Your Destination for Mobility Engineering Resources

This specification covers one type of nickel-aluminum bronze in the form of extruded bars, rods, and tubes up to 4.00 inches (101.6 mm) in nominal diameter, distance between parallel sides, or wall thickness (see 8.5).
AMS D Nonferrous Alloys Committee
This specification covers one type of bronze in the form of round wire 0.500 inch (12.70 mm) and under in nominal diameter (see 8.5).
AMS D Nonferrous Alloys Committee
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
This SAE Recommended Practice (RP) aids in the identification, handling, and shipping of lithium batteries to and from specified locations. It is the specific intent of this RP to identify, utilize, and reference existing U.S. and international hazardous materials (dangerous goods) transportation regulations, which are the only methodologies to be used to establish transportability. It is also the intent of this RP to provide recommendations to be used by service and shipping personnel for the purpose of determining a possibly damaged/defective battery’s transportability. In support of the service and shipping personnel, these recommendations seek to use standard tools of the trade and avoid laboratory-type equipment.
Battery Transportation and Storage Committee
This document presents design and application information which will allow optimized utilization of filter line wire and cable purchased to AS85485. Filter line wire is defined and design information is presented. The electrical and mechanical performance characteristics of the wire, along with recommended harnessing methods and techniques, are also presented.
AE-8A Elec Wiring and Fiber Optic Interconnect Sys Install
This specification establishes the requirements for an expanded polytetrafluoroethylene (ePTFE) in the form of sealing tape, gaskets, or sheets requiring no mixing or curing.
AMS G9 Aerospace Sealing Committee
This specification covers a corrosion-resistant steel in the form of two types of aircraft tubing.
AMS F Corrosion and Heat Resistant Alloys Committee
This document describes a process for use by ADHP integrators of EEE parts and subassemblies (items) that may have been targeted by part manufacturers for other applications. This methodology allows for existing data, such as manufacturer qualification test results, in-service use, and system qualification test data, to meet the application requirement and to identify gaps in data that require additional testing or analysis. This document describes a process to define and accomplish application-specific qualifications that provide confidence to both the ADHP integrators and the integrators’ customers that the item will perform its function(s) reliably in the ADHP application. It does not describe specific tests to be conducted, sample sizes to be used, or results to be obtained.
APMC Avionics Process Management
This specification covers the requirements for an aluminum brazing flux in granular form.
AMS B Finishes Processes and Fluids Committee
Proactive safety and vehicle automation typically requires high energy use from sensors and energy-intensive computing from sensor data processing. For high-quality, reliable perception and localization within a driving environment at the vehicle level, incoming data from multiple sensors need to be fused using advanced computational algorithms, which demand a high compute load. Alternatively, computational offloading of automated driving tasks shifts energy consumption from the vehicle to cloud infrastructure, where renewable energy sources, such as hydropower or solar power, can be utilized more efficiently. Herein, an optimal scheduling strategy for autonomous driving tasks via the cloud layer is formulated as a mixed-integer linear programming (MILP) problem and verified using measurement-informed task graphs. It is shown that cloud-based computational offloading enables energy-efficient operation while maintaining task deadlines to ensure the timely availability of perception and localization information, which is consistent with prior studies in the literature. Simulation results demonstrate that on average, 35.78% of the computational load was offloaded to the cloud, which can achieve significant energy savings for the onboard system. The compute operations achieved an average energy savings of 35.65%, while total system savings ranged from 26.16% to 30.67% under different cloud energy efficiency scenarios, highlighting the advantages of offloading compute-intensive tasks. The framework was further evaluated using multiple directed acyclic graph (DAG) configurations to assess its scalability and adaptability. Critical tasks, such as sensor fusion, were executed exclusively on the vehicle to ensure real-time responsiveness.
