Browse Topic: Buses

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26M-00552026-01-0603To be published on 04/07/2026
Since air drag is proportional to the square of the speed, it is expected that reducing air drag will significantly improve fuel efficiency for long-distance trucks and buses, which are often driven at high speeds. Therefore, the purpose of this study is to propose a conceptual shape that will dramatically improve the aerodynamic performance of heavy-duty vehicles, assuming that restrictions on overall length will be relaxed in the future. Using NSGA-II, a genetic algorithm, the overall vehicle shape was optimized with the objective functions CD and CL values and design variables as parameters in a total of 13 locations. Among the Pareto solutions, CD = 0.08 was obtained when the CD value was the lowest. Since the CL value remains low with this shape, it can be seen that driving stability does not deteriorate. Among the design variables in optimization, it was confirmed that the corner radius of the vehicle side was particularly effective in reducing the CD value. In addition, when
Kawano, Daisuke
Operational Feasibility of Battery Swapping in U.S. Transit: A Case Study of King County Metro2026-01-0402To be published on 04/07/2026
Battery swapping technology has emerged as a promising alternative to conventional plug-in charging for electric bus fleets, offering rapid turnaround times and improved vehicle availability. This paper investigates whether battery swapping can be integrated into U.S. public transit bus operations without disrupting existing timetables. A Seattle based public transit agency- King County Metro is taken as a case study in this paper. Using General Transit Feed Specification data from King County Metro, a MATLAB model was built that reconstructs blocks and layovers, extracts dwell-time opportunities, and performs block distance and block time analyses to understand operational rhythms. A mathematical energy model was developed that maps route mileage, efficiency, and layover availability to swap decisions, using a look-ahead rule that defers exchanges whenever the next feasible layover can still be reached while respecting a minimum state-of-charge. The workflow estimates how many swaps
Vadlapatla, Taraka Rishi, Jankord, Gregory, D'Arpino, Matilde
From Propane to Pi: Affordable AI-Driven Solutions for Sustainable Bus Heating.2026-01-0164To be published on 04/07/2026
The design of an affordably luxurious school bus means improving passenger comfort while greatly decreasing energy usage and emissions. The key consideration is to replace traditional propane heating with an electric heated-seat system and supported by green electricity/energy efficient smart power management. The system is designed from a 24V/48V battery system; to a Smart Energy Cube - a portable dock in power module requiring solar, battery and grid connection. Seat heating is only applied to seats that are occupied. The on-board image processing models (YOLOv5/YOLOv8, OpenCV, TensorFlow Lite) are run on affordable/portable microcomputers capable of detecting the number of occupied and available seats e.g. Raspberry Pi. There is one bottle neck when using the Raspberry Pi in the experiments to validate concept, when using low/medium power frame rates of ~ 1 fps for Raspberry Pi 3; to 7-8 fps with a Raspberry Pi 5. As a baseline, there is still potential for improvement and
Chikkala, Daney Bhargav, Zadeh, Mehrdad, TAN, Teik-Khoon, Ponnam, Jitin, BATTE, JAI RATHAN
Protection of Megawatt-Scale DC Charging Infrastructure for Heavy Duty Vehicles: A Review of Current Technologies and Future Roadmap2026-01-0400To be published on 04/07/2026
Abstract Direct Current (DC) fast charging enables the direct delivery of megawatt (MW) scale power to the large battery systems of heavy-duty electric vehicles (EVs), such as trucks, buses, and construction machinery. This contrasts with Alternating Current (AC) charging, which is constrained by the limited capacity of onboard chargers. The feasibility of ultra-fast DC charging has been driven by advancements in semiconductor technology offering higher voltage and current handling capabilities as well as improvements in battery energy density. Ongoing research indicates continued growth in both semiconductor power handling and battery storage capacity, further strengthening the case for ultra-fast DC charging. Key benefits include significantly higher charging efficiency, drastically reduced charging times, and lower driver fatigue. However, unlike AC systems, DC charging infrastructure presents unique protection challenges. These challenges arise from the rapid rise of DC fault
Rahman, Md Rakib-Ur, Dobrzynski, Daniel
Physical Adversarial Infrastructure Attacks on Vision-Language Models for Autonomous Driving2026-01-0170To be published on 04/07/2026
Vision-language models (VLMs) offer a promising end-to-end approach for autonomous driving, but their robustness to physical adversarial attacks remains an unaddressed gap for safety-critical deployment. This paper introduces a systematic framework for evaluating these attacks using the Dolphins VLM and CARLA simulator. We employ Natural Evolution Strategies (NES), a black-box optimization method, to generate adversarial patches without internal model access. Our approach uses semantic similarity loss and Expectation over Transformation (EoT) to ensure physical realizability under varying viewing conditions. Patches are strategically placed on realistic advertising infrastructure (bus shelter panels and highway billboards), reflecting a plausible threat model. We establish two complementary scenarios: crosswalk pedestrian detection suppression and highway steering manipulation. Our evaluation reveals critical vulnerabilities. Adversarial patches achieved a 76.0% overall attack success
Fernandez, David, MohajerAnsari, Pedram, Salarpour, Amir, Pese, Mert D.
