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Liquefied petroleum gas (LPG) is a popular alternative fuel in the transportation sector as a result of its favorable physical and chemical properties, availability, and relatively lower emissions compared to conventional fuels. However, much of its use is currently in light-duty applications, usually in manifold or port-injected configurations primarily due to their simplicity and ease of conversion. However, there are shortfalls in heavy-duty applications where decarbonization efforts are direly needed. The key reasons for this shortfall in alternative fuel adoption in the heavy-duty sector are the deficit in engine performance when compared to conventional heavy-duty diesel engines and the lack of specialized hardware to bridge this performance gap, for example, direct injectors optimized for LPG fuel operation on large-bore engines. To address this, this study evaluated the performance, emissions, and combustion characteristics of a heavy-duty single-cylinder research engine, the
Fosudo, ToluwalaseWindom, BretOlsen, Daniel
The purpose of this document is to provide a standard for aircraft fuselage markings located at the doors used for ground servicing operations. These markings can be used by all GSE that will dock at the aircraft. These markings may be used for one or several phases of the GSE positioning relative to the aircraft process: GSE alignment during approach, GSE final docking, and GSE auto leveling. It is not the purpose of this standard to describe the different technologies, cameras, or other equipment that can be mounted on GSE to utilize these markings. The aircraft that may use these markings will have a fuselage diameter of 3 m or more.
AGE-3 Aircraft Ground Support Equipment Committee
In electrified drivetrains, lubricants are commonly in contact with the motor and other electrical components as well as the gears and bearings. Copper, present in these electrical components, is susceptible to corrosion by fluids containing active sulfur, which can lead to catastrophic failure of the unit. Lubricating fluids for electric vehicles (referred to as e-fluids) must not cause corrosion and must maintain high performance while having suitable electrical conductivity, material compatibility, and heat transfer properties. We describe a new formulation without active sulfur that has recently entered the market, which can protect against copper corrosion. We show that this e-fluid can provide suitable wear protection under field trial conditions, and that the e-fluid provides improved wear protection in bearing (FE-8) tests compared to a traditional extreme pressure axle fluid (API GL-4). Surface analysis (X-ray photoelectron spectroscopy) measurements of the component surfaces
Hopper, Elizabeth R.Williams, Megan S.Gahagan, Michael
This SAE Aerospace Standard (AS) provides requirements for design and installation of aircraft jacking pad adapters and the mating jack socket interface to permit use of standard jacking equipment to be used in civil and military transport aircraft. The adapter defined herein shall be the key interface between the aircraft and the aircraft jack(s).
AGE-3 Aircraft Ground Support Equipment Committee
This SAE Recommended Practice is intended to establish a procedure to certify the fundamental driving skill levels of professional drivers. This certification can be used by the individual driver to qualify their skills when seeking employment or other professional activity. These certification levels may also be used by test facilities or other organizations when seeking test or professional drivers of various skills. The associated family of documents listed below establish driving skill criteria for various specific categories. SAE J3300: Driving level SAE J3300/1: Low mu/winter driving SAE J3300/2: Trailer towing SAE J3300/3: Automated driving Additional certifications to be added as appropriate. This main document provides: (1) common definitions and general guidance for using this family of documents, (2) directions for obtaining certification through Probitas Authentication®1, and (3) driving level examination requirements.