Sharma, Sachin, Meyer, Richard, Feinberg, Ben, Asher, Zachary
As part of the dtec.bw MORE project, serial hybrid powertrains featuring alternative combustion regimes, specifically homogeneous reactivity-controlled compression ignition (hRCCI), are under investigation to maximize thermal efficiency while minimizing NOx and soot emissions. The proposed hRCCI concept utilizes dual-fuel stratification, employing early direct injection (DI) of octanol (high-reactivity fuel) alongside port fuel injection (PFI) of ethanol (low-reactivity fuel). While 0D/1D engine modeling is essential for developing predictive powertrain simulation frameworks, conventional models often lack the robustness required to capture the complexities of low-temperature combustion (LTC). This study addresses this limitation by developing a multi-zone “onion skin” quasi-dimensional model. Since for LTC, ignition and heat release rates are highly sensitive to thermal and chemical stratification, capturing these gradients is critical. 3D computational fluid dynamics (CFD) simulations are capable of capturing thermal and chemical stratifications to a high degree of accuracy, whereas 0D simulation models, in general, do not consider them. The primary contribution of this work is the translation of high-fidelity 3D CFD data into a computationally efficient quasi-dimensional environment. A simplified 3D CFD architecture was utilized to map the effects of various operating parameters on mixture distribution. Using these results, a regression learning model was trained to predict octanol and temperature stratification within the combustion chamber. Validation against simulation data demonstrates that this coupled machine learning and multi-zone approach provides a robust, predictive tool for evaluating advanced LTC concepts within larger system-level simulations.
Sundaram, Pravin Kumar, Grundl, Larissa Michaela, Trapp, Christian Thorsten, Tinschmann, Georg
Physical constraints are characterized by vehicle stability boundaries and actuator hardware limits. However, they cannot capture driver perception of vehicle responses or quantify the effects of actuator inputs on vehicle stability. This article proposes a double-envelope coordinated control strategy with subjective–objective consistent stability evaluation for corner-module vehicles. Actuator stability margins are derived from vehicle stability boundaries under four-wheel steering and distributed drive. They are used to prevent vehicle instability in advance by constraining destabilizing actuator inputs. Real-vehicle tests identify driver-perceived boundaries under varying vehicle speeds and road adhesion conditions. Mapping these boundaries to the objective stability index establishes a subjective–objective consistent evaluation. Actuator stability margins and consistent evaluation form a soft envelope, while vehicle stability boundaries and actuator hardware limits define a hard envelope. The resulting double-envelope coordinated control adjusts actuator priorities according to the actuator stability margins and adapts control targets to reflect driver perception. CarSim-Simulink co-simulation and hardware-in-the-loop experiments demonstrate improvements in extreme obstacle avoidance capability and driver handling confidence.
Shi, Wenbo, Ding, Haitao, Xu, Nan, Zhang, Xinjie
This article presents an experimental investigation of off-tracking in a tractor–semitrailer during intersection-type turning maneuvers, which typically involve quarter-circle turning paths at urban junctions. Two coupling configurations are examined: a conventional fifth-wheel coupling (CFWC) and a split fifth-wheel coupling (SFWC). A scaled articulated vehicle prototype is developed to conduct controlled low-speed turning tests across multiple radii representative of intersection maneuvering conditions. The measured trajectories of the tractor and semitrailer are compared with predictions from a previously developed zero-speed kinematic model adapted for the present configuration. Maximum off-tracking is quantified for both coupling systems, and agreement between measured and simulated trajectories is evaluated using a normalized root-mean-square error metric. Results show that the SFWC consistently reduces off-tracking relative to the CFWC across all tested radii, while the kinematic model predicts the measured off-tracking profiles with mean-normalized errors below 0.1. The study is positioned as an experimental assessment of a previously proposed SFWC concept and kinematic formulation, rather than as a new coupling concept or a new modeling method. The findings provide controlled experimental evidence on the influence of coupling configuration on low-speed off-tracking behavior, while the practical implementation of the SFWC is identified as requiring further full-scale mechanical design, articulation limit, and durability studies.
