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The rapid evolution of electric vehicles (EVs) necessitates advanced electronic control units (ECUs) for enhanced safety, monitoring, and performance. This study introduces an innovative ECU system designed with a modular architecture, incorporating real-time monitoring, cloud connectivity, and crash sensing. The methodology includes cost-effective design strategies, integrating STM32 controllers, CAN bus systems, and widely available sensors for motor RPM and temperature monitoring. Key findings demonstrate that the proposed ECU system improves data reliability, enhances vehicle safety through crash response systems, and enables predictive maintenance via cloud connectivity. This scalable and affordable ECU is adaptable to a broad range of EV models.
Padma Priya, S.R.Santhipkumar, S.Sasipriya, S.Srivisweswara, M.S.
Faced with one of the greatest challenges of humanity – climate change – the European Union has set out a strategy to achieve climate neutrality by 2050 as part of the European Green Deal. Life Cycle Assessment (LCA), which among other aspects identifies climate change effects, is an important tool to assess the environmental characteristic of sustainable technologies or products to fulfill this ambitious target. In this context, research is presented that examines the ecological sustainability impacts of a metallic vs a composite bipolar plate made of innovative graphite-compound based foils for fuel cell applications. A bipolar plate is a central component of the fuel cell stack to ensure efficiency and durability. For this purpose, a LCA is performed for both bipolar plate materials. This assessment follows the methodology of DIN EN ISO 14040/44 and the EU Product Environmental Footprint framework. Focusing on cradle-to-gate system boundary conditions, the research emphasizes the
van Sloun, AndreasSchroeder, BenediktKexel, JannikSchmitz, MaximilianBalazs, AndreasWalters, MariusKoßler, SilasPischinger, StefanJoemann, Michael
Usually, scenarios for testing of advanced driver assistance systems (ADAS) are generated utilizing certain scenario and road specification languages such as ASAM OpenSCENARIO and OpenDRIVE. Directly adopting these low-level languages limits the rate in which new scenarios are generated for virtual testing. Natural language (NL) would allow a much broader group of people and artificial intelligences to generate scenarios, increasing test coverage and safety. Instead of trying a direct translation from NL into OpenX, the existing intermediate domain specific language (DSL) stiEF is used. This not only facilitates testing and debugging but also generation, as its grammar can be used as a constraint for a large language model (LLM), which is then able to translate NL into stiEF. A parser is applied in an agentic way that interacts with the LLM until a syntactically correct file is generated, an optional second agent is then used to do basic semantic verification. Finally, the translation
Vargas Rivero, Jose RobertoBock, FlorianMenken, Stefan
This paper examines the influence of a detailed dynamic model of a Surface Permanent Magnet Synchronous Motor (SPMSM) on the accurate evaluation of kinetic energy recovery during braking in a mild hybrid vehicle. The model, implemented in MATLAB Simulink, is based on the motor’s DQ equivalent circuit, accounting for transient effects, inductance variability, and magnetic saturation. Also, a 2nd Order Thevenin Equivalent model of the battery is used in order to take into account the bus voltage variability. Simulations reveal that the dynamic model predicts significant variations in energy recovery potential, with differences of up to 25% compared to static models under specific braking conditions. These discrepancies are particularly pronounced during high-speed high-torque transitions, where transient electrical behaviors strongly influence energy recovery. The model’s accuracy enhances the reliability of energy simulations, especially in scenarios involving frequent or intense
Lombardi, SimoneFederici, LeonardoTribioli, LauraBella, Gino
Problem definition: Battery-electric commercial vehicles in particular have large battery capacities with several hundred kilowatt hours, some of which do not have enough energy for an entire working day, which is why they need to be recharged if necessary. High charging power with correspondingly high charging currents is required to recharge the electrical energy storage in an acceptable time. Due to the electrical losses, waste heat is generated, which places a thermal load on the charging components. In particular, the CCS charging inlet is subject to high thermal loads and, for safety reasons, must not exceed the maximum temperature of 90°C according to DIN EN IEC 62196-1. Depending on the ambient temperature, the charging inlet in the charging path often represents a thermally limiting component, as the charging current must be reduced before the maximum temperature is reached. Solution: Three general solution approaches are used to investigate how the CCS charging inlet can be
