Browse Topic: Maintenance and Aftermarket

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An Architecture for Vehicle Diagnostics in Software-Defined Vehicles2025-01-0280To be published on 07/02/2025
Vehicles are evolving into Software-Defined Vehicles. The increasing use of automotive High Performance Computers (HPCs) provides more computing power and storage resources in vehicles. This opens possibilities to use more in-vehicle software. However, it also leads to challenges for vehicle diagnostics. Today's diagnostic approaches, based on Diagnostic Trouble Codes (DTCs), are not suitable for software on HPCs. For example, this software is highly variable and updated over time, so predefined DTCs are not dynamic enough. This introduces a degree of ambiguity into the diagnostic processes. Additional diagnostic data are required. In the Cloud, observability approaches are becoming widely used for software. Observability involves examining the availability and performance of an entire software system. To detect failures early, observability data, such as logs, metrics, and traces, are used. This is of interest for vehicle diagnostics as new diagnostic approaches are needed to
Bickelhaupt, Sandra, Hahn, Michael, Weyrich, Michael, Morozov, Andrey
Technical Paper
Requirements, Methods and Models for early Electrified Drive Concept Development2025-01-0304To be published on 07/02/2025
Computer-aided synthesis and development tools are essential for discovering and optimizing innovative concepts. Evaluating different concepts and making informed decisions relies heavily on accurate assessments of drive system properties. Estimating these properties in the early stages of development is challenging due to the depth of modelling required. In addition, defined requirements play a critical role in drive system sizing. This paper presents a tool chain for the synthesis of new electrified drive concepts, with emphasis on requirements definition and modelling. The requirements definition method combines market analysis with a generalized calculation and estimation approach, providing a novel perspective. In addition, we introduce mass and cost modelling capabilities integrated into the tool chain. The mass model achieves high accuracy, with deviations of only 1.6% at the vehicle level and 6.1% at the component level. Finally, the paper examines the mass and cost
Sturm, Axel, Henze, Roman
Technical Paper
Acoustic Evaluation of Fiber-Based Materials for Engine Bay Applications2025-01-0115To be published on 05/05/2025
A newly formulated fiber-based material was developed to offer a cleaner, recyclable alternative to foam-based vehicle acoustic products. The fiber-based material was designed to be used in multiple vehicle acoustic applications, with different blends of the material available depending on the application. It performs well as an engine bay sound absorber due to its high heat tolerance and good absorption performance. A study was conducted to evaluate the sound absorption performance of this fiber-based material, specifically the engine bay blends, in comparison to that of current foam-based products. The results from this study show that the sound absorption performance of this new fiber-based material can match that of current foam-based materials while providing a recyclable product unlike the foam.
Krugh, Jack
Technical Paper
Cairene Car-Culture: How are Automobility and Social Behavior Linked to The Development of The Soundscape and Urban Fabric of Cairo.2025-01-0069To be published on 05/05/2025
Cairo’s soundscape has witnessed changes due to the ongoing urban structure developments that accommodate the number of vehicles passing through the city. The soundscape produced by this growing automobility is affected not only by vehicles but also by their owners' behavior. Cairenes use their cars as a communication tool and an extension of private space. By viewing the vehicle as a component of the soundscape as well as a space that filters it, this study examines the synergy between social behavior, automobility, urban structure, and their interdependent relationship on the soundscape of Cairo. The study responds to literature elaborating on acoustic ecology, car culture, urban structure, and social behavior. The methodology applied in this study follows practice-based phenomenological research while documenting and reflecting on car cultural practices in Cairo from an aural perspective. Grounded theory contextualizes the analysis of archived audio and video material, semi
Abd El Naby, Abla Mohamed
Technical Paper
Drilling Methods for Controlling Exit Burr Height in CRES Material Stacks2025-01-0169To be published on 05/02/2025
The Electroimpact Automatic Fan Cowl Riveter uses two novel drill processes to control exit burr height and achieve the required hole quality in CRES (Corrosion-Resistant Steel, also called stainless steel) material stacks. Both processes use piloted cutters on the OML side, and two different tools are used in a backside spindle on the IML side of the component. The first process uses a shallow-angle shave tool in the IML spindle to directly control the exit burr height after it is produced by the OML spindle and is called the “burr shave” technique. The second process uses a countersink tool in the IML spindle and produces an “intermediate countersink” after the pilot hole is drilled by the OML spindle, but before the final hole diameter is drilled. These drill processes were able to achieve the required hole quality in a challenging CRES material stack, which allows the machine to be qualified for one-up assembly of the component.
