (EVs) are beneficial for climate protection. However, the current challenge is to decide on whether to reuse an EV battery or to recycle it after its first use. This paper theoretically investigates these areas i.e., recycle and reuse. It was found that there are several commercially used recycling processes and also some are under research to regain maximum possible materials and quantity. The concept of reusing (second life) of the battery is promising because, at the end of the first life, batteries from EVs can be used in several applications such as storing energy generated from renewable sources to support the government grid. However, the cost and life-cycle analysis (LCA) demonstrated that there are several aspects involved in battery reuse applications. Henceforth, one LCA generalised method cannot provide an optimal approach for all cases. It is important to have a detailed study on each of the battery reusing applications. Until then, it is safe to say that reusing the battery is a good option as it would give some time to recycling companies to develop cost and energy-efficient methods. UR - https://doi.org/10.3390/en14082217 KW - battery recycling KW - battery reuse KW - battery second life KW - circular economy KW - lithium-ion cells KW - electric vehicles KW - battery components recycling KW - sustainability in mobility KW - battery safety KW - battery cost analysis Y1 - 2021 UR - https://doi.org/10.3390/en14082217 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10115 SN - 1996-1073 VL - 14 IS - 8 PB - MDPI CY - Basel ER - TY - JOUR A1 - Lausch, Jonas A1 - Takla, Monir A1 - Schweiger, Hans-Georg T1 - Crush characteristics of flat-plate discontinuous carbon composites JF - Composites Part A: Applied science and manufacturing UR - https://doi.org/10.1016/j.compositesa.2021.106431 Y1 - 2021 UR - https://doi.org/10.1016/j.compositesa.2021.106431 SN - 1359-835X VL - 147 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Geisbauer, Christian A1 - Wöhrl, Katharina A1 - Koch, Daniel A1 - Wilhelm, Gudrun A1 - Schneider, Gerhard A1 - Schweiger, Hans-Georg T1 - Comparative Study on the Calendar Aging Behavior of Six Different Lithium-Ion Cell Chemistries in Terms of Parameter Variation JF - Energies N2 - The degradation of lithium-ion cells is an important aspect, not only for quality management, but also for the customer of the application like, e.g., scooters or electric vehicles. During the lifetime of the system, the overall health on the battery plays a key role in its depreciation. Therefore, it is necessary to monitor the health of the battery during operation, i.e., cycle life, but also during stationary conditions, i.e., calendar aging. In this work, the degradation due to calendar aging is analyzed for six different cell chemistries in terms of capacity degradation and impedance increase and their performance are being compared. In a new proposed metric, the relative deviations between various cells with the exact identical aging history are being analyzed for their degradation effects and their differences, which stands out in comparison to similar research. The capacity loss was found to be most drastic at 60 °C and at higher storage voltages, even for titanate-oxide cells. LiNiMnCoO2 (NMC), LiNiCoAlO2 (NCA) and Li2TiO3 (LTO) cells at 60 °C showed the most drastic capacity decrease. NMC and NCA cells at 60 °C and highest storage voltage did not show any open circuit voltage, as their current interrupt mechanism triggered. The effect of aging shows no uniform impact on the changes in the capacity variance when comparing different aging conditions, with respect to the evaluated standard deviation for all cells. The focus of this work was on the calendar aging effect and may be supplemented in a second study for cyclic aging. UR - https://doi.org/10.3390/en14113358 KW - electromobility KW - batteries KW - lithium-ion KW - calendar aging KW - electric vehicle KW - capacity degradation KW - storage KW - parameter distribution Y1 - 2021 UR - https://doi.org/10.3390/en14113358 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10091 SN - 1996-1073 VL - 14 IS - 11 PB - MDPI CY - Basel ER - TY - JOUR A1 - Theissler, Andreas A1 - Pérez-Velázquez, Judith A1 - Kettelgerdes, Marcel A1 - Elger, Gordon T1 - Predictive maintenance enabled by machine learning: Use cases and challenges in the automotive industry JF - Reliability Engineering & System Safety N2 - Recent developments in