Krings, JochenReuss, Hans-ChristianZiegler, PeterSteinmetz, Paul
The future of the internal combustion engine (ICE) is closely tied to its ability to achieve life cycle emissions comparable to those of pure battery electric vehicles (BEVs). To reach this goal, it is essential not only to utilize carbon-free fuels but also to enhance the hybridization of the powertrain to reduce fuel consumption. Additionally, it is crucial to minimize pollutant emissions to near-zero levels, necessitating the development of highly sophisticated exhaust aftertreatment systems. For Plug-In Hybrid Electric Vehicles (PHEVs), one particular use case is the High-Power Cold Start (HPCS). This scenario occurs when the transition from pure electric drive to ICE-assisted drive happens during a high load request, such as accelerating on a freeway ramp. This use case has been evaluated by CARB and in numerous other studies. However, in this paper, the authors aim to investigate which metallic substrate technology performs best during an HPCS. This condition differs
Montenegro, GianlucaOnorati, AngeloMarinoni, AndreaDella Torre, AugustoPace, LorenzoKonieczny, KatrinLaurell, MatsKlövmark, Henrik
Power hop is a vibration phenomenon that occurs during high accelerations from low speed. In severe cases it can lead to component damage or deformation. Therefore, the affected vehicles must be safeguarded against these vibrations by a safe design of the components and by additional software-based functions. Conventional software-based solutions, such as Traction Control Systems (TCS), often perform delayed interventions and apply harsh torque adjustments that reduce driving comfort. Motivated by these challenges, this paper proposes a novel approach for power hop detection in a high-torque vehicle based on Long Short-Term-Memory Network (LSTM) and real-time measurements. Unlike conventional methods, our LSTM precisely detects the start of power hop, enabling proactive torque adjustments. Due to its impact on vehicle stability, the model must achieve a high level of reliability and robustness. Given the importance of data quality in Machine Learning (ML), we consider data-related
Chehoudi, MoatezMoisidis, IoannisSailer, MarcPeters, Steven
This paper deals with autonomous vehicle trajectory planning for avoidance maneuver. It introduces a trajectory planning approach that allows for static obstacle avoidance maneuvers. Specifically, this study proposes a generalized geometric formulation based on Sigmoid functions in order to generate a smooth path that guides the vehicle on a lateral deviation and returns to the initial lane. In addition, the method considers various geometrical and dynamic constraints to ensure vehicle stability while taking into account a safety area around the obstacle. The algorithm validation is conducted on the professional CarMaker simulator by associating the path generation module with a robust lateral tracking controller. The results demonstrate the effectiveness of the proposed planning method in the field of autonomous driving vehicle control.
Vigne, BenoitGiuliani, Pio MicheleOrjuela, RodolfoBasset, Michel
The automotive industry faces the challenge of developing vehicles that meet current customer needs while being future-proof. Surveys conducted for this study show that customers are concerned about the financial risks of essential components such as energy storage systems, mainly due to aging and performance degradation, which significantly affect vehicle lifespans. Based on vehicle developer surveys, a clear need for action was identified. Given the rapid technological advancements in electrified drive systems, there is a need for innovative approaches that can easily adapt to changing requirements. Therefore, this paper presents a strategy combining foresight-based planning of system upgrades with product architecture design to create adaptable and sustainable vehicles through modularity. First, dynamic subsystem characteristics are identified to establish future energy storage technology requirements. Subsequently, future energy storage system technologies are examined to determine
Fehrenbacher, RüdigerKuebler, MaximilianZeng, YunyingBause, KatharinaAlbers, AlbertNootny, FabioKolbe, LuciaJung, Luca
It is becoming increasingly clear that research into alternative fuels, including drop-in fuels, is essential for the continued survival of the internal combustion engine. In this study, the authors have evaluated olefinic and oxygenated fuels as drop-in fuels using a single-cylinder engine and considering fuel characteristic parameters. The authors have assessed thermal efficiency by adding EGR or excess air from zero to the maximum value that allows stable combustion. Next, we attempted to predict fuel efficiency for four types of passenger cars (Japanese small K-car N/A, K-car T/C, Series HV, and Power-split HV) by changing the fuels. We created a model to estimate fuel efficiency during WLTC driving. The results indicated that fuel economy could potentially be improved by adding an olefin fuel that burns stably even with a large amount of EGR or air and an oxygen fuel whose octane number increases. It was observed that the fuel economy improvement rate was particularly notable for