Jogi, Ajith, Chandramohan, Sujatha, Krishnapillai, Shankar
This specification covers a corrosion-resistant steel product in the solution and precipitation heat treated (H1075) condition, 4 inches (102 mm) and under in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This test procedure is intended to apply to hydraulic pump suction filters and strainers used in automotive automatic transmissions that include hydraulic power pumps. The various paragraphs of Section 5 include a variety of tests and alternative tests that are not applicable to all filters and applications, so the engineer must specify which tests are to be performed for a particular application. These test procedures are intended to evaluate filter functional performance characteristics only; durability is not evaluated under this standard. Filter design requirements must be specified by the engineer on the filter assembly drawing, an applicable engineering specification, or summarized on an application data sheet similar to that found in this recommended practice. See Figure 6. Pressure circuit filters, both barrier and system contamination control types, are not covered under this standard. They are similar in design and construction to filters used in many hydraulic and lubricating applications. Testing for pressure filters is covered by the ISO and SAE standards listed in Section 2.
Automatic Transmission and Transaxle Committee
With the rising pressure of a global energy transition to cleaner energy systems, the transportation sector faces a challenge in maintaining its current structure and adapting to all the required changes. Dual-fuel technology emerges as a promising alternative to keep the viability of the sector while utilizing environmentally friendly fuels alongside traditional hydrocarbons, without deep structural changes in the current framework. This work investigates the impact of the use of methane gas coupled with diesel fuel, specifically focusing on its influence on the ignition delay time (IDT) in a dual-fuel combustion setting. The investigation employed the Advanced Fuel Ignition Delay Analyzer (AFIDA), a constant-volume combustion chamber capable of automatically measuring multiple samples in a single run. Methane gas was introduced into the chamber at molar concentrations of 1%, 2%, and 3% and at initial pressures of 5 and 10 bar, with temperature values ranging from 653 to 723 K. With the same amount of diesel being injected for all experiments, it was possible to replace up to 40% of the total energy release with methane during the combustion process. Compared to pure diesel, the IDT values of the methane–diesel mixtures were only affected in low-temperature settings. At higher temperatures, the IDT values remained largely consistent with those of pure diesel, suggesting that higher substitution ratios of methane are feasible without compromising the ignition delay. This work also uncovered that the percentage of energy replaced by methane does not have a direct correlation with IDT or peak pressure values.
Pacheco Virginio, Thiago, Eraqi, Basem, Sakleshpur Nagaraja, Shashank, Sarathy, S. Mani
Total Cost of Ownership (TCO) is a key metric in commercial vehicle purchase decisions and evaluation of advanced technologies such as battery electric and fuel cell vehicles (BEVs and FCEVs). Inputs derived from aggregate operating data, such as annual miles of travel and average fuel efficiency, as used in most TCO tools, may be inadequate for assessing technologies in specific applications. To provide more accurate estimates, the Transportation Technology Total Cost of Ownership (T3CO) model integrates vehicle simulation using the Future Automotive Systems Technology Simulator (FASTSim™). T3CO incorporates opportunity costs that may arise when technologies do not provide equivalent performance to conventional powertrains, such as reduced payload capacity and added downtime for more frequent and longer duration refueling. While past analyses used single duty cycles representative of average daily distance and energy per mile, fueling dwell time is nonlinear with respect to daily energy requirements and may not be captured with representative cycles. In this study, T3CO is applied to real-world operational data collected over 32 months from conventional Class 5 work trucks in three fleets, covering a variety of use cases and variability in daily demands. Diesel, BEV, and FCEV powertrains were simulated over the full data set, for a total of 1,986 vehicle days and 145,919 miles each. Analysis of duty cycle variability results in up to a 61% difference in fleet-level weighted average TCO compared to analysis over a single representative day. While diesel and FCEV TCO results are sensitive to fuel cost, BEV TCO is sensitive to the downtime from occasional daytime charging present in the total life cycle and not reflected in a subset “representative day.” For the studied fleets, these findings alter conclusions about the relative cost-effectiveness of new technology options at both the vehicle and fleet levels.