Driving Skills Standards Committee
Software reliability prediction involves predicting future failure rates or expected number of failures that can happen in the operational timeline of the software. The time-domain approach of software reliability modeling has received great emphasis and there exists numerous software reliability models that aim to capture the underlying failure process by using the relationship between time and software failures. These models work well for one-step prediction of time between failures or failure count per unit time. But for forecasting the expected number of failures, no single model will be able to perform the best on all datasets. For making accurate predictions, two hybrid approaches have been developed—minimization and neural network—to give importance to only those models that are able to model the failure process with good accuracy and then combine the predictions of them to get good results in forecasting failures across all datasets. These models once trained on the dataset are
Mahdev, Akash RavishankarLal, VinayakMuralimohan, PramodReddy, HemanjaneyaMathur, Rachit
Letter from the Guest Editors
Liang, CiTörngren, Martin
This SAE Recommended Practice defines the minimum functional requirements for quick connect couplings used for supply, return, and vapor/emission fuel system connections. This document also defines standard male tube end form dimensions, so as to guarantee interchangeability between all connector designs of the same male tube end form size. This document applies to automotive and light truck applications under the following conditions: a Gasoline and diesel fuel delivery systems or their vapor venting or evaporative emission control systems. b Operating pressure up to 500 kPa, 5 bar, (72 psig). c Operating vacuum down to −50 kPa, −0.5 bar (−7.2 psi). d Operating temperatures from −40 °C (−40 °F) to 115 °C (239 °F). Quick connect couplings function by joining the connector to a mating tube end form, then pulling back to assure a complete connection. The requirements stated in this document apply to new connectors in assembly operations unless otherwise indicated. For service operations
Fuel Systems Standards Committee
This study focuses on the numerical analysis of weather-strip contact sealing performance with a variable cross-sectional design, addressing both static and dynamic behaviors, including the critical issue of stick-slip phenomena. By employing finite element modeling (FEM), the research simulates contact pressures and deformations under varying compression loads, DCE (Door Closing Efforts) requirements, typical in automotive applications. The analysis evaluates how changes in the cross-sectional shape of the weather-strip affect its ability to maintain a consistent sealing performance, especially under dynamic vehicle operations. The study also delves into stick-slip behavior, a known cause of noise and vibration issues, particularly improper/ loosened door-seal contact during dynamic driving condition. This study identifies key parameters influencing stick-slip events, such as friction coefficients, material stiffness, surface interactions, sliding velocity, wet/dry condition
Ganesan, KarthikeyanSeok, Sang HoSun, Hyang Sun
The “Model Architecture and Interfaces Recommended Practice for Ground Vehicle System and Subsystem Dynamical Simulation” defines the architectural structure of a ground vehicle system dynamical model by partitioning it into subsystem models and by defining subsystem interfaces required to enable plug-and-play operation of a dynamical simulation models. All types of ground vehicle were considered in the development of the architecture, such as, passenger cars, light and medium duty trucks, heavy duty tractor trailer trucks, and vehicles/equipment for military, farming, construction, and mining. Versatility of this architectural partitioning is demonstrated by showing how it can be applied to different vehicle configurations. Application examples of architecture are provided for a large number of the publicly known ground vehicle configurations in production, testing, or development. This recommended practice encompasses standards to enable seamless plug-and-play reusability of
Dynamical Modeling and Simulation Committee
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-side mirror-front side
Zhang, HaoJia, QingWang, Yigang
Platform based vehicle development is standardized at John Deere. The challenges of frontloading the integration of individual components within different platforms using predictive methods is key to shortening the development cycle. Components are individually characterized on test benches and results cannot directly be used to evaluate system performance. Invariant characterization is needed instead, which is possible through techniques such as blocked loads estimation. To evaluate the applicability of such methods, the component-based loads and vehicle in-situ operational loads need to be compared. The confident use of these methods for obtaining structural and acoustic loads enables the use of hybrid system models, enhancing early NVH response predictions. The objective of this work was to enable the confident use of test stand measurements in predictive models across various vehicle platforms. This study compares a powertrain characterization in a vehicle against a test stand to
Vesikar, Prasad BalkrishnaEdgington, JasonDrabison II, John
Noise transmission through the vehicle dash panel plays a critical role in isolating passengers from noise sources within the motor bay of the vehicle. Grommets that contain electrical harness routing as well as HVAC lines are examples of dash panel pass-throughs that should be selected with care. Acoustic performance of these components is generally characterized in terms of measured quantities such as noise reduction (NR), sound transmission loss (STL), and insertion loss (IL). These measurements need to be carried out per SAE or ASTM standards in appropriate anechoic or reverberant chambers as this is important for consistency. This work explores an in-situ measurement of the grommet STL performance in the vehicle environment. It utilizes a repurposed vehicle with its cabin retrofitted to serve as an anechoic chamber and its frunk acting as a reverberant chamber. Results of this in-situ measurement are then compared to measurements following industry standards to discuss the