Moriyoshi, YasuoXu, FuguoWang, ZhiyuanTanaka, KotaroKuboyama, Tatsuya
In electric vehicles, the control of driveline oscillations and tire traction is critical for guaranteeing driver comfort and safety. Yet, achieving sufficient driveline control performance remains challenging in the presence of rapidly varying road conditions. Two promising avenues for further improving driveline control are adaptive model predictive control (MPC) and model-based reinforcement learning (RL). We derive such controllers from the same non-linear vehicle model and validate them through pre-defined test scenarios. The MPC approach employs input and output trajectory tracking with soft constraints to ensure feasible control actions even in the presence of constraint violations and is further supported by a Kalman filter for robust state estimation and prediction. In contrast, the RL controller leverages the model-based DreamerV3 algorithm to learn control policies autonomously, adapting to different road conditions without relying on external information. The results
Uhl, Ramón TaminoSchüle, IsabelLudmann, LaurinGeist, A. René
The decoupling of software from hardware in automotive systems, driven by the rising share of software in modern vehicles, has introduced a paradigm shift, enabling various software configurations on identical hardware platforms. Consequently, ensuring the correct functionality and reliability of the electric and electronic hardware components, testing and commissioning processes in the vehicle production have grown in importance and complexity. However, the efficiency of these processes relies on diverse datasets, for example parameterization data that allows tailored testing based on the vehicle’s equipment configuration. Therefore, the availability and accuracy of this data need to be guaranteed. Data for testing and commissioning, influenced by the digitization of production processes and their planning, is not only facing the challenges of greater software volumes and faster update cycles, but also those arising from legacy processes or the integration of various IT systems into
El Asad, AimanKöhler, KatjaHahn, MichaelReuss, Hans-Christian
Wind Tunnels are complex and cost-intensive test facilities. Thus, increasing the test efficiency is an important aspect. At the same time, active aerodynamic elements gain importance for the efficiency of modern cars. For homologation, such active aero-components pose an extra level of test complexity as their control strategies, the relevant drive cycles and their aerodynamics in different positions must be considered for homologation-relevant data. Often, active components have to be manually adjusted between test runs, which is a time-consuming process because the vehicle is not integrated into the test automation. Even if so, designing a test sequence stepping through the individual settings for each component of a vehicle is a tedious task in the test session. Thus, a sophisticated integration of the wind tunnel control system with a test management system, supporting the full homologation process is one aspect of a solution. The other is the integration of the vehicle’s active
Jacob, Jan D.
Vibration control is most important in automotive applications, and generally, rubbers are used to dampen these vibrations due to their inherent nature and low-cost manufacturing methods. Now, to select a rubber material, Shore hardness is considered in engineering applications, but to additionally control the behaviour, we need to understand its static and dynamic stiffness. These values help to determine the vibration isolation obtained by these rubbers. In this paper, we will discuss methods to calculate the static and dynamic stiffness of rubber grommets using experimental methods and FEA modelling. As elastomers have non-linear material properties, various material modelling techniques in FEA are used to capture multiple phenomena like creep, fatigue, and dynamic conditions. Rubber compounding is used in order to improve the physical and chemical properties, which in turn would give desirable linear characteristics. Certain guidelines and thumb rules are used in the rubber
Khamkar, Prasad SubhashGaikwad, Vikrant Chandrakant
PEM fuel cell technology plays a vital role in realizing an emission-free mobility and, depending on the considered use case, offers significant advantages over battery electric solutions as well as hydrogen combustion engines. When high performance over a longer period of time as well as short refueling times are key requirements, fuel cell powertrains show their core strengths. However, the adaption of fuel cells in the mobility sector strongly depends on their efficiency which directly relates to the vehicle’s fuel consumption, range and ultimately cost to operate. Therefore, the influence on efficiency and power of different purge strategies used to operate PEM fuel cells is experimentally investigated and compared. A concentration-dependent purge strategy is developed and examined in reference to a charge-dependent strategy. The measurements are carried out on a fuel cell system test bench which corresponds to a fully functional fuel cell system including all commonly used