Schultz, Rich, Peterman, Randy, Luker, Zachary, Murakonda, Sai Krishna
Technical Paper
Material Adapted Method for the Repair of Curved Thermoplastic Composite Structures by Induction Welding of Patches2025-01-0165To be published on 05/02/2025
Thermoplastic fiber-reinforced polymer composites (TPCs) are gaining importance in aviation due to their high strength, stiffness, and recyclability. To maximize their potential, efficient repair methods are needed to maintain aircraft safety and structural integrity. This article introduces a novel repair technique for damaged TPC structures, involving the insertion of a repair patch with a susceptor material. The susceptor consists of a material with high electrical conductivity and magnetic permeability and therefore reacts stronger to the electromagnetic field than the composite, even if it is carbon fiber based. This means that the thermal energy is specifically concentrated in the repair area. The susceptor can be placed on the patch surface or in the welding zone. The process begins by identifying and preparing the damaged area, followed by precise scarfing. Care is taken to ensure that the surrounding material remains intact and that an exact stepped structure is created, which
Geiger, Markus, Glaap, Anton, Schiebel, Patrick, May, David
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
SAE TOMORROW TODAY BRIEFS - Scaling Software-Defined EV Fleets1351204/25/2025
When it comes to electrifying commercial vehicle fleets, one company offers a transformative modular platform that can drastically reduce the time to market. REE Automotive is a publicly traded company that designs and manufactures advanced software-defined vehicles (SDVs) that are fully electric, capable of autonomy, and compatible with existing fleet management software. The company recently began production on its first medium-duty truck for the US market and has since seen a 230% growth in reservations, indicating strong customer interest and positive feedback. To learn more, Roberto Baldwin, Sustainability Editor, SAE Sustainable Mobility Solutions, recently sat down with Daniel Barel, CEO, and Pete Dow, VP of Engineering, to discuss REE Automotive's revolutionary approach to scaling software-defined commercial EV fleets. For more information on the evolution of sustainability, head on over to sustainablecareers.sae.org. There, you can check out our podcast on the state of NEVI
Hineman, Marcie
Podcast
Airline Tow Tractor - Baggage/Cargo Factors for Design ConsiderationAIR1316C (Current)04/24/2025
This document outlines the functional and design requirements for baggage/cargo tow tractors used for airline services.
AGE-3 Aircraft Ground Support Equipment Committee
Information Report
Fluid, Aircraft Deicing/Anti-Icing, SAE Type IAMS1424T (Current)04/14/2025
This foundation specification (AMS1424T) and its associated category specifications (AMS1424/1 and AMS1424/2) cover a deicing/anti-icing material in the form of a fluid.
G-12ADF Aircraft Deicing Fluids
Material Specification
Air Conditioning Service Procedures for Off-Road Work Machines and Agricultural Tractors Using HFC-134a or HFO-1234yf RefrigerantJ3126_202504 (Historical)04/14/2025
This SAE Recommended Practice is intended to provide technicians with safe and efficient techniques and general equipment recommendations for servicing mobile air conditioning systems in off-road, self-propelled work machines as defined in SAE J1116 and tractors and machinery for agriculture and forestry as defined in ASABE standard ANSI/ASAE S390. Both refrigerants HFC-134a (R-134a) and HFO-1234yf (R-1234yf) are covered. Many service procedures are similar for both refrigerants, but recovery, recycling, charging, and electronic leak detection tools can be unique to each refrigerant.
HFTC6, Operator Accommodation
Recommended Practice
Detailed Specification for Aircraft Pressure Refueling NozzleAS5877C (Current)04/14/2025
This SAE Aerospace Standard (AS) prescribes requirements for the various types of nozzles that are used for the refueling and defueling of aircraft fitted with pressure fuel servicing systems. It is to be used as a replacement for MIL-N-5877 and MS29520 and for all commercial applications.
AE-5C Aviation Ground Fueling Systems Committee
Technical Standard
SAE TOMORROW TODAY UNPLUGGED - The Fragmentation of the Robotaxi Market1351004/10/2025
The robotaxi market is experiencing significant change, with the once-dominant Waymo now facing competition from new entrants like Nuro and Wayve who are licensing their autonomous driving technology -- a strategy that could reshape the industry. In addition, Tesla's Cybercab is aiming to launch a commercial service by the end of 2025 that allows owners to generate revenue through the Tesla network. Lyft and Uber are also adapting through the power of partnership, emphasizing the importance of fleet management in the operation and maintenance of robotaxis. In this Unplugged episode of SAE Tomorrow Today, host Grayson Brulte breaks it all down and discusses how the impact of a fragmented market will likely result in a convergence of personally owned AVs, traditional robotaxis, and niche players. Have your own thoughts on this topic? We'd love to hear from you! Share your comments, questions or ideas for future topics with Grayson on Twitter or send them to podcast@sae.org. Follow SAE on
Hineman, Marcie
Podcast
INSTALLING AND REMOVAL TOOLS, CONNECTOR ELECTRICAL CONTACT, TYPE I, CLASS 1, COMPOSITION CAS81969/17A (Current)04/02/2025
AE-8C2 Terminating Devices and Tooling Committee
Technical Standard
Do Aftermarket and Original Equipment Forward Collision Warning Systems Respond the Same to Vehicles and Pedestrians?2025-01-867704/01/2025
About 32% of registered vehicles in the U.S are equipped with automatic emergency braking or forward collision warning (FCW) systems [1]. Retrofitting vehicles with aftermarket devices can accelerate the adoption of FCW, but it is unclear if aftermarket systems perform similarly to original equipment manufacturer (OEM) systems. The performance of four low-cost, user-installable aftermarket windshield-mounted FCW systems was evaluated in various Insurance Institute for Highway Safety (IIHS) rear-end and pedestrian crash avoidance tests and compared with previously tested OEM systems. The presence and timing of FCWs were measured when vehicles approached a stationary passenger car at 20, 40, 50, 60, and 70 km/h, motorcycle and dry van trailer at 50, 60, and 70 km/h, adult pedestrian at 40 and 60 km/h, and child pedestrian crossing the road at 20 and 40 km/h. Equivalence testing was used to determine if FCW performance was similar for aftermarket and OEM systems. OEM systems provided a
Kidd, David, Floyd, Philip, Aylor, David
Technical Paper
Zero Circumferential Material Flow Line-Based Method for Reducing Stamping Simulation Cost2025-01-822404/01/2025
In sheet metal simulation, computation time is significantly influenced by the number of elements used to discretize the sheet blank, which covers the shape of forming tool geometry. Based on particle kinematics, motion of material point is modeled, and the concept of zero circumferential motion material line (ZML) is proposed. The slope ratio of material line (SRML) is proposed to quantify the circumferential deviation for determining the ZML. Based on the SRML, a method is developed to segment sheet blank and apply constraints. The method is demonstrated through forming simulation on a Hishida geometry. The proposed method, with its minimal to no circumferential motion along ZMLs, exhibits high level of accuracy retention while simultaneously impressively reducing computation time (up to 77%). This combination of efficiency and precision makes it a compelling approach for reducing simulation cost.