maintenance modelling fuelled by data-based approaches such as machine learning (ML), have enabled a broad range of applications. In the automotive industry, ensuring the functional safety over the product life cycle while limiting maintenance costs has become a major challenge. One crucial approach to achieve this, is predictive maintenance (PdM). Since modern vehicles come with an enormous amount of operating data, ML is an ideal candidate for PdM. While PdM and ML for automotive systems have both been covered in numerous review papers, there is no current survey on ML-based PdM for automotive systems. The number of publications in this field is increasing — underlining the need for such a survey. Consequently, we survey and categorize papers and analyse them from an application and ML perspective. Following that, we identify open challenges and discuss possible research directions. We conclude that (a) publicly available data would lead to a boost in research activities, (b) the majority of papers rely on supervised methods requiring labelled data, (c) combining multiple data sources can improve accuracies, (d) the use of deep learning methods will further increase but requires efficient and interpretable methods and the availability of large amounts of (labelled) data. UR - https://doi.org/10.1016/j.ress.2021.107864 KW - predictive maintenance KW - artificial intelligence KW - machine learning KW - deep learning KW - vehicle KW - automotive KW - reliability KW - lifetime prediction KW - condition monitoring Y1 - 2021 UR - https://doi.org/10.1016/j.ress.2021.107864 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9673 SN - 0951-8320 VL - 2021 IS - 215 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Da Rosa Zanatta, Mateus A1 - Carvalho Lustosa da Costa, Joao Paulo A1 - Antreich, Felix A1 - Haardt, Martin A1 - Elger, Gordon A1 - Lopes de Mendonça, Fábio Lúcio A1 - de Sousa Junior, Rafael Timóteo T1 - Tensor-based framework with model order selection and high accuracy factor decomposition for time-delay estimation in dynamic multipath scenarios JF - IEEE Access N2 - Global Navigation Satellite Systems (GNSS) are crucial for applications that demand very accurate positioning. Tensor-based time-delay estimation methods, such as CPD-GEVD, DoA/KRF, and SECSI, combined with the GPS3 L1C signal, are capable of, significantly, mitigating the positioning degradation caused by multipath components. However, even though these schemes require an estimated model order, they assume that the number of multipath components is constant. In GNSS applications, the number of multipath components is time-varying in dynamic scenarios. Thus, in this paper, we propose a tensor-based framework with model order selection and high accuracy factor decomposition for time-delay estimation in dynamic multipath scenarios. Our proposed approach exploits the estimates of the model order for each slice by grouping the data tensor slices into sub-tensors to provide high accuracy factor decomposition. We further enhance the proposed approach by incorporating the tensor-based Multiple Denoising (MuDe). UR - https://doi.org/10.1109/ACCESS.2020.3024597 KW - Global navigation satellite systems (GNSS) KW - global positioning system (GPS) KW - GPS3 KW - time-delay estimation (TDE) KW - multipath components KW - model order selection (MOS) Y1 - 2020 UR - https://doi.org/10.1109/ACCESS.2020.3024597 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9528 SN - 2169-3536 VL - 8 SP - 174931 EP - 174942 PB - IEEE CY - New York ER - TY - JOUR A1 - Steger, Fabian A1 - Nitsche, Alexander A1 - Arbesmeier, Alexander A1 - Brade, Katja A1 - Schweiger, Hans-Georg A1 - Belski, Iouri T1 - Teaching Battery Basics in Laboratories: Hands-On Versus Simulated Experiments JF - IEEE Transactions on Education N2 - Contribution: Prior studies comparing the effectiveness of different laboratory learning modes do not allow one to draw a universally valid conclusion, as other influences are mixed with the learning modes. In order to contribute to the existing body of work and to add another piece to the puzzle, this article demonstrates an improved methodology to evaluate the effectiveness of computer-simulated laboratories in comparison to hands-on exercises using a battery basics practical course as a case study. Background: Computer-simulated experiments are becoming increasingly popular for conducting laboratory exercises in higher education