Browse Topic: Tests and Testing

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Agentic generation of OpenX files from natural language descriptions2025-01-0299To be published on 07/02/2025
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 Roberto, Bock, Florian, Menken, Stefan
Technical Paper
Improving Gearbox Acoustics Through Elastomer-Based Bearing Damping2025-01-0323To be published on 07/02/2025
This study analyses the effect of external damping of roller bearings on the acoustic behaviour of gearboxes in electric powertrains. The increasing adoption of electric vehicles has increased the importance of mitigating gearbox noise, as the lack of masking noise 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 introduced via adapters integrated into the outer bearing ring, which are used to modify the vibrational behaviour of the bearing assembly and reduce both structure-borne and airborne noise emissions. A systematic approach using Design of Experiments (DoE) methodology is used to quantify the effects of this damping. This approach allows the analysis of critical parameters including material
von Schulz, Kai, Linde, Tilmann, Jäger, Steffen
Technical Paper
Efficient Automation of Homologation Tests for Active Aerodynamic Components2025-01-0273To be published on 07/02/2025
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 become increasingly important 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, these active components are time-consuming manually adjusted during between test runs as the vehicle is not incorporated in the test automation architecture. Even if so, designing a test sequence stepping through the individual settings for each component of a certain vehicle is a tedious task during the test session. Thus, a sophisticated integration of the wind tunnel automation system with a test management system, which supports the full homologation process is one aspect of a solution. The other is the integration
Jacob, Jan D.
Technical Paper
Strategies for Improving Data Management in Automotive Testing and Commissioning Processes2025-01-0277To be published on 07/02/2025
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 these 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, Aiman, Köhler, Katja, Hahn, Michael, Reuss, Hans-Christian
Technical Paper
Experimental Evaluation of Purge Strategies in the Recirculation Path of a PEM Fuel Cell System2025-01-0316To be published on 07/02/2025
PEM fuel cell technology plays a vital role in realizing an emission-free mobility and, depend-ing 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 refuelling 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-dependant purge strategy is developed and examined in reference to a charge-dependant strategy. The concentration-dependent purge strategy manages the purge process based on the measured hydrogen concentration in the anode recirculation path. The
Hauser, Tobias, Allmendinger, Frank
Technical Paper
Longitudinal Dynamic Metrics for Describing and Developing the Deceleration Behavior of Vehicles in the Concept Phase2025-01-0264To be published on 07/02/2025
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 profoundly influencing the brake system, driving innovative approaches to brake concepts and necessitating the development of new deceleration strategies. A significant technological advancement is the decoupling of the driver from the brake system through Brake-by-Wire technology. A crucial attribute is the attainment of a consistent and concept-independent deceleration behavior and pedal feel. To establish a consistent and OEM-specific deceleration behavior and pedal feel in the early development phase, objective criteria and perceptual thresholds are required, describing the desired subjective braking behavior. Moreover, objective criteria are indispensable for the virtual phase of the vehicle development process. In this article the focus is in deceleration from a straight-ahead drive. To identify objective criteria
Biller, Ralph, Udovicic, Matej, Ketzmerick, Erik, Kirch, Sebastian, Mayr, Stefan, Prokop, Günther, Wagner, Andreas
Technical Paper
Exploring the Correlation Between Physiological States and Driving Behavior on Highways with Integrated ECG Measurements2025-01-0292To be published on 07/02/2025
Human driver errors, such as distracted driving, inattention, and aggressive driving, are the leading causes of road accidents. Understanding the underlying factors that contribute to these behaviors is critical for improving road safety. Previous studies have shown that physiological states, like raised heart rates due to stress and anxiety, can influence driving behavior, leading to erratic driving behaviors and an increased risk of accidents. In this study, we conducted on-road tests using a measurement system based on the Driver-Driven vehicle-Driving environment (3D) method. We collected physiological signals, specially electrocardiogram (ECG) data, from human drivers to examine the relationship between physiological states and driving behaviors. The aim was to determine whether ECG could serve as an indicator of potential risky driving behaviors, such as sudden acceleration and frequent steering adjustments. This information could enable automated driving systems (AD) to
Ji, Dejie, Flormann, Maximilian, Bollmann, Julian, Henze, Roman, Deserno, Thomas M.