HaloBus: Edge Computing‑Enabled Real‑Time Boarding and Exit Detection for Enhanced Transportation Safety Using Lightweight AI2026-01-0555To be published on 04/07/2026
This paper proposes HaloBus, an innovative, edge‑computing solution designed to mitigate this risk by detecting student boarding and exiting in real time using lightweight AI based methods. A persistent challenge in elementary school transportation is the issue of missing students after they exit their buses, which disproportionately impacts low-income households. Current safety systems are forced upon the individual households with their own methods. Common methods include applications on a personal device or a small tracker. However, not everyone can afford these options, and every parent deserves to feel like their child is safe. That is why HaloBus was invented. The system employs YOLOv5u—an Ultralytics‑enhanced, anchor‑free, split‑head architecture that offers a superior accuracy–speed tradeoff. By providing real-time, on-device alerts, HaloBus enables immediate intervention to prevent a student from being left behind, thereby shifting the focus from reactive post-incident
Getz, Grayson, Zadeh, Mehrdad, TAN, Teik-Khoon
ProGuard: A Real-time Preemptive Artificial Intelligence-Based Anti-Pinch System for Bus Entryways on Low-Power Edge Devices2026-01-0100To be published on 04/07/2026
This paper proposes ProGuard, a novel approach to preemptive pinch detection systems for buses. ProGuard utilizes state-of-the-art AI object detection algorithms to identify potential pinching events in bus entryways before pinching occurs. Modern conventional anti-pinch systems, such as pressure sensors or hall effect sensors, often rely on mechanical contact before triggering. While these systems are established safety mechanisms, they are reactive and therefore require some level of pinching before triggering. This reactive approach presents numerous safety concerns for passengers, especially when considering children on school buses. Existing preemptive detection methods, such as infrared or ultrasonic sensors, solve the problems presented by these reactive detection systems. However, these systems either lack the range or environmental resilience needed for reliable operation in buses. The critical nature of anti-pinch systems requires a robust and reliable solution that can adapt
Bradley, Hudson, Zadeh, Mehrdad, TAN, Teik-Khoon
Common Mode Voltage Reduction in Quasi-Z Source Inverter for Electric Vehicle Applications Using MBPWM Technique2026-28-0102To be published on 02/12/2026
Unlike traditional voltage source or current source inverters, ZSI/qZSI can boost and invert DC power in a single stage, making them attractive for applications like EVs where battery voltage may vary. Common mode Voltage (CMV) is the voltage between the neutral point of the motor and ground. High CMV in motor drive systems can cause: Higher leakage currents, Electromagnetic interference (EMI), Insulation stress, bearing currents, leading to premature motor failure. Reducing CMV is essential for reliable and safe EV operation. Pulse-width modulation (PWM) is used to control the QZSI output voltage. The QZSI offers several advantages over traditional inverters, including improved efficiency, reduced cost, and increased reliability. The proposed system is designed to reduce the CMV through a combination of passive LC filtering and shoot-through (ST) modulation techniques. The LC filter is designed to attenuate high-frequency components of the CMV while the ST modulation is used to
N, Kalaiarasi, R, Rajarajeswari, D, Anitha
Multiphysics Analysis of Heat Sink Designs for Efficient Thermal Performance in Power Electronics Systems2026-26-04461/16/2026
The thermal management capability of power electronic (PE) systems has a critical impact on the performance and efficiency of electric, fuel cell, or hybrid vehicles. Bus bars, high resistance sensor devices, semiconductor switches, power capacitors are the primary components, which make a major contribution in total heat generation in electrical drive unit. As PE packaging sizes are projected to become smaller, the challenge of managing increased heat dissipation becomes more critical. This paper numerically compares six different cooling strategies to determine the best possible thermal management scenario. A coupled physics co-simulation framework is used to analyze a 35W motor inverter integrated with water cooled heat sink. A multi-physics finite element model, integrating fluid, electrical, and thermal fields, is employed to analyze heat generation within the PE system and the associated cooling mechanisms. The power losses from the inverter system are dynamically computed in 1-D
Singh, Praveen Kumar, Natarajan, Nesamani, Murali, Sariki
Auto Braking System for Preventing Commercial Vehicle Overloading2026-26-00321/16/2026
Overloading in vehicles, particularly trucks and city buses, poses a critical challenge in India, contributing to increased traffic accidents, economic losses, and infrastructural damage. This issue stems from excessive loads that compromise vehicle stability, reduce braking efficiency, accelerate tire wear, and heighten the risk of catastrophic failures. To address this, we propose an intelligent overloading control and warning system that integrates load-sensing technology with real-time corrective measures. The system employs precision load sensors (e.g., air below deflection monitoring via pressure sensors) to measure vehicle weight dynamically. When the load exceeds predefined thresholds, the system triggers a multi-stage response: 1 Visual/Audio Warning – Alerts the driver to take corrective action. 2 Braking Intervention – If ignored, the braking applied, immobilizing the vehicle until the load is reduced. Experimental validation involved ten iterative tests to map deflection-to