Joodi, BenjaminJayakumar, VigneshChang, MichaelGeissler, ChristianPilz, FernandoConklin, Chris
For mature virtual development, enlarging coverage of performances and driving conditions comparable with physical prototype is important. The subjective evaluation on various driving conditions to find abnormal or nonlinear phenomena as well as objective evaluation becomes indispensable even in virtual development stage. From the previous research, the road noise had been successfully predicted and replayed from the synthesis of system models. In this study, model based NVH simulator dedicated to virtual development have been implemented. At first, in addition to road noise, motor noise was predicted from experimental models such as blocked force and transfer function of motor, mount and body according to various vehicle conditions such as speed and torque. Next, to convert driver’s inputs such as acceleration and brake pedal, mode selection button and steering wheel to vehicle’s driving conditions, 1-D performance model was generated and calibrated. Finally, the audio and visual
Park, SangyoungDirickx, TomKang, Yeon JuneNam, Jeong MinGonçalves, Vinícius Valencia
Rotor skewing is a commonly used technique to mitigate noise and vibration challenges of permanent magnet synchronous motor. The intention of rotor skewing is to minimize targeted electromagnetic forces, thereby enhancing motor NVH performance. However, achieving improved NVH performance may be attainable by merely altering the rotor skew pattern while keeping the summation of radial and tangential electromagnetic forces the same. This research investigates the impact of different rotor skewing patterns on the NVH performance of permanent magnet synchronous motor. With summation of radial and tangential electromagnetic forces remaining the same, four different skew patterns are applied to generate electromagnetic forces across each motor slice. Multi-slice method is used for different skew patterns when applying electromagnetic forces on the motor model. Noise and vibration level will be compared to identify the best skew pattern for proposed motor.
Chen, KeyuWang, WeiMa, CongHartwig, MarcusNarayanan, Arun
The rapid adoption of electric vehicles (EVs) necessitates updates to the automotive testing standards, particularly for noise emission. This paper examines the vehicle-level noise emission testing of a Nikola Class 8 hydrogen fuel cell electric semi-truck and the component-level noise emission testing needed to create a predictive simulation model using Wave6 software. The physical, component-level noise emission testing focused on individual cooling fans in a semi-anechoic chamber to assess their isolated noise contributions. With this data, an initial model was developed using spatial gradient statistical energy analysis, which successfully predicted pass-by noise levels based on varying fan locations and speeds. Real-world pass-by testing confirmed the model's accuracy across different cooling fan speeds. By leveraging advanced simulation techniques, engineers aim to enhance the accuracy and reliability of pass-by noise predictions through cost-effective studies of architectural
Passador, StephenWoo, SangbeomLiu, Ting-WeiDe La Vega Alonso, GerardoKim, James
A proprietary metamaterial has been shown to reduce panel vibration. In this particular case, the metamaterial is designed to be attached to the edge of a glass panel and can reduce panel vibration and noise transmission due to wind or other sources into the vehicle interior. Acoustic transmission loss and panel vibration assessments show the benefit of this approach.
Sorenson, SteveLi, XiaopengMoore, JaimeRobison, Scott
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 limitation, such as bad spatial resolution at the low frequency range, and limited system dynamic range. To improve the performance, three deconvolution methods CLEAN, CLEAN-SC and DAMAS were investigated and applied to identify wind noise sources on a production car in this paper. After analysis of vehicle exterior wind noise sources distribution, correlation analysis between identified exterior noise sources and interior noise were conducted to study their energy contribution to vehicle interior. The results show that the algorithm CLEAN-SC based on spatial source coherence shows the best capability to remove the sidelobes for the uncorrelated wind noise sources, while CLEAN and DAMAS, which are based on point spread functions have definite
He, YinzhiShen, HenghaoWu, YuZhang, LijunYang, ZhigangBlumrich, ReinhardWiedemann, Jochen
High-frequency whine noise in electric vehicles (EVs) is a significant issue that impacts customer perception and alters their overall view of the vehicle. This undesirable acoustic environment arises from the interaction between motor polar resonance and the resonance of the engine mount rubber. To address this challenge, the proposal introduces an innovative approach to predicting and tuning the frequency response by precisely adjusting the shape of rubber flaps, specifically their length and width. The approach includes the cumulation of two solutions: a precise adjustment of rubber flap dimensions and the integration of ML. The ML model is trained on historical data, derived from a mixture of physical testing conducted over the years and CAE simulations, to predict the effects of different flap dimensions on frequency response, providing a data-driven basis for optimization. This predictive capability is further enhanced by a Python program that automates the optimization of flap
Hazra, SandipKhan, Arkadip
This paper discusses a systematic process that was developed to evaluate the acoustic performance of a production dash system. In this case it is for an electric vehicle application. The production dash panel was tested under different configurations to understand the importance of passthroughs in the acoustics of the 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 sound transmission loss. To understand the acoustic strength of different passthroughs and their effects on the overall system, the dash with passthroughs underwent extensive testing. Subsequently, a test procedure using flat panels was developed to quantify the performance of individual passthroughs on a part level. This data can be used by the OEM to develop STL targets that can be considered in the grommet design early in the vehicle development process.