Technical Paper
Application of Sustainable Aviation Fuels in Compression-Ignition Aviation Engines: In-Flight Investigations2025-01-0317To be published on 07/02/2025
To achieve a significant reduction in net CO₂ emissions in the aviation sector, sustainable aviation fuels (SAFs) are considered a key factor. Current research efforts are therefore focused on SAFs, which exhibit properties that differ from conventional kerosene, particularly in aspects critical to compression-ignition (CI) engines, such as cetane number, evaporation behavior or lubricity. These differences necessitate dedicated investigations to assess their suitability and performance in such engines. However, real operating conditions — such as intake air- and exhaust- pressure levels during flight — cannot be fully replicated on standard engine test benches. For this reason, real flight experiments were conducted to address these limitations. Notably, this work marks the first instance of in-flight testing of SAFs in CI aviation engines, constituting a significant milestone in this research area. In the course of these investigations, ASTM D7566 Annex A2-compliant HEFA
Kleissner, Florian, Reitmayr, Christian, Hofmann, Peter
Technical Paper
A Pich Shift Synthesis Algorithm for Electric Vehicle Sound Based on Quadratic Interpolation and Continuous Sample Indexing2025-01-0254To be published on 06/16/2025
The electric vehicle driveline generates less vibration and noise compared to a conventional internal combustion engine vehicle, making it hard-er for the driver to perceive the vehicle’s operating status through driveline sounds, thereby diminishing driving engagement and experience. To compensate for the absence of engine sound in EV drivelines, Active Sound Design (ASD) technology has become a crucial method for drivetrain sound enhancement, with sound synthesis algorithms playing a key role in this process. Although pitch-shifting algorithms based on frequency variation principles can synthesize engine sounds, they suffer from spectral leakage and stuttering caused by sound splicing. To ad-dress these issues, a pitch-shifting synthesis algorithm (QCPS) is proposed in this paper, which combines a quadratic interpolation method with a continuous audio sample indexing strategy. First, the frequency variation coefficient of the sound is calculated. Based on this coefficient
Liu, Dezhu, Xie, Liping, Liu, Zhien, Lu, Chihua
Technical Paper
Ammonia-diesel Engines Segmented Modeling approach and Simplified Combustion model Research2025-01-0232To be published on 06/16/2025
Ammonia-diesel dual-fuel engines can effectively reduce greenhouse gas (GHG) emissions. Aiming at the real-time control requirements of ammonia/diesel dual-fuel engines, this study proposes a segmented real-time modeling method and a heat release rate model simplification strategy by linearized heat release rate curves. First, the engine working cycle is divided into three parts: intake and exhaust stage, compression and expansion stage, and combustion process. Different simulation steps and modeling strategies are designed to optimize computational efficiency while maintaining the necessary level of accuracy at each stage. Secondly, based on the calibrated heat release rate (HRR) curves, feature points are extracted to construct a simplified linear heat release model. In the absence of calibration data, the characteristic points of the HRR curves are obtained through interpolation. Compared with the commonly used combustion model, the Wiebe model, the proposed simplified model can
Li, Guangyuan, Chen, Run, Wang, Xinran, Li, Tie, Zheng, Kexiong, Liu, Shaoling, Liu, Yanchao, Lyu, Xiaodong
Technical Paper
New system for the measurement of sound-insertion loss on small samples: a comparison with ASTM-E2611 and ASTM E90 test procedures2025-01-0116To be published on 05/05/2025
This article follows a companion article presented at the SAE NVC 2021, in which a new system for the measurement on small samples of the normal-incidence Insertion Loss (IL) of multilayers used for the manufacturing of automotive sound package parts was first introduced. In addition to simplifying the evaluation of the sound-insulation of multi-layers used to produce sound-package components, the system aims to overcome the limitations of the test procedure based on the ASTM E2611 standard. In this article, the latter point is demonstrated by comparing the insertion loss results obtained with the new system with those obtained with the test procedure based on the ASTM E2611 standard on a few multilayers commonly used for the manufacturing of automotive sound package parts. Results indicate that the results obtained by means of the newly developed system are more meaningful, practically usable and less prone to edge-effects, compared to those obtained according to the ASTM E2611 test
Ruggeri, Giulio, Bertolini, Claudio, Horak, Jan
Technical Paper
Identification and Evaluation of Passthroughs That Affect the Acoustic Performance of a Dash System2025-01-0121To be published on 05/05/2025
This paper discusses a systematic process that was developed to evaluate the acoustic performance of a production electric vehicle dash system. The production dash panel was tested under different configurations to understand the importance of passthroughs in the acoustics of the dash system. Results show that often the performance of the passthroughs strongly affects the overall performance of the dash system and this may become the limiting factor to increase the system STL. The dash with passthroughs was then extensively tested to understand the acoustic strength of different passthroughs and to understand how these passthroughs affect the overall performance of the dash system. Subsequently a test procedure based on flat panel tests was developed so the OEM can develop target values and the suppliers can provide test results of their passthroughs that are meaningful and useful to the OEM to help build an acoustically competitive vehicle.
Saha, Pranab, Baack, Gregory, Geissler, Christian, Kaluvakota, Srikanth, Pilz, Fernando
Technical Paper
NVH improvement of the BEV transmission by altering bearing mounting arrangement.2025-01-0104To be published on 05/05/2025
As per metaphor, “The squeaky wheel gets the grease” the transmission of battery electric vehicle (BEVs) gets topmost attention in terms of NVH improvement. While the engine is getting replaced with an almost silent electric motor, the transmission noise appears persistent and demands more silent transmission. This has raised demand for improvement in design as well as manufacturing quality. Various innovations are being done to drive an improvement in the NVH. Following paper will discuss the improvement in NVH achieved through a design innovation in the way bearings are installed and demonstrated a significant amount of improvement. We have used SMT MASTA used as a simulation tool to predict the expected results and a Transmission Dyno test bench in an anechoic chamber to test the NVH performance on physical sample. The innovation was done on a small single speed two stage reduction gearbox coupled with a 100 NM, 14000 RPM battery electric motor. Though the bearings have
Pingale, Abhijeet, Soni, Jaldeep
Technical Paper
Evaluation of invariant structural and acoustic loads estimation methods to be used in vehicle platform development independent to the boundary conditions of load generation.2025-01-0053To be published on 05/05/2025
Platform based vehicle development is standardized at Deere. The challenges of frontloading the integration effects of individual components within different platforms using predictive methods is key to shorten the development cycle. Components are generally characterized on test benches and can not directly be used to evaluate system performance. Invariant characterization is needed which is possible through techniques such as blocked loads estimation. To evaluate the applicability of such methods, the test stand based, and vehicle in-situ operational loads needs to be compared. The confident use of these methods for structural and acoustic loads enables the use of combination of test and simulation models of common components and system modules in a variety of products, enhancing early NVH response predictions. In this work, we compare a powertrain characterization in a vehicle and a test stand to assess the invariance of the operating mount structural loads as well as operating
Vesikar, Prasad Balkrishna, Edgington, Jason, Drabison II, John
Technical Paper
Characterize the Sound Field Generated from a Vehicle Horn by Pellicular Analysis2025-01-0058To be published on 05/05/2025
To predict the sound field produced by a vehicle horn requires a good source representation of it in the full vehicle model. This paper investigates the characterization of a physical vehicle horn by an inverse method called pellicular analysis. To implement this method, firstly an acoustic testing is performed to measure the sound pressure radiated from the horn at a certain number of microphone locations in a free field environment. Based on the geometry of a virtual horn, the locations of each microphone and measured sound pressure data, pellicular analysis is adopted to recover a set of vibration pattern of the virtual horn. The virtual horn and the recovered vibration information are then incorporated in a full vehicle numerical model to simulate its exterior sound field. The validity of this approach is confirmed by comparing the prediction for a horn in a production vehicle to the corresponding physical test which is required to meet the Brazilian regulation CONTRAN 764/2018.