Sheng, ZiQiang, Asimba, Brian, Cabral, Kleber
Technical Paper
Research on Path Tracking Control of Electric Towbarless Aircraft Taxiing System under Crosswind Condition2025-01-828304/01/2025
The lateral dynamic and kinematic models of the electric towbarless towing vehicle (TLTV)–aircraft system, incorporating active front steering for the TLTV, are formulated to evaluate the impact of crosswind on the aircraft’s towing trajectory. This analysis considers scenarios with varying towing velocities and crosswind directions and intensities. To mitigate crosswind-induced disturbances affecting the aircraft’s motion, A high-speed and low-speed Model Predictive Control (MPC) strategy for the active front steering of a TLTV is proposed. This strategy is designed to optimize the TLTV’s steering performance under varying operational conditions, addressing the distinct dynamic characteristics of high-speed and low-speed towing scenarios. Simulation results demonstrate that the proposed control method achieves exceptional performance in both speed regulation and path tracking during towing operations.
Zhu, Hengjia, Bai, Zehao, Xu, Yitong, Zhang, Wei
Technical Paper
Research on Anti-Slip Traction Control for Aircraft Engine-off Towing System2025-01-829204/01/2025
When the aircraft towbarless towing vehicle (TLTV) drives on road surfaces that are wet, icy, oily, or covered with debris, as well as under conditions such as overloaded towing, uneven distribution of aircraft weight, sudden acceleration and sharp turns, brake system failures, or severe tire wear, it may slip due to a mismatch between traction force and ground adhesion. As a key piece of ground support equipment at airports, the anti-slip performance of TLTV is crucial for ensuring safe and efficient ground movement of aircraft. With continuous advancements in control technology, extensive research has been conducted on anti-slip control strategies for TLTV. This paper reviews relevant literature in the field of anti-slip control for TLTV in recent years, focusing on the current status of anti-slip control technology development, control strategies, and the application of co-simulation technology in anti-slip control. Based on co-simulation using Matlab and Adams software, this paper
Yao, Yanan, Xu, Yitong, Zhu, Hengjia
Technical Paper
Using CAN Electrical Signals for Cybersecurity and Harness Diagnostics2025-01-808004/01/2025
This paper describes a novel invention which is an Intrusion Detection System based on fingerprints of the CAN bus analogue features. Clusters of CAN message analogue signatures can be associated with each ECU on the network. During a learning mode of operation, fingerprints can be learnt with the prior knowledge of which CAN identifier should be transmitted by each ECU. During normal operation, if the fingerprint of analogue features of a particular CAN identifier does not match the one that was learnt then there is a strong possibility that this particular CAN identifier’s message is symptomatic of a problem. It could be that the message has been sent by either an intruder ECU or an existing ECU has been hacked to send the message. In this case an intruder can be defined as a device that has been added to the CAN bus OR a device that has been hacked/manipulated to send CAN messages that it was not designed to (i.e. could be originally transmitted by another device). It could also be
Quigley, Christopher, Charles, David
Technical Paper
Telematics-Based Managed EV Charging: A Pilot Case Study for Utility Bulk and Distribution Grid Services2025-01-812204/01/2025
Growth in the EV market is resulting in an unprecedented increase of electrical load from EV charging at the household level. This has led to concern about electric utilities’ ability to upgrade electrical distribution infrastructure at an affordable cost and sufficient speed to keep up with EV sales. Adoption of EVs in the California market has outpaced the national average and offers early insight for other regions of the United States. The Sacramento Municipal Utility District (SMUD) partnered with two grid-edge Distributed Energy Resource Management System (DERMS) providers, the OVGIP (recently incorporated as ChargeScape, a joint venture of Ford, BMW, Honda, and Nissan) and Optiwatt, to deliver a vehicle telematics-based active managed charging pilot. The pilot program, launched in Summer 2022 enrolled approximately 1,200 EVs over two years including Tesla, Ford, BMW, and GM vehicles. The goal of this pilot program was to evaluate the business case for managed charging to mitigate
Liddell, Chelsea, Schaefer, Walter, Dreffs, Kora, Moul, Jacob, Kay, Carol, Aswani, Deepak
Technical Paper
Matchit: A Domain-Adaptable Information Extraction and Categorization Tool for Enhanced Decision Making2025-01-810704/01/2025
This paper presents Matchit, a novel method for expediting issue investigation and generating actionable insights from textual data. Recognizing the challenges of extracting relevant information from large, unstructured datasets, we propose a domain-adaptable approach by integrating expert domain knowledge to guide Large Language models (LLMs) to automatically identify and categorize key information into distinct topics. This process offers two key functionalities: fully automatic topic extraction based solely on input data, providing a concise overview of the problem and potential solutions, and user-guided extraction, where domain experts can specify the type of information or pre-defined categories to target specific insights. This flexibility allows for both broad exploration and focused analysis of the data. Matchit's efficacy is demonstrated through its application in the automotive industry, where it successfully extracts repair diagnostics from diverse textual sources like