Birky, Alicia, Panneer Selvam, Harish, Sigler, Cory, Carow, Kyle, Miller, Eric, Ortmann, Walt, Tascillo, Mark
This article presents a hybrid battery management system for unmanned surface vehicles, integrating three operational modes: solar-to-cell balancing, capacitive balancing, and solar-to-pack charging—within a shared architecture. The system prioritizes solar-to-cell balancing when solar energy is available, capacitive balancing when charging without solar input, and solar-to-pack charging when cells are balanced. This approach eliminates additional hardware by utilizing a shared-hardware architecture. A 14.8 V battery pack composed of four 3.7 V Li-ion modules was simulated and prototyped to validate the system. Experimental and simulation results confirm improved cell balancing, reduced state-of-health deviation, and extended operational time, demonstrating superior performance, sustainability, and adaptability over conventional battery management system solutions for unmanned surface vehicles and similar platforms.
Blair, Raymond, Kyger, Kenton, Duan, Chen
Concealed HVAC air duct and vent systems are increasingly adopted in modern electric vehicles due to their improved cockpit integration capability and compatibility with intelligent airflow management strategies. However, the complex internal geometry and distributed airflow characteristics of concealed vent configurations often introduce increased broadband aeroacoustic noise, particularly at middle and high frequencies, where cabin masking effects are significantly reduced in electric vehicles. In this work, a high-fidelity aeroacoustic methodology based on the Lattice Boltzmann Method (LBM) was applied using PowerFLOW to investigate concealed HVAC vent aeroacoustic mechanisms and design sensitivities. Detailed vent geometry was preserved using the Precise Wrap tessellation approach, while acoustic porous media and wall absorption treatments were incorporated to represent the acoustic behavior of foam materials inside the duct system. Numerical predictions were correlated with semi-anechoic chamber measurements under representative test conditions. The study hypothesized that concealed vent cavity structures and flap–louver interaction dominate broadband aeroacoustic generation above 1000 Hz and that high-fidelity LBM simulation with detailed geometric representation can capture these mechanisms within engineering-level prediction accuracy. Good agreement between simulation and experiment was achieved for both overall sound pressure level (SPL) and narrow-band spectrum distribution. The average OASPL deviation was approximately 2 dB, with a maximum deviation of 3.3 dB among the investigated microphone locations, while the narrow-band SPL deviation mainly remained within 5 dB for frequencies below 5000 Hz. The predicted broadband hump near 1500–2500 Hz was shown to correlate strongly with vent cavity characteristics and flap–louver interaction. Flow field analysis identified pronounced vortex shedding within concealed vent branches and localized flow separation near the flap leading edge and louvers. Parametric investigations further demonstrated that suppressing leading-edge vortex impingement reduced the broadband hump near 1500 Hz, while removal of flap–louver interaction significantly reduced high-frequency broadband noise above 1500 Hz. The present work demonstrates that high-fidelity LBM simulation can provide reliable engineering-level aeroacoustic prediction for concealed HVAC vent development during the early design stage. The study also provides practical design guidance for developing low-noise concealed HVAC systems for electric vehicle applications.
Hu, Liangbo, Xiong, Fei, Pan, Aicheng, Song, Jinxiang, He, Jianfeng
As the technology of electric vehicles (EVs) continues to mature, in-wheel motors (IWMs), as an innovative drivetrain technology, offer significant advantages in enhancing vehicle performance, simplifying design, and optimizing space utilization. It is gradually becoming a key direction in the technological development of EVs. Therefore, this article aims to provide a comprehensive review of IWM drive techniques and recent developments for automotive applications. This article first reviews the historical development of IWMs, followed by an overview of current motor configurations categorized by air-gap flux direction and topological structure, along with a comparative analysis of their performance characteristics. Following this, the coupling dynamic effects between IWMs and overall vehicle dynamics are systematically analyzed, specifically distinguishing between internal and external vibration excitation sources. In terms of control strategies for IWM-driven EVs, recent literature is extensively surveyed across three critical dimensions: noise, vibration, and harshness (NVH), vehicle stability, and energy economy. Finally, based on the current state of the art, the review identifies and discusses future trends in IWM technology aimed at further elevating overall vehicle performance. Ultimately, this article is intended to serve as a valuable reference guide for researchers and engineers engaged in the development of IWMs and related EV technologies.