Yang, Wenlong, Melo, Andre
Technical Paper
Experimental Investigation on Genetic Algorithm optimized Proportional Integral Derivative Based Active Suspension System2025-01-0014To be published on 05/05/2025
In this work, Genetic Algorithm (GA) optimized Proportional Integral Derivative (PID) controller is employed. The PID gain values are optimally tuned based on the objective function formulated using the Integral Time Absolute Error (ITAE) criteria of various suspension measures like vehicle body displacement, suspension and tire deflections. The proposed GAPID controller is experimentally validated through the 3-DOF quarter-car test rig model. The fabricated model with passive suspension system (PASS) and active suspension system (ACSS) provided with an electrical actuator as base excitation is pictured. The schematic representation of the fabricated test set-up with and without ACSS is also illustrated. Further, simulation and experimental response of the fabricated model with and without ACSS are compared. It is identified that the proposed GAPID controller attenuates the sprung mass acceleration by about 41.64 % and 29.13 % compared with PASS for the theoretical as well as
A, Arivazhagan, Kandavel, Arunachalam
Technical Paper
Active Control of Engine Order Noise for Heavy-duty Trucks: Using the Genetic Algorithm for the Optimization of Error Microphone Arrangement2025-01-0013To be published on 05/05/2025
The arrangement of error microphones for a vehicle active noise control (ANC) system is no trivial work, especially for heavy-duty trucks due to the dilemma resulted from the large volume of the cab and the limited number of microphones accepted by most manufacturers in the auto industry. Most ANC developers resort to trial and error, which is not only a heavy workload given the amount of interested working conditions to be test, but also does not guarantee to yield the optimum noise cancellation performance. In this paper, the authors proposed an error microphone selection methodology using a genetic-algorithm (GA) -based mechanism. The target vehicle was a heavy-duty truck with a six-piston diesel engine, and two scenarios were particularly interested, i.e. driver & copilot and driver & one passenger sleeping on the berth. We first arranged eight microphones at different locations in the cab, five on the headrests, two on the B pillars and one at the head position of the sleeping
Wang, Jian, Ling, Zihong, Zhang, Zhe, Cai, DeHua, lv, Xiao, Zhang, Ming, Gao, GuoRan
Technical Paper
Study on the Aspiration Properties of Glassrun Seal System under Time-Varying Pressure Difference2025-01-0030To be published on 05/05/2025
When a vehicle is driven at high speed, there exists intricate flow pattern and vortex shedding at the side window area with intense pressure fluctuation. A significant dynamic pressure difference between the vehicle's exterior and interior can render the side window sealing system vulnerable to aspiration. This susceptibility can lead to the generation of leakage noise, adversely affecting acoustic comfort in the vehicle's cabin. This paper delves into the aspiration properties of glassrun seal system under time-varying pressure difference. A nonlinear finite element model of the glassrun seal was established to simulate the quasi-static deformation of the sealing strip during installation process, which aims to obtain the deformed geometric shape and residual stress after this process. Then, the exterior flow field of the glassrun sealing area of a simplified vehicle model was calculated with CFD simulation to obtain the hydrodynamic pressure excitation acting on the outer surface of
Li, Hanqi, He, Yinzhi, Zhang, Lijun, Zhang, Yongfeng, Yu, Wuzhou, Jiang, Zaixiu, Blumrich, Reinhard, Wiedemann, Jochen
Technical Paper
Leveraging user feedback to optimize the tuning of EVSE models2025-01-0020To be published on 05/05/2025
The implementation of active sound design models in vehicles requires precise tuning of synthetic sounds to harmonize with existing interior noise, driving conditions, and driver preferences. This tuning process is often time-consuming and intricate, especially facing various driving styles and preferences of target customers. Incorporating user feedback into the tuning process of Electric Vehicle Sound Enhancement (EVSE) offers a solution. A user-focused empirical test drive approach can be assessed, providing a comprehensive understanding of the EVSE characteristics and highlighting areas for improvement. Although effective, the process includes many manual tasks, such as transcribing driver comments, classifying feedback, and identifying clusters. By integrating driving simulator technology to the test drive assessment method and employing machine learning algorithms for evaluation, the EVSE workflow can be more seamlessly integrated. But do the simulated test drive results
Hank, Stefan, Kamp, Fabian, Gomes Lobato, Thiago Henrique
Technical Paper
Correlated Beamforming Based on Deconvolution Methods for Identified Vehicle Exterior Wind Noise Sources and Interior Noise2025-01-0025To be published on 05/05/2025
Sound source identification based on beamforming is widely used today as a spatial sound field visualization technology in wind tunnel experiments for vehicle development. However, the conventional beamforming technique has its inherent limitations. To improve the performance, three deconvolution methods CLEAN, CLEAN-SC and DAMAS were investigated. These algorithms were applied for the wind noise sources identification on a production car. After analysis of vehicle exterior wind noise sources distribution, to study the energetic contribution of identified exterior noise sources to interior noise, correlation analysis between them were conducted. The results show that, the algorithm CLEAN-SC based on spatial source coherence shows the outstanding capability to remove the sidelobes for the uncorrelated wind noise sources, while CLEAN and DAMAS which based on point spread function have definite limitations. In the application aspect, the main noise source outside vehicle is from the
He, Yinzhi, Shen, Henghao, Wu, Yu, Zhang, Lijun, Yang, Zhigang, Blumrich, Reinhard, Wiedemann, Jochen
Technical Paper
HV-Battery Impact on Car Body Acoustics and Damping Package Case Study of the Electric Vehicle2025-01-0041To be published on 05/05/2025