Hauser, TobiasAllmendinger, Frank
The brake system is a critical safety component in motor vehicles. Advances in the electrification of the powertrain and the rise of autonomous driving technologies are significantly impacting the brake system, which allows innovative approaches and necessitating the development of new brake concepts and new deceleration strategies. A major technological advance is the decoupling of the driver from the brake system through Brake-by-wire technology. A crucial attribute of Brake-by-wire systems is the attainment of a concept-independent deceleration behavior. To establish a consistent and brand-specific deceleration behavior in the early development phase, objective metrics and perceptual thresholds are required to describe the desired subjective braking behavior. Moreover, objective metrics are indispensable for the virtual phase of the vehicle development process. This article focuses on deceleration from a straight-ahead drive. To identify objective metrics and perceptual thresholds
Biller, RalphUdovicic, MatejKetzmerick, ErikKirch, SebastianMayr, StefanProkop, GüntherWagner, Andreas
Transitioning to zero-carbon fuels is pivotal for expediting the reduction of carbon emissions. Hydrogen demonstrates significant adaptability and emerges as a principal zero-carbon alternative fuel for fossil fuel internal combustion engine (ICE) platforms. Implementing hydrogen in both spark ignition (SI) and compression ignition (CI) engines has proven to be both economically viable and timely. In this study, a conventional diesel engine was operated with pure hydrogen with minimal modification to engine hardware. It features a proactive, automated shutdown system to mitigate intake backfire risks associated with hydrogen port fuel injection (PFI) systems. A comprehensive engine characterisation was conducted using a lambda sweep test, measuring values from 1.5 to 4.5 with an integrated in-cylinder pressure transducer for high-resolution data. The study used an advanced Bandpass, Rectify, Integrate, Compare (BRIC) knock detection method for engine health monitoring and assessed
Mohamed, MohamedZaman, ZayneLu, EnshenFeng, YizhuoWang, XinyanZhao, Hua
While semi-autonomous driving (SAE level 3 & 4) is already partially a reality, the driver still needs to take over driving upon notice. Hence, the cockpit cannot be designed freely to accommodate spaces for non-driving related activities. In the following use case, a mobile workplace is created by integrating a translucent acrylic glass pane into the cockpit and introducing joystick steering of the car. By using the technology Virtual Desktop 1, which is a software layer, any desktop application can be represented freely transformable on arbitrary physical and virtual surfaces. Thus, a complete Windows environment can be distributed across all curved and flat surfaces of an interior. The concept is further enhanced by a voice-driven generative AI which helps to summarize documents. A physical and a virtual demonstrator are created to experience and assess the mobile workspace, the well-being of the driver, external influences, and psychological aspects. The physical demonstrator is a
Beutenmüller, FrankReining, NineRosenstiel, RetoSchmidt, MaximilianLayer, SelinaBues, MatthiasMendonca, Daisy
Hydrogen produced from renewable sources offers the opportunity to reduce future emissions and enable CO2-neutral mobility by both adapting existing internal combustion engines (ICE) and developing new combustion engine systems. One challenge of hydrogen direct injection (DI) ICE is to optimize the mixture formation to ensure low engine out emissions as well as high efficiencies. In the study presented in this paper, a conventional piezo hollow-cone gasoline injector, commonly used in passenger car series, was adapted for high-pressure hydrogen direct injection applications. Therefore, optical measurements within a low pressure chamber (LPC) were conducted using a high-speed Schlieren imaging measurement technique to visualize the injection behavior and jet pattern at various injection conditions. The visualization of density gradients during the injection process showed a slightly decreased relative gaseous penetration length (GPL) of 4% for hydrogen in comparison to helium while the
Fleischmann, MaximilianMirsch, NiklasGhanoum, MohamadMorcinkowski, BastianAdomeit, PhilippPischinger, Stefan