Raj, Amritesh, Pujari, Sachin, Londhe, Mahesh, Shirke, Sumeet, Shinde, Akshay
Optimisation-Driven Framework for Heterogeneous Battery-Pack Mixing in Fleet Applications2026-26-02091/16/2026
Fleet owners often encounter significant logistical and financial problems when dealing with battery packs of different ages and conditions. The standard industry practice is to replace old batteries with identical new ones. This process is inefficient because it costs a lot, creates too much inventory, and eliminates battery packs that are still useful too soon. The problem worsens when manufacturers stop making older battery models, which can force a vehicle to retire early. This paper puts forward a framework for mixing different types of battery packs to deliver the performance needed for a vehicle’s mission. We show how this works in three everyday service situations: 1) Repair, when a single damaged pack needs replacing; 2) Life Extension, where aged packs are combined with newer ones to meet mission range; and 3) Performance Restoration, which uses next-gen packs when the original parts are obsolete. The study shows that a vehicle can complete its required missions by
Nair, Sandeep R., Ravichandran, Balu Prashanth, Hallberg, Linus
Quantifying the Energy Consumption of HVAC Operation and Its Impact on the Range of Electric Buses Across Diverse Climatic Conditions2026-26-02041/16/2026
Electric buses (e-buses) are essential to sustainable public transport, but their real-world efficiency and range are heavily affected by auxiliary systems, particularly the Heating, Ventilation, and Air Conditioning (HVAC) system. This study investigates how ambient temperature variations and HVAC loads influence energy consumption, range, and efficiency in e-buses operating under diverse climatic conditions. The methodology combines field data collection from urban e-buses across seasons—including extreme summer and winter—with controlled laboratory testing. Field measurements included ambient temperature, HVAC demand, vehicle speed, state of charge (SOC) variation, and energy consumption. These inputs were used to develop real-world duty cycles, replicating actual thermal loads, passenger profiles, idling periods, and driving patterns. In the laboratory, these cycles were simulated using a chassis dynamometer and environmental chamber, with HVAC systems tested at controlled ambient
Vishe, Prashant, Dalela, Saurabh, Saraswat, Shubham, Joshi, Madhusudan
Dimensional Management in Automotive Vehicle Design & Development for Perceived Quality (PQ) Improvement in Buses2026-26-04471/16/2026
Perceived quality (PQ) is one of the most important factors in engineering signoff as well as customer delight and product improvement (feel, look & touch). The PQ is something related to feel of product in terms of gap, flushness, fitment and appearance as per the costumer perceptions and expectations. Validation of design and engineering quality with respect to perceived quality is required for overall product appearance in the eyes of prospective customers. This is equally applicable in today’s automotive bus industry along with the other customer oriented industry. In this paper we have explored the dimensional management scope in improving the PQ requirements and expectations by utilizing the dimensional variation analysis (DVA) approach. We have tried to explain the fundamentals of vehicle aggregates fitment process and impact of fitment tolerances as used in DVA model to resolve vehicle packaging issues (critical gaps & clearance variation as per expected no. of vehicles to be
Singh, Vinay Kumar, Dewangan, Ved Prakash, Kumar, Rahul, Deep, Amar
Assessment of Cybersecurity Risks in State-Operated Connected Electric Passenger Buses in India2026-26-06101/16/2026
State Transport Units (STUs) are increasingly using electric buses (EVs) as a result of India's quick shift to sustainable mobility. Although there are many operational and environmental benefits to this development, like lower fuel prices, fewer greenhouse gas emissions, and quieter urban transportation, there are also serious cybersecurity dangers. The attack surface for potential cyber threats is expanded by the integration of connected technologies, such as cloud-based fleet management, real-time monitoring, and vehicle telematics. Although these systems make fleet operations smarter and more efficient, they are intrinsically susceptible to remote manipulation, data breaches, and unwanted access. This study looks on cybersecurity flaws unique to connected passenger electric vehicles (EVs) that run on India's public transit system. Electric vehicle supply equipment (EVSE), telematics control units (TCUs), over-the-air (OTA) update systems, and in-car networks (such as the Controller
Mokhare, Devendra Ashok
Analysis of Energy Consumption for Heating City Electric Buses and Ways to Reduce It2026-26-01561/16/2026