Damping treatments are playing an important role in the definition of efficient acoustic packages for passenger cars with all types of propulsion systems. Many parts of the damping layout are identical for all vehicles including treatments of wheelhouses, spare wheel area, roof panels etc. However, there are some characteristics in car body acoustics associated with the presence of the battery in electric vehicles, which need to be considered in the definition of the efficient damping package. The presented paper investigates the impact of the HV-battery on interior noise related characteristics of the car body using laser scanning vibrometry and 3D acoustic intensity test methods. Findings are used in the subsequent optimization of the initial damping package resulting in various package proposals with different lightweight and acoustic requirements. New damping package variants are evaluated in the lab by laser vibrometry tests and the impact on interior noise is addressed by road
Unruh, Oliver, Gielok, Martin
Technical Paper
The DANA EV NVH Laboratory2025-01-0007To be published on 05/05/2025
A cutting-edge EV powertrain NVH laboratory has been established at DANA Incorporation’s world headquarters in Maumee, enhancing their capabilities in EV powertrain NVH development. This state-of-the-art and industry lead laboratory is designed to meet various NVH requirements for EV powertrain development and sign-off processes. This laboratory supports the use of a live motor for input and is equipped with an input module that allows for detailed examination of NVH characteristics of new powertrain configurations before prototype motors are available, significantly reducing development time for new drivetrain systems. Key features of the laboratory include a hemi-anechoic chamber, two AC asynchronous load motors, an acoustically isolated high-speed input motor, and two battery emulators that cover both low and high voltage requirements. The NVH laboratory enables engineers to assess system performance and correlate it with digital twin models. DANA engineers can develop and optimize
Cheng, Ming-Te, Zugo, Chris
Technical Paper
Experimental Investigation into Modulated Aeroacoustic Cabin Noise arising from Unsteady Flow Conditions2025-01-0029To be published on 05/05/2025
The unsteady wind conditions experienced by a vehicle whilst driving on the road are different to those typically experienced in the steady-flow wind tunnel development environment, due to turbulence in the natural wind, moving through the unsteady wakes of other road vehicles and travelling through the stationary wakes generated by roadside obstacles. This paper presents an experimental approach using a large SUV-shaped vehicle to assess the effect of unsteady wind on the modulated noise performance, commonly used to evaluate unsteady wind noise characteristics. The contribution from different geometric modifications were also assessed. The approach is extended to assess the pressure distribution on the front side glass of the vehicle, caused by the aerodynamic interactions of the turbulent inflow in straight and yawed positions, to provide insight into the noise generation mechanisms and differences in behaviour between the two environments. The vehicle response to unsteady wind
Jamaluddin, Nur Syafiqah, Oettle, Nicholas, Staron, Domenic
Technical Paper
Multi-Method Approach for car tailgate electric telescopic rod Noise: Detection, Characterization, and Prediction2025-01-0038To be published on 05/05/2025
As the automotive industry moves towards greater intelligence, electric tailgate systems have seen widespread adoption, featuring remote control, obstacle detection, and intelligent opening functions that significantly enhance the user experience. The electric telescopic rod, as a key actuator, has drawn attention for its structural and transmission design. However, studies have shown that during actual operation, various noise issues arise with electric telescopic rods, affecting the sound quality and smoothness of the tailgate's opening and closing. This paper presents a noise detection and analysis study based on a bench test platform for a specific model of electric telescopic rod. Using a microphone to capture noise signals, three main types of noise were identified: high-frequency electromagnetic noise, low-frequency impact noise, and periodic structural noise. The study accurately detects high-frequency electromagnetic noise using wavelet packet energy feature extraction
Fan, Sibei, Wang, Siling, Zhu, Zhehui, Li, Lei, Qin, Jiade, Meng, Dejian, Pei, Kaikun
Technical Paper
A Comparative Analysis of Fault Diagnosis by vibration signals for Critical Gear Components in Electric Vehicle Motor Testing Machines Using Machine Learning Algorithms2025-01-0040To be published on 05/05/2025
Electric vehicles (EVs) represent the future of the automobile industry, with the drive motor being a crucial component in modern EVs. To ensure optimal performance, a motor testing machine is used to verify the essential parameters of these electrical motors. This machine regularly evaluates electric motor characteristic curves and their electromagnetic behavior under different conditions. However, it has been observed that flaws in the testing machine's helical gear arrangement frequently cause malfunctions and suboptimal performance, affecting the efficiency of the electric vehicle production line. This research project aims to improve the motor test bench apparatus by modifying critical design parameters using machine learning and vibration signal analysis methods. Vibration signals are recorded at various gear settings, and statistical features are extracted from these signals. These signals are then classified using classifiers such as Naive Bayes and Decision Trees. Machine
S, Ravikumar, Sharik, N, Syed, Shaul, V, Muralidharan, D, Pradeep Kumar
Technical Paper
Pass-by noise comparison of two test facilities with vehicles operating in electric mode2025-01-0005To be published on 05/05/2025
Outdoor test facilities for light vehicle exterior noise regulatory measurement need to have surfaces certified to meet ISO 10844. A recent study considered plug-in-hybrid vehicles operating purely in electric mode to compare results at two facilities, one in Japan and in the U.S. This emphasizes the pavement contribution. Overall results are generally similar, with a few differences which are discussed.