Wang, Lijun, Arora, Karunesh
Technical Paper
Enhancing Tire Predictive Maintenance with Next-Generation TPMS Sensors2025-01-875904/01/2025
This paper presents findings on the use of data from next-generation Tire Pressure Monitoring Systems (TPMS), for estimating key tire states such as leak rates, load, and location, which are crucial for tire-predictive maintenance applications. Next-generation TPMS sensors provide a cost-effective and energy-efficient solution suitable for large-scale deployments. Unlike traditional TPMS, which primarily monitor tire pressure, the next-generation TPMS used in this study includes an additional capability to measure the tire's centerline footprint length (FPL). This feature offers significant added value by providing comprehensive insights into tire wear, load, and auto-location. These enhanced functionalities enable more effective tire management and predictive maintenance. This study collected vehicle and tire data from a passenger car hatchback equipped with next-generation TPMS sensors mounted on the inner liner of the tire. The data was analyzed to propose vehicle-tire physics
Sharma, Sparsh, Son, Roman
Technical Paper
Options for Introducing SOVD in SDV Architectures2025-01-808104/01/2025
The trend for the future mobility concepts in the automotive industry is clearly moving towards autonomous driving and IoT applications in general. Today, the first vehicle manufacturers offer semi-autonomous driving up to SAE level 4. The technical capabilities and the legal requirements are under development. The introduction of data- and computation-intensive functions is changing vehicle architectures towards zonal architectures based on high-performance computers (HPC). Availability of data-connection to the backend and the above explained topics have a major impact on how to test and update such ‘software-defined’ vehicles and entire fleets. Vehicle diagnostics will become a key element for onboard test and update operations running on HPCs, as well as for providing vehicle data to the offboard backend infrastructure via Wi-Fi and 5G at the right time. The standard for Service Oriented Vehicle Diagnostics (SOVD) supports this development. It describes a programming interface for
Mayer, Julian, Bschor, Stefan, Fieth, Oliver
Technical Paper
Next-Gen Italian Urban Mobility: Emissions LCA and TCO Prospective for Innovative Transportation Solutions2025-01-859304/01/2025
Reducing vehicle numbers and enhancing public transport can significantly cut emissions in the transport sector. Hydrogen-fueled and battery electric buses show the potential for decarbonization, but a Life Cycle Assessment (LCA) is essential to evaluate carbon emissions from energy production and manufacturing. In addition, even associated pollutant emissions, together with components’ wear, must be taken into account to evaluate the overall environmental impact. Total Cost of Ownership (TCO) analysis complements this by assessing long-term expenses, enabling stakeholders to balance environmental and economic considerations. This study examines carbon and pollutant emissions alongside TCO for innovative urban mobility powertrains (compared with diesel), focusing on Italian current and future hydrogen and electricity mix scenarios, even considering 100 % green hydrogen (100GH), the goal being to support sustainable decision-making and to promote eco-friendly transport solutions. The
Brancaleoni, Pier Paolo, Damiani Ferretti, Andrea Nicolò, Corti, Enrico, Ravaglioli, Vittorio, Moro, Davide
Technical Paper
Decoding User Experience: A Study of Public EV Charging Stations Based on Amap Comments2025-01-811504/01/2025
The rapid expansion of the electric vehicle (EV) market has intensified the need for robust charging infrastructure. The quality of their experiences at public charging stations has become crucial to sustaining this transition. Key factors such as station accessibility, charging speed, and pricing transparency significantly affect user satisfaction. In Guangzhou, a China's major metropolitan city with an EV penetration rate exceeding 50%, this city offers an ideal context to assess the alignment between expanding EV infrastructure and user needs. This study examines user satisfaction with EV public charging stations in Guangzhou using a dataset of over 2,000 user comments from Amap. The comments are first processed using the Jieba segmentation library, with sentiment analysis conducted through the Natural Language Processing tool SnowNLP, categorizing comments by sentiment (419 positive, 156 neutral, and 1,690 negative). Term Frequency-Inverse Document Frequency(TF-IDF) is then applied
Guo, Haifeng, Ou, Shiqi (Shawn), Jing, Hao, Qi, Hao, Shi, Lanxin
Technical Paper
Designing Software for SAE J1939 ECUs to Improve Cybersecurity2025-01-808204/01/2025