and vocational training institutions. To ensure the consistent quality of laboratory learning, an accurate comparison between the results of simulated experiments and practical hands-on experiments is required. Intended Outcomes: In this article, the achievement of the following learning objectives were compared between the two laboratory modes: 1) comprehension of the most important parameters of battery cells and 2) knowledge on how these parameters can be determined using adequate experimental procedures. Application Design: To avoid interference of factors other than laboratory mode on the learning, laboratory instructions and experimental interfaces ensured identical execution of the experiments in the compared modes. Using a counterbalanced methodology, the two laboratory modes alternated by the session, while the experimental procedures remained constant regardless of the respective modes. Findings: Tests taken by the participants after conducting the laboratory experiments revealed that hands-on laboratories resulted in statistically significantly better student performance than simulated laboratories. This difference was even more pronounced for the participants that finished a vocational education and training program before the university studies. UR - https://doi.org/10.1109/TE.2020.2970554 KW - battery KW - electrical engineering KW - energy storages KW - hands-on KW - knowledge gain KW - laboratory learning KW - simulation KW - student experience Y1 - 2020 UR - https://doi.org/10.1109/TE.2020.2970554 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9517 SN - 1557-9638 VL - 63 IS - 3 SP - 198 EP - 208 PB - IEEE CY - Piscataway ER - TY - JOUR A1 - Liu, E A1 - Conti, Fosca A1 - Bhogaraju, Sri Krishna A1 - Signorini, Raffaella A1 - Pedron, Danilo A1 - Wunderle, Bernhard A1 - Elger, Gordon T1 - Thermomechanical stress in GaN-LEDs soldered onto Cu substrates studied using finite element method and Raman spectroscopy JF - Journal of Raman Spectroscopy N2 - Local thermomechanical stress can cause failures in semiconductor packages during long-time operation under harsh environmental conditions. This study helps to explain the packaging-induced stress in blue GaN-LEDs soldered onto copper substrates using AuSn alloy as lead-free interconnect material. Based on the finite element method, a virtual prototype is developed to simulate the thermomechanical behavior and stress in the LED and in the complete LED/AuSn/Cu assembly considering plastic and viscoplastic strain. The investigations were performed by varying the temperature between −50°C and 180°C. To validate the model, the simulation results are compared to experimental data collected with Raman spectroscopy. Studies of the urn:x-wiley:03770486:media:jrs5947:jrs5947-math-0003 phonon mode of GaN semiconductor are elaborated to understand the induced thermomechanical stress. The model enables evaluation of the stress in the interfaces of the assembly, which otherwise cannot be accessed by measurements. It serves to predict how assemblies would perform, before committing resources to build a physical prototype. UR - https://doi.org/10.1002/jrs.5947 KW - finite element method KW - gallium nitride (GaN) KW - LED KW - semiconductor KW - thermomechanical stress Y1 - 2020 UR - https://doi.org/10.1002/jrs.5947 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9438 SN - 1097-4555 VL - 51 IS - 10 SP - 2083 EP - 2094 PB - Wiley CY - Chichester ER - TY - JOUR A1 - Böhm, Klaus A1 - Kubjatko, Tibor A1 - Paula, Daniel A1 - Schweiger, Hans-Georg T1 - New developments on EDR (Event Data Recorder) for automated vehicles JF - Open Engineering N2 - With the upcoming new legislative rules in the EU on Event Data Recorder beginning 2022 the question is whether the discussed data base is sufficient for the needs of clarifying accidents involving automated vehicles. Based on the reconstruction of real accidents including vehicles with ADAS combined with specially designed crash tests a broader data base than US EDR regulation (NHTSA 49 CFR Part 563.7) is proposed. The working group AHEAD, to which the authors contribute, has already elaborated a data model that fits the needs of automated driving. The structure of this data model is shown. Moreover, the special benefits of storing internal video or photo feeds form the vehicle camera systems combined with object data is illustrated. When using a sophisticate 3D measurement method of the accident scene