Sorenson, Steve, Shao, Guangxin
Technical Paper
Identification and Analysis of Aerodynamic Sound Sources on the External Surface of an SUV2025-01-0033To be published on 05/05/2025
Currently, effective methods for analyzing the aerodynamic sound sources of Sport Utility Vehicles (SUVs) are still under development, and the relationship between sound sources and flow dynamics is not yet fully understood. This study presents a method for identifying multi-frequency sound dipole sources within the near-wall flow field by analyzing the relationship between unsteady flow field properties and dipole sources, thereby addressing the complex characteristics of aerodynamic sound sources on vehicle surfaces. Wind tunnel tests, along with full-scale (1:1) Large Eddy Simulation (LES) were conducted on a real SUV. The identification method was applied to analyze the location and magnitude of sound sources near the vehicle's surface. The results, validated using Acoustic Perturbation Equations (APE), indicated that the dipole sources are primarily distributed around the windward side of the front wheels, the side of the front headlights, the A pillar-rearview mirror-front side
Zhang, Hao, Jia, Qing, Wang, Yigang
Technical Paper
Reducing LiDAR Cabin Noise with Damped Elastomers: a Novel Method for Predicting Performance and Durability2025-01-0114To be published on 05/05/2025
Mechanical LiDAR units utilize spinning lasers to scan surrounding areas to enable limited autonomous driving. The motors within the LiDAR modules create noise that can leak into the cabin of a vehicle. Decoupling the module from the body of the vehicle with highly damped elastomers can reduce the acoustic noise in the cabin and improve the driving experience. Damped elastomers work by absorbing the vibrational energy and dispelling it as latent heat, which creates challenges in an unpredictable automotive environment. Throughout the development process with vehicle OEMs and LiDAR ODMs, highly damped elastomers were able to effectively reduce the noise created by the scanning LiDAR modules in a laboratory environment. It was unproven that these elastomers would be as effective in extreme heat, cold, or humid environments. Extensive bench and vehicle tests were conducted, but confidence was low without a model to predict behavior at edge-cases. By creating a unique test method to model
Russell, Casey, Masterson, Peter, O'Connell, Kerry
Technical Paper
Pass-by Noise Contribution Analysis of an Agricultural Tractor2025-01-0134To be published on 05/05/2025
There is an increasing effort to reduce noise pollution across different industries worldwide. From a transportation standpoint, pass-by regulations aim to achieve this and have been implementing increasingly stricter emissions limits. Testing according to these standards is a requirement for homologation but does little to help manufacturers understand why their vehicles may be failing to meet limits. Using a developed methodology such as Pass-by Source Path Contribution (SPC, also known as TPA) allows for identification of dominant contributors to the pass-by receivers along with corresponding acoustic source strengths. This approach is commonly used for passenger vehicles, but impractical for off-highway applications, where vehicles are often too large for most pass-by-suitable chassis dynamometers. A hybrid approach is thereby needed, where the same techniques and instrumentation used in the indoor test are applied to scenarios in an outdoor environment. This allows for
Freeman, Todd, Engels, Bret, Thuesen, Ben
Technical Paper
Research on Clustered Multi-channel Active Noise Control System in Car2025-01-0016To be published on 05/05/2025
In order to solve the problem of intermittent engine intervention during charging and discharging of diesel-electric hybrid vehicles, this paper proposes a semi-coupled cluster control strategy with better comprehensive performance based on the traditional multi-channel Active Noise Control (ANC) system and the advantages of centralized control strategy and decentralized control strategy. Compared with the centralized control strategy, the computational cost of the cluster control strategy is reduced by about 50%, and the noise attenuation performance is comparable to that of the centralized control strategy. Compared with the decentralized control strategy, the stability is obviously better, and the noise reduction effect is outstanding. Based on the MATLAB simulation platform, a variety of cluster control strategies and traditional control strategies in the vehicle are compared and analyzed, and the road test experiments of a range-extended electric vehicle are carried out under its
Deng, Huiping, Lu, Chihua, Chen, Wan, Liu, Zhien, Chen, Pian, Dou, Sirui, Sun, Menglei
Technical Paper
Acoustic characterization of AC motor using sound intensity in non-anechoic laboratory environments2025-01-0010To be published on 05/05/2025
Sound power is commonly used metric to quantify acoustic sources like AC motor in electrified powertrain. This testing is often performed in an anechoic environment to create free-field conditions around the unit. To eliminate the influence of extraneous noise sources, the anechoic facilities must be further isolated from driver and absorber dynamometers. These dynamometers are needed for running the AC motors in the desired speed and load conditions. For early detection of potential issues, it is advantageous to have the capability for engineers to conduct acoustic tests in standard laboratory environments. These may include non-acoustically treated rooms, presence of extraneous noise sources (e.g., driver and absorber dynos), etc. In such environments, sound intensity-based sound power determination methods could be utilized. The sound intensity-based approach is covered in ISO 9614 standard. The norm is to sweep an intensity probe on a sound source in constant speed condition to
Kumar, Aditya, Ippili, Rajani
Technical Paper
Application of blocked force methodology to an electrified beam axle from a medium-duty truck in vehicle and in a dynamometer test cell2025-01-0054To be published on 05/05/2025
The recent shift in propulsion choice away from internal combustion engines has increased the relevance of sound and vibration from electric motors and gearboxes. Electrified beam axles require different metrics from conventional beam axles for noise and vibration because they have multiple sources of vibration energy, including an electric motor and sometimes multiple reduction gearsets. They also require different metrics from electric drive units because they have stiff suspension connections and lack significant isolation. Blocked force is a good candidate because it can completely characterize the vibration energy transmitted into a receiver and is especially useful because it is theoretically independent of the vehicle-side structure. While the blocked force methodology is not new, its application to beam axles is relatively unexplored in the literature. This paper demonstrates a case study of blocked force measurement of an electrified beam axle from a battery electric medium