Guo, Ruixin, Zhu, Yueying, Xing, Chao, He, Yang, Lin, Yier
Automotive door latches play a crucial role in occupant safety and user experience. The mechanisms utilized as latching systems in automotive doors are designed to hold the doors in a closed position relative to the body of a vehicle and can be grouped into three major categories: hood/frunk latches, lift gate latches, and side door latches. These mechanical systems vary in design across vehicle models, but all must withstand harsh environmental conditions, including water intrusion. Therefore, their requirements and validations include rigorous testing that ensures the continued functionality of the device after being subjected to extreme environmental conditions, such as cold, heat, and humidity. Rainfall in winter months leads to ice storms where water freezes instantly upon contact with cold surfaces, leading to ice formation on structures. In some cases, water can penetrate latch systems, freezing the latch systems with the risk of potentially making them inoperable. Currently, validation methods require physical parts for testing, meaning that to assess the risks, it is necessary to advance the development of the product to its final stages to have a prototype that adequately represents the design intention of the automotive latch. This study employs smoothed particle hydrodynamics (SPH), a mesh-free numerical method well suited for analyzing complex fluid behaviors. By leveraging Simcenter Nanofluid, an SPH-based simulation tool accelerated by graphics processing unit (GPU) computing, we achieve high-fidelity fluid simulations with reduced computational time, enabling rapid iteration during design cycles. This paper presents a comparative analysis of physical water spray tests and virtual simulations conducted using Simcenter Nanofluid. Correlating simulation outcomes with test data validates the model’s accuracy. Design changes informed by this insight help the development cycle by identifying opportunities to mitigate water ingress and enhance system robustness.
Chaudhari, Abhijit Digambar, Srikanth, Praveen, Takabi, Behrouz, Calamaco, Eli, Estrada, Ignacio, Huerta, Sergio
High exhaust gas recirculation (EGR) rates in dedicated hybrid engines (DHEs) cause combustion instability and fuel economy degradation. This study investigates a 2.0L turbocharged DHE with a high-tumble combustion system optimized by computational fluid dynamics (CFD) simulation. At the brake thermal efficiency (BTE) operating point (2750 r/min, brake mean effective pressure [BMEP] 11 bar), engine bench tests evaluated the effects of three ignition energy levels (120 mJ, 150 mJ, 200 mJ) and two spark plug configurations (1.1 mm nickel alloy and 0.7 mm pin-to-pin iridium) on combustion characteristics, fuel economy, the misfire-limited EGR rate (hereinafter the EGR misfire limit), and engine-out emissions. Results show that above 23% EGR, intake condensate weakens ignition and destabilizes combustion. Raising ignition energy to 200 mJ extends the EGR misfire limit from 23% to 28%, shortens ignition delay (CA0-10) and combustion duration (CA10-90) by 4.5°CA and 2.8°CA and reduces BSFC by 3.2 g/kWh. The 0.7-mm iridium plug outperforms the 1.1-mm nickel alloy plug above 27% EGR: CA0-10 and CA10-90 shorten by 2.9°CA and 2.5°CA, the EGR misfire limit extends by 0.5 percentage points, and BSFC improves by 0.9 g/kWh. The combined optimization extends the EGR misfire limit to 28.5% with a cumulative BSFC reduction of 4.5 g/kWh. HC emissions decrease with reduced spark plug gap, while NOx and CO remain insensitive to the ignition strategy. The coupled optimization of high-energy ignition and small-gap spark plug effectively overcomes ignition degradation under high EGR. The reduced breakdown voltage of the small gap and the sufficient energy reserve of high-energy ignition form a synergistic effect, providing quantitative design guidance for ignition systems in next-generation high-efficiency DHEs.
Wang, Peng, Ren, Siming, Cong, Rizhen, Deng, Xiaorong, Liu, Zonghui, Zhu, Yunfeng, Li, Hongzhou, Yan, Pingtao
2025-2026 Reviewers
Onori, Simona