SAE J1939 is a CAN-based standard used for connecting various ECUs together within a vehicle. There are also some related protocols sharing many of the features of SAE J1939 across other industries including ISO11783, RVC and NMEA 2000. The standard has enabled the easy integration of electronic devices into a vehicle. However, as with all CAN-based protocols, several vulnerabilities to cyberattacks have been identified and are discussed in this paper. Many are at the CAN-level, whilst others are in common with those protocols from the SAE J1939 family of protocols. This paper reviews the known vulnerabilities that have been identified with the SAE J1939 protocol at CAN and J1939-levels, along with proposed mitigation strategies that can be implemented in software. At the CAN-level, the weaknesses include ways to spoof the network by exploiting parts of the protocol. Denial of Service is also possible at the CAN-level. At the SAE J1939-level, weaknesses include Denial of Service type
Quigley, Christopher
Technical Paper
Machine Learning-Based Digital Twin for Optimizing Automotive Components2025-01-820604/01/2025
This paper presents a Digital Twin approach based on Machine Learning (ML), aimed at creating software-based sensors to reduce the auxiliary devices of the vehicle and enabling predictive maintenance, thus reducing carbon footprint. The solution is applied to the electric Lubrication Oil Pump (eLOP), a crucial component within a vehicle's powertrain system. The proposed eLOP Digital Twin integrates ML-based sensors to estimate critical parameters such as temperature, pressure and flow rate, reducing the reliance on physical sensors and associated hardware. This approach minimizes manufacturing complexity and cost, enhancing energy efficiency during both production and operation. Furthermore, the Digital Twin facilitates predictive maintenance by continuously monitoring the component's performance, enabling early detection of potential failures and optimizing maintenance schedules. This leads to lower energy consumption and reduced emissions throughout the component's lifecycle. The
Khan, Jalal, D'Alessandro, Stefano, Tramaglia, Federico, Fauda, Alessandro
Technical Paper
Modelling Spray Washing with Lagrangian Differencing Dynamics2025-01-863504/01/2025
Spray washing is commonly used in car manufacturing to clean and prepare surfaces for subsequent processes like coating and painting. It uses high-pressure spray to deliver cleaning solutions or water onto vehicle surfaces to remove dirt, oils, metal shavings, and contaminants. For optimal washing quality, it is important to have proper nozzle arrangements, spray configuration, and vehicle positioning. Numerical simulations can be used to minimize the trial-and-error process and improve the quality. Spray washing involves strong discontinuities, fragmentation, violent free-surface changes, and complex multiphase flow, which are difficult to simulate using conventional grid-based methods. Lagrangian differencing dynamics (LDD) is a novel numerical method which has the features of being Lagrangian, meshless, and second-order accurate. It employs a meshless finite difference approximation scheme over scattered points and solves the incompressible Navier-Stokes equations in an implicit way
Panov, Dmitrii Olegovich, Zhu, Huaxiang, Basic, Josip, Zhang, Lingran, Champaneriya, Vrajesh, Saghatchi, Roozbeh, Peng, Chong, Kotian, Akhilesh, Ando, Yuya
Technical Paper
Concept of On-Board Diagnostics System of Vehicle Electric Drive2025-01-809504/01/2025
The problem of monitoring the parametric failures of a traction electric drive unit consisting of an inverter, a traction machine and a gearbox when interacting with a battery management system has been solved. The strategy for solving the problem is considered for an electric drive with three-phase synchronous and induction machines. The drive power elements perform electromechanical energy conversion with additional losses. The losses are caused by deviations of the element parameters from the nominal values during operation. Monitoring gradual failures by additional losses is adopted as a key concept of on-board diagnostics. Deviation monitoring places increased demands on the information support and accuracy of mathematical models of power elements. We take into account that the first harmonics of currents and voltages of a three-phase circuit are the dominant energy source, higher harmonics of PWM appear as harmonic losses, and mechanical losses in the rotor and gearbox can be
Smolin, Victor, Gladyshev, Sergey, Topolskaya, Irina
Technical Paper
Kalmar launches 3rd-gen electric terminal tractor25TOFHP04_1004/01/2025
Electric vehicle (EV) growth may be stagnant in certain market sectors amid pushback on EV mandates along with lingering infrastructure and TCO concerns, but in terminal tractor operations electrification is growing in demand. As part of its initial Run on Less - Electric demonstration, the North American Council for Freight Efficiency (NACFE) concluded that terminal tractors are “one of the best, if not the best, paths for heavy-duty tractor fleets to learn about and implement a BEV in a fleet operation.” Fleets operating in ports, intermodal yards and other logistics hubs have a new option from which to choose now that Kalmar officially began sales of its Ottawa T2 EV electric terminal tractor. The order book opened at the Technology & Maintenance Council's (TMC) 2025 Transportation Technology Exhibition in Nashville, Tennessee, in March. Kalmar states that select customers have already placed preorders. Initial deliveries will begin in Q2 2025.
Gehm, Ryan
Magazine Article
J1939 Digital AnnexJ1939DA_202503 (Current)03/31/2025
This document is intended to supplement the J1939 documents by offering the J1939 information in a form that can be sorted and searched for easier use.