Shaw, Matthew D, Grimmer, Michael J
Technical Paper
Assignment Criteria for Function Allocation to Commercial Aviation System Security Domains2025-01-0156To be published on 05/02/2025
Aircraft cabin management is characterized by operational and business processes. Both are defined as a logical sequence of activities that occur during the flight. While the operational process includes activities to ensure flight safety, such as take-off, cruise and landing, the business process activities are related to adding value to the customer, i.e. the passenger. They are to be certified by the authority as a part of the aircraft type certification. These processes are defined by the airline and are described as part of the airline’s business model. While the scope of operational processes for passenger safety within the aircraft cabin should remain as unchanged as possible, the increasing competitive pressure on airlines is leading to a constantly rising number of services in the cabin. To prevent compromising cabin safety from increased cabin crew workload during the cruise phase, there is a growing trend toward digitizing operational and business processes. The digitized
Hintze, Hartmut, Blecken, Marvin, God, Ralf, Pereira, Daniel
Technical Paper
Integrating for Safety – A Proposed Approach to the Integration of Propulsion Battery Systems in Hybrid Electric Aviation2025-01-0148To be published on 05/02/2025
In the last year we have witnessed a notable surge in the designs and in the guidance material for electric and hybrid aircraft. FAA and EASA have continued to evaluate the safety of Propulsion Battery Systems (PBS), with a focus on thermal runaway containment testing. As a result, a harmonization white paper was issued to provide a certification path for Thermal Runaway (TR) Hazards, followed by an EASA certification memorandum on the acceptable approaches for the certification of Electric/Hybrid Propulsion Systems (EHPS). And just recently, an FAA Advisory Circular (draft) was issued for the “powered-lift” aircraft that feature these propulsion battery systems. In spite of the advances made by electric/hybrid aircraft manufacturers and the aviation authorities, there is still a missing piece of the puzzle. Mainly, we are still not confident in our ability to properly integrate the PBS into the EHPS architecture, in such a way where safety is never compromised, no matter the hazard
Hanna, Michael, Walker, Cherizar
Technical Paper
Innovative High-Performance Active Dampers for Effective Mitigation of Helicopter Main Rotor Vibrations2025-01-0163To be published on 05/02/2025
Helicopter vibrations, primarily generated by the main rotor-gearbox assembly, are a major source of concern due to their impact on structural integrity, cockpit instrument durability, and crew comfort. These vibrations are mainly transmitted through the gearbox’s rigid support struts to the fuselage, leading to increased cabin noise and potential damage to critical components. This paper presents a solution for vibration mitigation which involves replacing traditional gearbox support struts with low-weight, high-performance active dampers. Developed by Elettronica Aster S.p.A., these active dampers are designed as electro-hydraulic actuators embedded within a compliant structure. The parallel nested configuration of the system enables high power densities and effective vibration control, significantly reducing the transmission of harmful vibrations to the fuselage. The comprehensive model-based design process is detailed, describing the development and use of a high-fidelity physics
Bertolino, Antonio Carlo, Sorli, Massimo, Porro, Paolo Giovanni, Galli, Claudio
Technical Paper
Determining Worst-Case Execution Time Bounds for Multi-core Processors2025-01-0155To be published on 05/02/2025
Demonstrating deadline adherence for real-time tasks is a common requirement in all safety norms, including ISO 26262 and DO-178C. Timing verification has to address two levels: the code level (worst-case execution time) and the scheduling level (worst-case response time). Determining which methodology is suited best depends on the characteristics of the target processor. All contemporary microprocessors try to maximize the instruction-level parallelism by sophisticated performance-enhancing features that make the execution time of a particular instruction dependent on the execution history. On multi-core systems, the execution time additionally is influenced by interference effects on shared resources caused by concurrent activities on the different cores, which are not controlled by the scheduling algorithm. In the avionics domain, the new FAA AC 20-193 / EASA AMC 20-193 guidance documents formalize predictability aspects of multi-core systems and derive adequate measures for timing
Kaestner, Daniel, Gebhard, Gernot, Huembert, Christian, Pister, Markus, Wegener, Simon, Ferdinand, Christian
Technical Paper
A New Test Rig for Electrically Actuated Landing Gear and Brake of a Small Transport Aircraft2025-01-0161To be published on 05/02/2025
Performing highly representative tests of aircraft equipments is a critical feature for gaining utmost confidence on their ability to perform flawlessly in flight under the entire spectrum of operating conditions. This can also contribute to accelerate the certification process of a new equipment. A research project (E-LISA) was performed in recent years, as part of the european funded Clean Sky 2 framework, with the objective of building an innovative facility for testing an electrically actuated landing gear and brake for a small air transport. The project eventually led to the development and construction of an Iron Bird able to reproduce in a realistic and comprehensive way a full variety of landing test cases consistent with certification specifications and landing histories available in the repository of the airframer. The Iron Bird that was eventually developed is a multi-functional intelligent and easy reconfigurable facility integrating hardware and software allowing to
De Martin, Andrea, Bertolino, Antonio, Jacazio, Giovanni
Technical Paper
Enhancing Airworthiness Security: SysML-Based Approach to Modelling Security Scope Definitions2025-01-0172To be published on 05/02/2025