This study analyses the effect of external damping of roller bearings on the acoustic behaviour of gearboxes in electric powertrains. The growing use of electric vehicles has increased the importance of reducing gearbox noise, as the lack of noise masking from internal combustion engines and the higher operating speeds of electric motors exacerbate the acoustic challenges. Gearbox noise, which is primarily caused by tooth mesh excitation and its transmission through shafts and bearings, requires strategies to minimise its impact on vehicle comfort and performance. External damping is achieved through the integration of specific elements at the circumference of the outer bearing ring. These elements are utilised to modify the vibration transfer behaviour of the bearing assembly. This, in turn, can lead to a reduction in both structure-borne and airborne noise emissions at the gearbox housing. A test design was created to quantify the effects of different damping configurations. This
von Schulz, KaiLinde, TilmannJäger, Steffen
This paper presents a coupled electromagnetic and thermal simulation of Permanently Excited Synchronous Machines (PMSM) in the context of virtual prototyping in a real-time Hardware-in-the-Loop (HiL) environment. Particularly in real-time simulations, thermal influences are often neglected due to the increased complexity of a coupled simulation. This results in inaccurate simulations and incomplete design optimizations. The objective of this contribution is to enable a precise and realistic real-time simulation that represents the electromagnetic as well as the thermal behavior. The electromagnetic simulation is executed used a Field-Programmable Gate Array (FPGA) and parameterized by Finite Element Analysis (FEA) results. The thermal model is based on a Lumped-Parameter-Thermal-Network (LPTN), which is based on physical laws, geometry parameters and material specifications. The simulation results are validated with testbench measurements to ensure the accuracy of the overall model. By
Jonczyk, FabianKara, OnurBergheim, YannickLee, Sung-YongStrop, MalteProchotta, FabianAndert, Jakob
The larger size and expanded blind spots of heavy-duty trucks in comparison to passenger cars, create unique challenges for truck drivers navigating narrow roads, such as in urban scenarios. For this reason, the detection of free space around the vehicle is of critical importance, as it has the potential to save lives and reduce operating costs due to less maintenance and downtime. Despite the existence of numerous approaches to free space detection in the literature, few of these have been applied to the trucking sector, disregarding important aspects for these kinds of vehicles such as the altitude at which obstacles are located. This paper aims to present the initial results of our research, a “Not Free Space Warner”, a driving assistance function intended for implementation in series trucks. A methodology is followed to define the characteristics that the perception component of this function shall fulfill. To this end, an analysis of the most critical accidents and common driving
Martinez, CristianPeters, Steven
Non-exhaust particle emissions, particularly those generated by brake wear, are a significant source of fine particulate matter in urban environments. These emissions contribute to air pollution and pose serious health risks, particularly in densely populated areas. While vehicle exhaust emissions have been extensively studied and regulated, the contribution of non-exhaust sources, including brake wear, remains a critical factor in air quality management. This paper presents a novel methodology for fast-running, time-resolved simulation of non-exhaust particle emissions, specifically those from brake wear abrasion. A 3D CFD model computes the turbulent flow field around the disc brake. The resulting information on the convective air cooling is applied as boundary conditions on a 3D thermal model. This thermal simulation setup is compared and verified with experimental data from literature. The 3D numerical models produce data and boundary conditions for an efficient 1D numerical
Herkenrath, FerrisLückerath, MoritzGünther, MarcoPischinger, Stefan
The road network is a critical component of modern urban mobility systems, with signalized traffic intersections playing a pivotal role. Traditionally, traffic light phase timings and durations at intersections are designed by transportation engineers using historical traffic data. Some modern intersections employ trigger-based mechanisms to improve traffic flow; however, these systems often lack global awareness of traffic conditions across multiple intersections within a network. With the increasing availability of traffic data and advancements in machine learning, traffic light systems can be enhanced by modeling them as agents operating in an environment. This paper proposes a Reinforcement Learning (RL) based approach for multi-agent traffic light systems within a simulation environment. The simulation is calibrated using real-world traffic data, enabling RL agents to learn effective control strategies based on realistic scenarios. A key advantage of using a calibrated simulation
Kalra, VikhyatTulpule, PunitGiuliani, Pio