the videos or photos can also serve as a control instance for the stored vehicle data. The AHEAD Data Model enhanced with the storage of the video and photo feeds should be considered in the planned roadmap of the Informal Working Group (IWG) on EDR/ DSSAD (Data Storage System for Automated Driving) reporting to UNECE WP29. Also, a data access over the air using technology already applied in China for electric vehicles called Real Time Monitoring would allow a quantum leap in forensic accident reconstruction. UR - https://doi.org/10.1515/eng-2020-0007 KW - Event Data Recorder (EDR) KW - automated vehicles KW - video and photo feeds KW - Real Time Monitoring (RTM) KW - AHEAD (Aggregated Homologation proposal for Event data recorder for Automated Driving) Y1 - 2020 UR - https://doi.org/10.1515/eng-2020-0007 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9263 SN - 2391-5439 VL - 10 IS - 1 SP - 140 EP - 146 PB - De Gruyter CY - Berlin ER - TY - JOUR A1 - Nebl, Christoph A1 - Kotzur, Frank-Oliver A1 - Koch, Daniel A1 - Schweiger, Hans-Georg T1 - Prediction of constant power delivery of lithium-ion cells at high loads JF - Journal of Energy Storage N2 - Available energy and available capacity are key factors for dimensioning batteries. Discharge duration of a battery and its dependency on discharge current amplitude are well described by Peukert’s law from low to medium current ranges. Other equations describe this dependency up to very high current rates, including the currents occurring during a short circuit. It is not current and capacity, but energy and power which are the key parameters for dimensioning battery systems. Thus, the available power of battery cells, vs. the discharge duration was investigated from low to high constant power discharge loads. Based on the results of these experiments, a correlation of the maximum discharge duration for low to medium discharge power pulses, similar to the Peukert’s equation was found. Additionally, a new equation is proposed, describing the power range from low to very high discharge power rates. The result of this work simplifies the design of battery systems, its electromechanical components, as well as improves the prediction of available boost power cost-effective way e.g. for hybrid electric vehicles. UR - https://doi.org/10.1016/j.est.2020.101552 KW - Constant power discharge KW - Lithium-ion batteries KW - Peukert equation KW - High load amplitudes KW - Constant power prediction KW - Discharge power Y1 - 2020 UR - https://doi.org/10.1016/j.est.2020.101552 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9239 SN - 2352-1538 VL - 2020 IS - 30 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Shirur, Naveen A1 - Birkner, Christian A1 - Henze, Roman A1 - Deserno, Thomas Martin T1 - Tactile Occupant Detection Sensor for Automotive Airbag JF - Energies N2 - Automotive airbags protect occupants from crash forces during severe vehicle collisions. They absorb energy and restrain the occupants by providing a soft cushion effect known as the restraint effect. Modern airbags offer partial restraint effect control by controlling the bag’s vent holes and providing multi-stage deployment. Full restraint effect control is still a challenge because the closed-loop restraint control system needs airbag–occupant contact and interaction feedback. In this work, we have developed novel single and matrix capacitive tactile sensors to measure the occupant’s contact data. They can be integrated with the airbag surface and folded to follow the dynamic airbag shape during the deployment. The sensors are tested under a low-velocity pendulum impact and benchmarked with high-speed test videos. The results reveal that the single sensor can successfully measure occupant–airbag contact time and estimate the area, while the contact position is additionally identified from the matrix sensor. UR - https://doi.org/10.3390/en14175288 KW - automotive airbag KW - capacitive tactile sensor KW - occupant detection KW - passive safety KW - vehicle crash Y1 - 2021 UR - https://doi.org/10.3390/en14175288 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-9210 SN - 1996-1073 VL - 14 IS - 17 PB - MDPI CY - Basel ER - TY - THES A1 - Ballal, Niranjan T1 - Analysis of numerical crash simulation data using dimensionality reduction and machine learning N2 - Automakers find it challenging to analyze multiple computer-based numerical crash simulation data, with an increase