Airworthiness certification of aircraft requires an Airworthiness Security Process (AWSP) to ensure safe operation under potential unauthorized interactions, particularly in the context of growing cyber threats. Regulatory authorities mandate the consideration of Intentional Unauthorized Electronic Interactions (IUEI) in the development of aircraft, airborne software, and equipment. As the industry increasingly adopts Model-Based Systems Engineering (MBSE) to accelerate development, we aim to enhance this effort by focusing on security scope definitions – a critical step within the AWSP for security risk assessment that establishes the boundaries and extent of security measures. However, our findings indicate that, despite the increasing use of model-based tools in development, these security scope definitions often remain either document-based or, when modeled, are presented at overly abstract levels, both of which limit their utility. Furthermore, we found that these definitions
Hechelmann, Adrian, Mannchen, Thomas
Technical Paper
The Why of Development Assurance2025-01-0154To be published on 05/02/2025
In the domain of aircraft certification, Development Assurance is what some would call a useful tool to gain confidence in the development of complex systems, and what others would call a necessary evil. But what does it actually do? Why is it necessary for certification of modern aircraft? What, epistemologically, does it bring to the table? This paper aims to show why development assurance activities, at all levels from aircraft to item, close the epistemological holes created when complex systems are chosen for implementation. It will map the different sources and types of uncertainty encountered in system verification and explain how each type is dealt with within a certification context, working from simple mechanical systems up to complex and highly integrated systems using software and airborne electronic hardware and beyond. It will show that Development Assurance, far from being an arbitrary set of activities, systematically brings personal and corporate expertise to bear to
Laflin, Cory R.
Technical Paper
Image Processing-Based Chip Detection by KIZKI Algorithm and Its Optimization2025-01-0168To be published on 05/02/2025
The process of producing aircraft parts involves the drilling of aluminum alloys. This creates a large amount of chips, which are removed using air, but sometimes they still remain within the holes. This is checked by inspectors through visual inspection. However, the quality of human inspection varies based on skill level and fatigue. Thus, image-based inspection should be used to stabilize and further improve inspection quality. This study aims to build a framework for chip detection based on image processing. Taking into account on-site implementation, the system must have low installation and running costs and be standalone. Therefore, we adopt the KIZKI algorithm, which satisfies these conditions. KIZKI means awareness in Japanese. This is a model of human peripheral vision and saccades. It does not require training like AI and can achieve high-speed and high-performance detection using a low-performance computer. In other words, there is no need for a computer with an expensive
Iinuma, Marin, Sato, Junya, Tsuji, Masahiko
Technical Paper
Verification Methods for AS5653 Network Controller, Network Terminal, and Switch Physical LayerAS6260 (Current)04/25/2025
This document was prepared by the SAE AS-1A2 Committee to establish techniques for verifying that Network Controllers (NCs), Network Terminals (NTs), switches, cables, and connectors comply with the physical layer requirements specified in AS5653B. Note that this verification document only verifies the specific requirements from AS5653B and does not verify all of the requirements invoked by documents that are referenced by AS5653B. The procuring authority may require further testing to verify the requirements not explicitly defined in AS5653B and in this verification document.
AS-1A Avionic Networks Committee
Technical Standard
Test Procedures for Electric Vehicles to Determine Charging PerformanceISO/SAE 12906 (Current)04/23/2025
This document specifies test procedures to determine the charging performance of electric vehicles. This document facilitates clear and consistent comparisons of realistic charging capabilities of electrically propelled vehicles (EVs) via commercially available electric vehicle supply equipment. It provides details about test conditions, test methods, and test processes derived from typical use cases. Furthermore, it specifies requirements regarding the information for the vehicle operator. This document is applicable to EVs, including plug-in hybrid EVs. This document does not provide requirements for mopeds and motorcycles. Unless specified otherwise, all test procedures can be applied to AC, DC, or wireless charging methods.
Hybrid - EV Committee
Recommended Practice
Dynamic Analysis of Intake and Exhaust Valve Motion in a High-Performance 4-Stroke Engine. Part1 - Experimental Measurement of Valve Motion Using a High-Frequency Laser Sensor2024-32-008304/18/2025
The motion of the intake and exhaust valves plays a pivotal role in determining operational efficiency and performance, especially in high-specific power 4-stroke engines. At high rpm levels, the dynamic behavior of the valve may deviate from the kinematic model established during the design phase. This discrepancy arises due to the high accelerations and forces to which the valve and other components of the valvetrain system are subjected. Notably, under such conditions, the valve may detach from the cam profile at the conclusion of the opening stroke and can exhibit a bouncing behavior during the closing stroke. Moreover, the elasticity of all valvetrain system elements introduces additional complexities. Factors such as timing chain elongation, camshaft carrier deformation, and valve stem compression can contribute to a deviation in phase compared to the initially defined kinematics. Within this context, the direct measurement of the valves motion represents fundamental information
Grilli, Niccolò, Romani, Luca, Raspanti, Sandro, Bosi, Lorenzo, Ferrara, Giovanni, Trassi, Paolo, Fiaschi, Jacopo, Guarducci, Edoardo
Technical Paper
Test Method for Catalytic Carbon Brake Disk OxidationAIR5567A (Current)04/14/2025
The scope of the test method is to provide stakeholders including fluid manufacturers, airport operators, brake manufacturers, aircraft constructors, aircraft operators and airworthiness authorities with a relative assessment of the effect of deicing chemicals on carbon oxidation. This simple test is only designed to assess the relative effects of runway deicing chemicals by measuring mass change of contaminated and bare carbon samples tested under the same conditions. It is not possible to set a general acceptance threshold oxidation limit based on this test method because carbon brake stack oxidation is a function of heat sink design and the operating environment.