Truck and Bus Control and Communications Network Committee
Supplement
Water Spray and High Humidity Endurance Test Methods for AMS1424 and AMS1428 Aircraft Deicing/Anti-Icing FluidsAS5901E (Current)03/25/2025
This document establishes the minimum requirements for an environmental test chamber and test procedures to carry out anti-icing performance tests according to the current materials specification for aircraft deicing/anti-icing fluids. The primary purpose for such a test method is to determine the anti-icing performance under controlled laboratory conditions of AMS1424 Type I and AMS1428 Type II, III, and IV fluids.
G-12ADF Aircraft Deicing Fluids
Technical Standard
Advancing Oil Maintenance Practices: Insights from Viscosity Analysis2025-01-501903/21/2025
There is a lack of data to support the efficacy of traditional mileage and time-based criteria for oil changes in vehicles. In this study, used-oil samples from 63 vehicles were collected and analyzed. Besides dynamic viscosity, viscosity index and activation energy were evaluated as measures of thermal stability of viscosity. The results revealed that mileage and time of use are not significantly correlated with (p > 0.05) and are thus poor indicators of oil viscosity and viscosity thermal stability measures. These findings highlight the limitations of current criteria and underscore the need for new sensing and evaluation methods to reduce costs, waste, and environmental impact while ensuring vehicle performance.
Salvi, Nilesh, Tan, Jinglu
Technical Paper
The Logistic Lasso and Ridge Regression Algorithm-Based Airline Passenger Satisfaction Prediction Model2025-01-716803/19/2025
Airline passenger satisfaction is important for airline operation service quality management. When airline companies carry out advertisement campaigns or plan a marketing strategy, the resources and budgets are not unlimited. Thus, an airline can only focus on improving a few factors that drive passenger satisfaction. To understand the key satisfies for the young and the old adults, respectively, we leverage five airline passenger satisfaction methods to identify the key factors that explain the airline service satisfaction of different passengers. In particular, we investigate and compare the ridge and the Lasso regularization in terms of the resulting model’s sparsity and computational efficiency. The top three important factors that influence the old’s satisfaction are departure and arrival time convenience, legroom service, and baggage handling. Our findings indicate that the young people place a higher value on entertainment, while the old adults place a higher value on usefulness
Ma, Jie, Hu, Song, Wang, Haipeng
Technical Paper
Traffic Event Extraction and Geographization from Natural Language Web Text2025-01-721303/19/2025
Real-time traffic event information is essential for various applications, including travel service improvement, vehicle map updating, and road management decision optimization. With the rapid advancement of Internet, text published from network platforms has become a crucial data source for urban road traffic events due to its strong real-time performance and wide space-time coverage and low acquisition cost. Due to the complexity of massive, multi-source web text and the diversity of spatial scenes in traffic events, current methods are insufficient for accurately and comprehensively extracting and geographizing traffic events in a multi-dimensional, fine-grained manner, resulting in this information cannot be fully and efficiently utilized. Therefore, in this study, we proposed a “data preparation - event extraction - event geographization” framework focused on traffic events, integrating geospatial information to achieve efficient text extraction and spatial representation. First
Hu, Chenyu, Wu, Hangbin, Wei, Chaoxu, Chen, Qianqian, Yue, Han, Huang, Wei, Liu, Chun, Fu, Ting, Wang, Junhua
Technical Paper
Digital Annex of Medium/Heavy-Duty E/E Systems Diagnosis NomenclatureJ2403DA_202503 (Current)03/10/2025
This document is intended to supplement SAE J2403 by providing the content of Table 1, Table 2, and Table 3 from SAE J2403 in a form that can be sorted and searched for easier use. It is NOT intended as a substitute for the actual document, and any discrepancies between this Digital Annex and the published SAE J2403 document must be resolved in favor of the published document. This document provides the content of Table 1 and Table 2 published in SAE J2403 into the single table in the 'Term' tab, while the 'Recommended Term Definitions' tab provides the content of Table 3 in SAE J2403 and the 'Glossary' tab provides the content of Table 4 in SAE J2403.
Truck and Bus Control and Communications Network Committee
Supplement
Isolation and Corrosion Protection of Dissimilar Materials, Carbon Composite Structure RepairARP4118C (Current)03/05/2025
This SAE Aerospace Recommended Practice (ARP) provides methods and guidelines for isolating dissimilar repair patch materials from carbon fiber reinforced plastic (herein also referred to as carbon composite) structure during a repair operation.