in computer-based simulations. This downside causes the necessity to use data science techniques to automate the analysis of an ensemble of crash simulation data. This study aims at setting up a workflow to dimensionally reduce the simulation data, cluster it based on a behavioral pattern and analyze a particular behavioral pattern to obtain if-else rules to avoid or achieve that particular behavioral pattern. In this context, a behavioral pattern refers to an observed characteristic result that occurs because of specific input parameter values. In this thesis, dimensionality reduction is undertaken using feature extraction algorithms, the knowledge behind the simulations is extracted and clustered based on an individual simulation’s behavioral pattern using unsupervised clustering algorithms, and the rules to avoid or achieve a particular behavioral pattern are extracted using decision tree algorithm and associative rule mining algorithm. The workflow is applied to a simple side pole impact test, where a pole is impacted to an assembly of three parallel vertical members welded to a horizontal member. Using the workflow, every simulation data is represented using 50 lower-dimensional parameters and the simulations in the dataset are clustered into three different clusters based on three different behavioral patterns observed. One of the behavioral patterns observed is lower buckling of a vertical member, which is not a desired crash behavior to be observed in a crash energy absorption structure and this behavior should be avoided. The rules to avoid this behavioral pattern is further obtained using rule extraction. The results from the study suggest that the workflow and the algorithms used in this thesis to analyze an ensemble of simulation data helps an engineer in efficiently representing simulation data using lower-dimensional embedding, extracting the underlying knowledge, and obtaining rules to avoid or achieve a certain behavioral pattern. Furthermore, there are many interesting directions worth perusing based on this thesis, (1) Achieving generalizability while using simulations of different mesh criteria. (2) Obtaining validation metrics to validate the results. (3) Using different datasets to evaluate and benchmark the approach given in this study. (4) Defining hyperparameter optimization strategies to efficiently optimize the hyperparameters of the machine learning algorithms used in this thesis. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-7779 CY - Ingolstadt ER - TY - THES A1 - Cardoso Broto, Lucas T1 - Application of low cost pulse radar for heart rate detection in vehicle interior N2 - Contactless human monitoring and radar have been a discussion topic in vehicular technology. This technology applied to interior monitoring may open new opportunities for assistance systems that provide information about the passenger’s health condition. This work characterizes the usage of a low-cost single radio-frequency pulse radar as a mean to assess driver’s respiration and heart rate inside a vehicle. Real data acquisition was performed and the accuracy of the radar evaluated against a ground truth (ECG). Two signal processing techniques were applied and in each proposed scenario: Short Time Fourier Transform (STFT) and Empirical Mode Decomposition (EMD), where STFT presented a better curve fitting and higher accuracy. Y1 - 2020 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-7890 CY - Ingolstadt ER - TY - THES A1 - Ladva, Ronak Madhavji T1 - The decision, planning, and implementation of agile practices within Stage-Gate based PEP Framework for the development of E-dive System N2 - The global market is demanding quick and frequent adaptation to changing customer needs. In order to develop any new system, each organization must define strategies to suit ever-evolving market requirements. In the automotive world, electronics system development projects are also subjected to changing OEM’s standards and requirements. These development projects have become more difficult to plan and execute with traditional project management techniques. There has been a lot of research and modifications to the current project management techniques to make them more adaptable to the changes during the development period. For switching into the new Project management approaches, project team-mindsets must be changed. The training and introduction to such approaches require lots of effort and