A-5A Wheels, Brakes and Skid Controls Committee
Information Report
Drive Quality Evaluation for Chassis Dynamometer and On-Road TestingJ2951_202504 (Current)04/14/2025
This SAE Recommended Practice establishes uniform procedures for evaluating conformity between the actual and target drive speeds for chassis dynamometer and on-road testing utilizing standard fuel economy/energy consumption and emissions drive schedules.
Light Duty Vehicle Performance and Economy Measure Committee
Recommended Practice
Automatic Emergency Braking (AEB) System Performance TestingJ3087_202504 (Current)04/14/2025
This document describes an SAE Recommended Practice for Automatic Emergency Braking (AEB) system performance testing which: Establishes uniform vehicle level test procedures Identifies target equipment, test scenarios, and measurement methods Identifies and explains the performance data of interest Does not exclude any particular system or sensor technology Identifies the known limitations of the information contained within (assumptions and “gaps”) Is intended to be a guide toward standard practice and is subject to change on pace with the technology Focuses on “Vehicle Front to Rear, In Lane Scenarios” expanded to include additional offset impacts This document describes the equipment, facilities, methods, and procedures needed to evaluate the ability of Automatic Emergency Braking (AEB) systems to detect and respond to another vehicle, in its forward path, as it is approached from the rear. This document does not specify test conditions (e.g., speeds, decelerations, clearance gaps
Active Safety Systems Standards Committee
Recommended Practice
Assessment of Aircraft Wheel Sealing SystemsARP5146 (Current)04/11/2025
This SAE Aerospace Recommended Practice (ARP) is intended to provide guidance on verifying the integrity of inflation pressure sealing systems of aircraft wheel/tire assemblies.
A-5A Wheels, Brakes and Skid Controls Committee
Recommended Practice
Optimization of the Numerical Spray Modeling for Polyoxymethylene Dimethyl Ethers for Combustion Prediction in CONVERGE2025-01-502604/03/2025
Different approaches are undertaken to mitigate the impact of the transport sector on climate change. Alongside electrifying powertrains, sustainable e-fuels such as polyoxymethylene dimethyl ethers (OME) are considered a promising bridging technology for different applications. However, this requires that the engines are optimized for the new fuels. Accordingly, this study aims to optimize the numerical spray modeling of OME in CONVERGE. Based on the KH–RT break-up model, the spray simulations of three different commercial injectors for heavy-duty applications are analyzed regarding the predictability of the liquid and gaseous penetration lengths and the total simulation time. A sensitivity analysis is conducted for the turbulence model, mesh size, and spray parameters prior to optimizing the spray model and validating it with experimental results. While each parameter individually influences the different phases of the injection event, the sensitivity analysis reveals that the break
Zepf, Andreas, Härtl, Martin, Jaensch, Malte
Technical Paper
Research on Seakeeping Performance of Amphibious Rescue Vehicle Based on CFD2025-01-879504/01/2025
Amphibious vehicles are widely used in civil and military scenarios due to their excellent driving performance in water and on land, unique application scenarios and rapid response capabilities. In the field of civil rescue, the hydrodynamic performance of amphibious vehicles directly affects the speed and accuracy of rescue, and is also related to the life safety of rescuers. In the existing research on the hydrodynamic performance of amphibious vehicles, seakeeping performance has always been the focus of research by researchers and amphibious vehicle manufacturers, but most of the existing research focuses on the navigation performance of amphibious vehicles in still water. In actual application scenarios, amphibious vehicles often face complex water conditions when performing emergency rescue tasks, so it is very important to study the navigation performance of amphibious vehicles in waves. Aiming at the goal of studying the navigation performance of amphibious vehicles in waves
Zhang, Yu
Technical Paper
Development of a Test Course Selection Method for Natural Wind Data Collection on US Public Roads2025-01-878004/01/2025
The automotive aerodynamic development relies on wind tunnel testing and Computational Fluid Dynamics (CFD), where the former provides reliable values to be used for fuel economy calculations, and the latter enables the investigation of flow features responsible for improvement/degradation of the average large-scale performances in terms of aerodynamic coefficients. The abovementioned procedure overlooks a crucial factor however: natural wind. The speed and the direction of natural wind encountered while driving alters the vehicle’s effective yaw angle. Such condition implies that the minimization of the drag coefficient at zero-yaw, commonly performed through wind tunnel and CFD simulations in an industrial context, may not yield real-world optimal shapes. While it is possible to reproduce natural wind-like conditions in a wind tunnel using flaps, for example, the input signal to the flap system must be available beforehand, and such key element is the focus of the present research
Nucera, Fortunato, Onishi, Yasuyuki, Metka, Matt
Technical Paper
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