Saha, PranabBaack, GregoryGeissler, ChristianKaluvakota, SrikanthPilz, Fernando
One 1.5L Miller-cycle turbocharged four cylinder gasoline hybrid engine is installed on a certain hybrid vehicle. When accelerating at low to medium speeds with a small throttle, there is a "da da" knocking noise inside the car, which seriously affects the overall sound quality of the vehicle. By analyzing the vibration and noise data of the engine, it was found that the frequency of the abnormal knocking sound is 200-2000Hz, which presents a half order characteristic in the time domain, that is, one knocking occurs when the engine crankshaft rotates twice. Through Hilbert demodulation analysis of the vibration data in the problem frequency range, it was found that the knocking noise was modulated in the frequency domain, with a modulation frequency of half of the crankshaft rotation frequency. By building a fully flexible multi-body dynamic model of a hybrid powertrain and inputting the engine's cylinder pressure excitation, the combustion excitation is coupled with mechanical
Dan, Kong
Squeak and Rattle (S&R) issues present significant challenges in the automotive industry, negatively affecting the perceived quality of vehicles. Early identification of these issues through rigorous testing protocols—such as auditory assessments and dynamic simulations—enables the development of more robust systems while optimizing resource use. Finite Element Method (FEM) simulations are crucial for identifying S&R issues during the design phase, allowing engineers to address potential problems before the creation of physical prototypes. By developing high-fidelity virtual models and accurately simulating flexible connections, these simulations effectively capture rattle effects, enhancing prediction reliability. Traditional snap stiffness calculations typically employ a cantilever-based formulation, which is suitable for simple snap-fit designs but insufficient for more complex geometries that require enhanced stiffness. To address this limitation, the proposed methodology utilizes
Rao, SohanElangovan, PraneshReddy, Hari
Two wheeler is important and essential transportation mode in many of the countries across the globe. Designing a motorcycle with better riding comfort and minimal vibration are thus a major challenge for engineers now a day. Engine and road excitations are two source of vibration acting on motor bike or scooter both. These vibrations are transmitted to the chassis, sub chassis, aesthetic parts and then to the rider and pillion. Unwanted vibrations will create discomfort to the rider/pillion and produce noise. Hence, these need to be minimized. This study is focus on diagnosis and control of output vibration response of sub chassis/aesthetic parts due to engine unbalanced excitation force. There are numerous parameter of motor bike/scooter that governs the vibration response of sub chassis/aesthetic parts. Engine unbalanced inertia force characteristics and their transmission to rider and pillion has been studied and reported here. Environmental benefit demands for a complete noise
Khare, Saharash
New mobility concepts with smart infrastructure have led to enhanced customer driving experience. The potential to develop safe cars with minimal driver intervention is a great need of the future. The cusp for fully autonomous driving has produced much technical talk, which has led to faster transition and adoption. One of the features that global OEMs have tried to focus on, is Human Machine Interface (HMI) solutions, popularly called display screens. The touchscreen HMIs are common in all mid-range budget cars. They offer driver support beyond just streaming music, including inputs for navigation, parking assistance, in-car technologies, Advanced Driver Assistance Systems (ADAS), and infotainment. Poor display screen visibility is a phenomenon observed when a vehicle is driven over different road surfaces. This paper presents a user-centric approach for the right design & development of the HMI for a vibration free driving experience. The mounting strategies for the display screens
Adil, MD ShahzadC M, MithunMohammed, RiyazuddinR, Prasath