investments from the top management. Such challenges can be addressed if the new approach has lesser gaps in methodologies than the running system. However, such cases are rare as different project management techniques have unique definitions and solution approaches towards the target. It is always beneficial for any project team to relate and map artifacts from the new system with the current one. This work also addresses such integration of two different project management methodologies. The traditional Stage-Gate method of project management needs proper planning in a single flow approach. On the other hand, most agile project management deals with the iterative approach towards any problem. This work deals with identifying activities from the Stage-Gate-based PEP system, relating them to the Agile terminologies, and planning the structure of the project. The results will determine how mapping with Agile management is done and how the team roles and responsibilities are affected. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8225 CY - Ingolstadt ER - TY - THES A1 - Pfaller, Raphael T1 - Identifikation von Steuergerätplagiaten im Automotivebereich und die Entwicklung eines prototypischen Prüfgeräts N2 - Plagiatskriminalität ist in vielen verschiedenen Industriezweigen anzutreffen. Durch sie erleiden Unternehmen und Käufer teilweise immensen finanziellen Schaden. Auch die Automobilindustrie bleibt von Fälschungen nicht verschont. Diese erstrecken sich von Scheinwerfern, Bremsscheiben und Stoßfängern, über Steuergeräte bis hin zu darin verbauten, einzelnen elektronischen Bauteilen und Controllern. Dabei beschränkt sich die Auswirkung von solchen Plagiaten gerade im Bereich der Steuergeräte nicht nur auf finanzielle Aspekte. Auch die funktionale Sicherheit des Gesamtfahrzeugs kann durch einen nachträglichen Einbau einer Steuergerätefälschung immens beeinträchtigt werden, wodurch sowohl der Fahrer des Fahrzeugs als auch andere Verkehrsteilnehmer in Gefahr geraten können. Um dies zu verhindern, ist es aus Sicht eines Automobilherstellers unabdingbar Anstrengungen gegen diese Art von Kriminalität zu unternehmen, um vor allem auch die eigene Reputation zu wahren. Damit jedoch Maßnahmen gegen Plagiate und deren Hersteller eingeleitet werden können, müssen gefälschte Steuergeräte zunächst identifiziert werden. Diese Arbeit beschäftigt sich mit einer dafür geeigneten Methodik und legt Möglichkeiten offen, mit denen eine Charakterisierung eines Steuergeräts ohne Eingriff in das Gehäuse auf einem Prüfstand erfolgen kann. Hierbei wird ein Fingerabdruck generiert, welcher die Vielzahl an Eigenschaften eines Steuergeräts auf eine Untermenge abbildet und somit die Ermittlung dieser Eigenschaften, sowie deren Vergleich mit anderen, mutmaßlich gefälschten Steuergeräten ermöglicht. Darüber hinaus wird eine Realisierungsmöglichkeit in Form eines kostengünstigen prototypischen Prüfgeräts dargelegt. Dieses übernimmt die Akquisition und Zusammenfassung der einzelnen Charakteristika auf Basis eines beliebig konfigurierbaren Testablaufs. Abschließend werden sowohl die Methoden als auch der Prototyp in Hinblick auf die Differenzierung von Steuergeräten evaluiert. Y1 - 2020 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8432 CY - Ingolstadt ER - TY - THES A1 - Schin, Alexander T1 - Mobile Messdatenerfassung mit Telemetrie und Anzeige von Umweltdaten Y1 - 2020 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8515 CY - Ingolstadt ER - TY - THES A1 - Schwab, Michael T1 - Investigation of drone strike to jet engines BT - preliminary experimental tests, test rig design and numerical analysis N2 - The popularity of unmanned aircraft vehicles increases continuously. The aviation industry focuses this new threat due to elevated probability of collisions with these vehicles in the last few years. This master thesis reports an ongoing, but not finalized yet, research project at the Technische Hochschule Ingolstadt considering collisions between such systems and jet engines. These impacts are considered to be more critical than the exhaustively investigated bird strikes. Relevant statistics and the current state of the art is expounded. By means of a building block approach, a quadcopter is analyzed via quasi-static material tests, drop-tower tests and high-velocity-impact tests. The development of a new test bench for experimental high-velocity-impact tests on fan-blades is described. Appropriate finite element