AMS G9 Aerospace Sealing Committee
Recommended Practice
Design and Safety Criteria for Passenger Boarding StairwaysAIR6133A (Current)03/05/2025
AGE-3 Aircraft Ground Support Equipment Committee
Information Report
Synthetic On-Board Diagnostics Data Generation and Evaluation for Vehicle Diagnostic Testing2025-01-501003/04/2025
The generation of data plays a vital role in machine learning (ML) techniques by providing the foundation for training and improvement of forecast models. As one application area for these models, in-vehicle systems, like vehicle diagnostics, have the potential to enhance the reliability and durability of vehicles by utilizing ML models in the testing phases. However, acquiring a high volume of quality onboard diagnostics (OBD) data is time-consuming and poses challenges like the risk of exposing sensitive information. To address this issue, synthetic data generation offers a promising alternative that is already in use in other domains. Thereby, synthetic data allows the exploitation of knowledge found in original data, ensuring the privacy of sensitive data, with less time costs of data acquisition. The application of such synthetically generated data could be found in predictive maintenance, predictive diagnostics, anomaly detection, and others. For this purpose, the research
Vučinić, Veljko, Hantschel, Frank, Kotschenreuther, Thomas
Technical Paper
Vehicle Application LayerJ1939/71_202502 (Current)02/25/2025
The SAE J1939 communications network is developed for use in heavy-duty environments and is suitable for horizontally integrated vehicle industries. The SAE J1939 communications network is applicable for light-duty, medium-duty, and heavy-duty vehicles used on-road or off-road, and for appropriate stationary applications which use vehicle-derived components (e.g., generator sets). Vehicles of interest include, but are not limited to, on-highway and off-highway trucks and their trailers, construction equipment, and agricultural equipment and implements. SAE J1939-71 is the SAE J1939 reference document describing SAE J1939 parameter (SP) and message (PG) definitions, SLOT (standard data encoding) definitions, conventions and notations used to specify the parameter (SP) placement in PG data, conventions for text data parameters, and conventions for PG transmission rates. This document previously contained the majority of the SAE J1939 OSI application layer data parameters and messages for
Truck and Bus Control and Communications Network Committee
Technical Standard
R-1234yf Service Hose, Fittings, and Couplers for Mobile Refrigerant Systems Service EquipmentJ2888_202502 (Current)02/25/2025
This SAE Standard covers fittings, couplers, and hoses intended for connecting service hoses from mobile air-conditioning systems to service equipment such as charging, recovery, and recycling equipment (see Figure 1). This specification covers service hose fittings and couplers for MAC service equipment service hoses, per SAE J2843 and SAE J2851, from mobile air-conditioning systems to service equipment such as manifold gauges, vacuum pumps, and air-conditioning charging, recovery, and recycling equipment.
Interior Climate Control Service Committee
Recommended Practice
Endurance Time Test Procedures for SAE Type I Aircraft Deicing/Anti-Icing FluidsARP5945B (Current)02/24/2025
The purpose of this ARP is to provide the sample selection criteria and endurance time test procedures for SAE Type I aircraft deicing/anti-icing fluids required for the generation of endurance time data of acceptable quality for review by the SAE G-12 Holdover Time Committee. A significant body of previous research and testing has indicated that all Type I fluids formulated with conventional glycols, as defined in 3.1.1 of AMS1424, perform in a similar manner from an endurance time perspective. This applies to Type I deicing/anti-icing fluids formulated with propylene glycol, ethylene glycol, and diethylene glycol only. As a result, Type I deicing/anti-icing fluids containing these glycol bases no longer require testing for endurance times. The methods described in this ARP shall be employed, however, if endurance time testing of a conventional glycol-based Type I deicing/anti-icing fluid is desired or requested by a fluid manufacturer, operator, or other organization. Fluids
G-12HOT Holdover Time Committee
Recommended Practice
Tunnel Lining Crack Intelligent Recognition Based on YOLOv11 Algorithm2025-01-713702/21/2025
Tunnel linings are an important safeguard for the integrity and stability of tunnels. However, cracks in the tunnel lining may have extremely unfavourable consequences. With the acceleration of urbanisation and the increasing construction of tunnels, the problem of cracks in the concrete lining is becoming more and more prominent. These cracks not only seriously affect the stability of the structure, but also pose a serious threat to the safety of tunnel operation. If left unchecked, the cracks may expand further and cause various safety hazards, such as water leakage and falling blocks. This in turn will undermine the normal function of the tunnel and endanger the lives of tunnel users. It has been proved that the traditional manual method of detecting cracks in tunnels has problems such as low accuracy and low efficiency. In order to solve this problem, it is very necessary for this study to pioneer an intelligent method for identifying tunnel lining cracks using the YOLOv11
Zhang, Yalin, Niu, Pei, Guo, Feng, Yan, Wei, Liu, Jian, Kou, Lei
Technical Paper
Classification of Pavement Distress Images Using Fusion Convolutional Neural Network of Dual Branch2025-01-713102/21/2025
In recent years, the issue of highway maintenance has become increasingly prominent. How to precisely detect and classify fine cracks and various types of pavement defects on highways through technical means is an essential foundation for achieving intelligent road maintenance. This paper first constructs the DenseNet201-PDC and MobileNetV2-PDC sub-classification networks that incorporate the three-channel attention judgment mechanism MCA. Secondly, based on the principle of parallel connection, a brand-new dual-branch fusion convolutional neural network DBF-PDC capable of classifying pavement defects in highway scenarios is proposed. Finally, this paper builds the Pavement Distress Datasets of Southeast University and conducts relevant ablation experiments. The experimental results demonstrate that both the attention mechanism module and the feature fusion strategy can significantly enhance the network's ability to classify pavement defects in highway scenarios. The average
Zhang, Ziyi, Zhao, Chihang, Shao, Yongjun, Wang, Junjun
Technical Paper