models and impact-simulations are established. Preliminary experimental results show high stiffnesses and also reveal the risk of spark, smoke and fire development of specific drone components. First basic numerical high-velocity-impact simulations with an aluminum impactor on fan-blades display critical failures of the fan assembly. Y1 - 2020 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8540 CY - Ingolstadt ER - TY - THES A1 - Schwan, Hannes T1 - Entwicklung und Verifikation einer Betriebsstrategie für ein hocheffizientes Push-Pull ZCS Class E² induktives Energieübertragungssystem für automobile Anwendungen N2 - In dieser Arbeit wird unter der Berücksichtigung des Einflusses der relativen Position der Übertragungsspulen eines Push-Pull ZCS Class E2 induktiven Energieübertragungssystems für die automobile Anwendung eine Betriebsstrategie entwickelt und experimentell untersucht, ob diese optimales Verhalten unabhängig des Betriebspunktes gewährleisten kann. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8550 CY - Ingolstadt ER - TY - THES A1 - Tabata, Alan Naoto T1 - Object detection and monocular depth sstimation with a custom synthetic automotive dataset N2 - In the automotive industry, the concept of autonomous vehicles is becoming closer to reality, with companies disputing to be the pioneers on reaching at least a level 3 on driving automation. However, before implementing autonomous vehicles on a large scale, research and testing should be performed to assess its safety and reliability. Since one of the ways autonomous vehicles sense its surrounding is through cameras, then one approach to promote human safety is by researching computer vision techniques that may help the vehicle to better understand the context it is in. Therefore, on this work algorithms capable of detecting pedestrians and vehicles, and their distance to the camera are evaluated, in a way that future works can apply corrective trajectory procedures in advance. The main contributions of this work are application and validation of such techniques in a context different from those of which have already been extensively tested on the literature. In this dissertation, this is done by creating a custom CARLA-based synthetic dataset and evaluating its knowledge transfer capability with computer vision algorithms to a real-world dataset, Waymo Open. The purpose of a synthetic dataset is the possibility of generating huge amounts of data at will, a requirement for parametrizing state-of-the-art computer vision models based on deep convolutional neural networks. The Faster R-CNN with a ResNet 50 as backbone was evaluated for the bounding box task, and for monocular depth estimation, the monodepth2 model with a U-Net and ResNet 18 as backbone was evaluated. On the object detection part, it was noted that the injection of synthetic data did not aid in model generalization, with 12% performance decrease when compared to training from scratch on the Waymo skip 10 dataset. For monocular depth estimation, however, the best performing models proved to be different combinations of both synthetic and real-world data, with them improving the performance metrics on average 5% on the Waymo dataset. Overall, it is noted the importance of data variety for both algorithms, with the current synthetic dataset iteration being beneficial for monodepth2 but not Faster R-CNN, which suggests that there is still room for improvement. These observations lead to the conclusion that features which impact positively the model for creating a dataset differ according to the algorithm’s purpose, and as such the creation of an all-purpose dataset is probably not ideal. Y1 - 2020 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8625 CY - Ingolstadt ER - TY - THES A1 - Thavapalan, Thanaancheyan T1 - Implementierung eines Algorithmus zur LIDAR-basierten Exploration mit einer mobilen Roboterplattform N2 - In dieser Bachelorarbeit ging es um das Thema Frontier-Exploration im Bereich der mobilen Robotik. Die Frontier-Exploration basiert auf der Erkennung der Grenzen zwischen bekannten und unbekannten Gebieten. Dazu wurde im Rahmen dieser Arbeit ein Programm implementiert, das diese Grenzen herausfiltert und zu sogenannten Frontiers gruppiert. Auf Basis dieser Gruppierung werden Koordinaten und Orientierungen für alle gefundenen Frontiers berechnet. Anschließend kann eine mobile Roboterplattform diese "Frontiers" anfahren und somit eine Umgebung selbstständig erkunden. Das implementierte Programm wurde in einer Simulation sowie an einem mobilen Roboter getestet. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8630 CY - Ingolstadt ER - TY - THES A1 - Vrabel, Rafael T1 - Entwicklung und Evaluation einer Skala zur Messung des Innovationsgrades technologischer Entwicklungen N2 - Die Wahl der richtigen Innovationsprojekte ist wichtig für ein Unternehmen, um am Markt erfolgreich zu sein. Während monetäre und unternehmenspolitische Faktoren in vielen Innovationsmanagementmodellen zu einem Großteil berücksichtigt werden, weisen diese Modelle im Hinblick auf kundenzentrierte Überlegungen Defizite auf. Jedoch ist die Wahrnehmung der Innovation durch den Kunden einer der wichtigsten Aspekte für einen Erfolg. Anhand der Arbeit von Tomczak et al. wird eine Skala erstellt, um diesen Innovationsgrad bei großen Mengen von Innovationen mithilfe von Nutzern belastbar abfragen zu können. Diese Skala wurde in einer Online Studie (n=91) evaluiert. Die Ergebnisse bestätigen "Neuartigkeit" sowie "Sinnhaftigkeit" als zentrale Determinanten für den Innovationsgrad, sowie die Validität der gemessenen Werte der Skala bzgl. des Innovationsgrades. Y1 - 2021 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8687 CY - Ingolstadt ER - TY - THES A1 - Wollschlager, Marinus T1 - Validation of a CNN classifier for RADAR in real and simulation domain, exclusively trained in simulated RSI model N2 - The current developments in driver assistance systems enabled OEMs to offer vehicles, ready for highly automatic driving (Level 3). A key factor for this development is the environmental perception, based on sensor-systems. Currently, LIght Detection And Ranging (LIDAR), Cameras and RAnge Detection And Ranging (RADAR) are the mainly used sensor-systems, to generate a perception of the vehicular environment. Due to different used spectrums, the performance and reliability of a sensor depends on environmental conditions, like darkness, rain or fog. RADAR is known as a robust sensor, working well also in rain or light conditions. A key feature for an object, surrounding the own car, is a classification, independently of a certain sensor-system. It enables the adjustment of the own trajectory to specific situations, defined by the surrounded objects. Nevertheless, it is challenging to classify an object with RADAR. Common sophisticated automotive classification algorithms rely on camera. But a precise classification of objects, detected by RADAR, gained on importance due to the reliable characteristics of RADAR mentioned before. In addition to real world domain, simulation software provides tools for RADAR measurements and deployment. Even physical sensor models, near to reality, are implemented in software, enabling the improvement of signal processing techniques in a reproducible, convenient and fast manner. RADAR-specific effects, like multipath or clutter, are also implemented. The effects cause so-called "Ghost-Targets", pretending fake objects. This thesis will make a contribution to the question how the simulation of RADAR can be used to classify objects in real world. The classification task is taken over by a CNN classifier. Due to the fact that it is a supervised learning method, the classifier gets trained. Current published papers used real but quit static data for the training. This thesis uses data out of IPG Carmaker 8 simulation model. The proposed methods cluster the data with a state of the art cluster algorithm for RADAR and label, based on ground truth, with a novel approach. A multi-class CNN, implemented in Tensorflow, is enabled to differ between a car, bicycle or pedestrian. The evaluation is concentrated on a confusion matrix. Beside simulation data, also real world data is used to evaluate the classifier. Therefore, a scenario in real world is created. The measurement is performed with INRAS RadarLog, specialized for research and raw data analyze. Both domains, simulation and real world, are scaled on a common frame size and amplitude. The comparison should indicate the potential of a classifier to classify objects with a certain accuracy. The appropriate classifier is exclusively trained in simulation domain and gets applied in the real world and simulation domain. Weather phenomenons like rain, fog or extreme temperatures are excluded in the simulation. Y1 - 2020 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-8727 CY - Ingolstadt ER -