A Real-Time Multiplayer SUMO-Unity Co-Simulation Platform for Vehicle-Aircraft Coordinated Operation2025-01-719702/21/2025
As the demands for air travel and air cargo continue to grow, airport surface operations are becoming increasingly congested, elevating the operational risks for all entities. Conventional measurement methods in airport traffic scenarios are limited by high temporal and spatial costs, uncontrollable variables, and their inabilities to account for low-probability events. Moreover, current simulation software for airport operations exhibits weak simulation capabilities and poor interactivity. To address these issues, this study developed a virtual reality traffic simulation platform for airport surface operations. The platform integrated 3D modeling technologies, including Blender and Unity, with the Photon Fusion multiplayer platform and Simulation of Urban Mobility (SUMO) traffic simulation software. By incorporating Logitech external devices, the platform enabled real-time human-driven simulations, multiplayer online interactions, and validation of airport traffic flow models. To
Zhang, Yuheng, Han, Zhongyi, Zhang, Yuhan, Ye, Zhirui
Technical Paper
Modeling Internal Node Impedance in High-Speed Rail Passenger Hubs Based on Queuing Theory2025-01-717202/21/2025
High-speed railway (HSR) hubs play a pivotal role in the integrated transport system, efficiently connecting various modes of transport and facilitating transport integration. Characterized by their large scale, complex functional spatial layouts, and diverse interchange types, these hubs see a growing proportion of passenger traffic annually. Thus, studying the interchange impedance in high-speed railway passenger transport hubs is crucial for enhancing interchange efficiency and service quality. However, current research lacks a quantitatively comparable impedance model for high-speed railway hubs, particularly under peak passenger flow conditions. This paper addresses this gap by examining the internal node impedance at Nanjing South Railway Station, focusing on the entry gate turnstile node and security check node. It begins by analyzing passenger passing behavior at these nodes and then constructs a integrated queuing model for inbound gates and security checks, considering the
Zhang, Zhenyu, Wang, Jian
Technical Paper
Mobile Laser Scanning for Tunnel Inspection2025-01-715402/21/2025
Monitoring the safety and structural condition of tunnels is crucial for maintaining critical infrastructure. Traditional inspection methods are inefficient, labor-intensive, and pose safety risks. With its non-contact, high-precision, and high-efficiency features, mobile laser scanning technology has emerged as a vital tool for tunnel monitoring. This paper presents a mobile laser scanning system for tunnel measurement and examines techniques for calculating geometric parameters and processing high-resolution imaging data. Empirical evidence demonstrates that mobile laser scanning offers a reliable solution for evaluating and maintaining tunnel safety.
Lianbi, Yao, Zhang, Kaikun, Duan, Wei, Sun, Haili
Technical Paper
Research on Triple-Frequency Dual-Ionosphere-Free Combination PPP Based on PPP-B2b Service2025-01-715702/21/2025
The recent public release of the PPP-B2b service, along with advancements in multi-frequency and multi-GNSS systems, has opened up significant new opportunities for the development of Precise Point Positioning (PPP) technology. Utilizing the precise orbit and clock corrections provided by PPP-B2b and the increasing availability of multi-frequency signals, this paper introduces a novel tri-frequency, dual ionosphere-free PPP model based on PPP-B2b services. The model is designed with twelve unique tri-frequency combinations, tailored to various frequency choices, combination methodologies, and single/dual GNSS systems. Results from static positioning experiments indicate that the BDS-only tri-frequency dual ionosphere-free model offers substantial improvements over traditional models. Specifically, it achieves approximately a 25% increase in vertical accuracy and reduces convergence time by around 30% when compared to the BDS-only tri-frequency undifferenced uncombined model. This
Xu, Dawei, Gao, Chengfa, Xu, Zhenhao, Zhan, Kaidi, Guo, Songlin
Technical Paper
Intelligent Pavement Maintenance Optimization Technique for Automatic Driving2025-01-715302/21/2025
Compared to manual driving, autonomous driving is more prone to the rapid development and deterioration of pavement distress due to the concentration of driving paths. Therefore, a reasonable and efficient maintenance strategy is required. To address the challenges posed by the numerous constraints and objectives in the maintenance strategy generation process, this paper proposes a multi-objective optimization-based method for generating pavement maintenance strategies. The approach leverages advanced pavement distress detection technologies to establish an initial maintenance program, incorporating a range of constraints and maintenance objectives, such as cost-efficiency, performance longevity, and environmental impact. The method applies a genetic algorithm (GA) to iteratively refine and optimize the maintenance strategy, ensuring that the solutions align with both immediate and long-term performance goals for autonomous vehicle operations. A case study utilizing real-world road
Yang, Liwenyun, Li, Wei, Chen, Leilei
Technical Paper
Maintenance Scheduling Optimization of Urban Non-intrusive Road Intelligent Transportation System Equipment under the Autonomous Driving Environment2025-01-714802/21/2025
The increasing traveling demands are putting higher pressure on urban networks, where the efficient driving modes highly depend on various non-intrusive ITS equipment for interaction, which asks for higher maintenance scheduling plans minimizing network loss. Current studies have researched methodologies with the aspects of deterministic methods and metaheuristic algorithms under different scenarios, but lack the simulation considering maintenance work type, urban traffic characteristics as well as the ITS equipment. This study aims to optimize the maintenance scheduling plan of urban ITS systems by using the genetic algorithm (GA) and Dijkstra algorithm, as well as other judgmental algorithms to minimize traffic delays caused by maintenance activities, and presents a novel method to assess economic losses. A mixed integer programming model is established simulating the real urban network while considering multiple constraints, including the route selection principle, network updating
Pei, Haoyi, Ji, Yanjie, Chen, Ziang
Technical Paper
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