For regions with cold climate, the range of an electric bus becomes a serious restriction to expanding the use of this type of transport. Increased energy consumption affects not only the autonomous driving range, but also the service life of the batteries, the schedule delays and the load on the charging infrastructure. The aim of the presented research is to experimentally and computationally determine the energy consumption for heating the driver's cabin and passenger compartment of an electric bus during the autumn-winter operation period, as well as to identify and analyze ways to reduce this energy consumption. To determine the air temperature in the passenger compartment, a mathematical model based on heat balance equations was used. This model was validated using data from real-world tests. The research was conducted at a proving ground under two conditions: driving at a constant speed and simulating urban bus operation with stops and door openings. The causes of heat loss in
Kozlov, Andrey, Terenchenko, Alexey, Stryapunin, Alexander
Powertrain Optimization of Indian City Electric Bus Using Active Learning Simulation Methodology2026-26-06571/16/2026
Public transport electrification is going to play a massive role in India’s COP26 pledge to achieve net zero emissions by 2070. India plans to electrify 800,000 buses in a push towards 30% EV penetration by 2030. Further encouraged by government incentives under National Electric Bus Program (NEBP), e-Bus market is expected to grow at a CAGR of ~86% annually over the next 5 years. With most OEMs going for fleet electrification for reducing CO2 emissions and to cater to growing demand in Indian cities for cleaner public transport, improving powertrain efficiency and performance of state-of-the-art e-Buses is a natural progression of e-mobility sector development in India. The first step in designing powertrain for an electric city bus is to determine the motor(s) size and transmission specifications (number of gears, gear ratios etc.). Complications arise due to a wider and non-linear operation range of eBus. This study focuses on powertrain optimization for a medium duty electric city
Sandhu, Rouble, Chen, Bicheng, Emran, Ashraf, Xia, Feihong, Lin, Xiao, Berry, Sushil
Smart Grid and Cloud-Based Strategy for EV Pre-Cooling and HVAC Load Management2026-26-00561/16/2026
This paper explains the method of precooling of electric vehicle from grid connected charger reduce load on HVAC and improve the range. HVAC systems are integral part of a commercial EV bus. With the rise of ambient temperatures during various seasons, the load on HVAC System is increasing. Once an Electric vehicle is released from a depot for service, with an initial soaked up ambient vehicle, the HVAC system demands peak power for cooling the interiors which consumes a lot of battery power thus affecting the range. That cause the additional energy consumption required for precooling, which cannot be estimated as it is highly dependent on ambient temperature and range of the vehicle is also dependent on HVAC consumption during summer and peak loads. This paper is proposing a method that uses a special precooling mode which is activated depending on the selection of the vehicle route based on backend application running on cloud. The Application in the cloud checks if the vehicle is
Ganguly, Sutanu, Shukla, Amisha, Jain, Sarika, Patil, Rohan, Sahu, Pritish, Yadav, Ankit, Marskole, Deepa, Amancharla, Naga Chaithanya
Pure Electric Bus of Operational Consulting and Analysis Transit: A Case Study of Wuhu City2025-99-025212/23/2025
As China’s socio-economic progress accelerates, residents’ mobility preferences are growing more varied. Owing to their eco-friendliness, high capacity, fixed routes and low prices, pure-electric buses have become a key component of urban transit. Yet day-to-day service is hindered by low fleet availability, limited daily kilometres and poor service quality, all of which erode operation efficiency. Taking Wuhu’s public transport network as a case study, this paper builds a performance-assessment framework for electric bus routes. Using stop-level topology, vehicle specifications and spatiotemporal passenger-flow data from eight representative routes, the study applies the Analytic Hierarchy Process (AHP). A three-tier hierarchy—goal, criteria and alternatives—is constructed; index weights and pairwise comparison matrices are then computed to rank overall route effectiveness. The findings accurately pinpoint operational bottlenecks and furnish quantitative guidance for adaptive network
Hu, Tingting, Liang, Zijun, Li, Xiaoyan, Zhang, Xinyi, Wang, Mengru, Hu, Yufeng, Jiang, Kang
Current Challenges and Technological Opportunities for Implementing Autonomous Vehicles in Urban Public Transport2025-36-008512/18/2025
Driven by technological advances in artificial intelligence, sensors, connectivity and sustainable mobility, autonomous buses are a reality in many contexts where their application is viable and efficient. The potential of the technology is a clear theme and has been widely discussed over the last two decades, due to various factors such as reducing accidents, increasing operating cost efficiency, improving the efficiency of public transport, reducing environmental impact and offering mobility solutions for increasingly congested urban areas. Due to the implementation of the General Safety Regulation (GSR II) in the European Union, with the aim of reducing traffic accidents and paving the way for fully autonomous vehicles, autonomous vehicles are getting closer to becoming a viable reality on the streets and highways of developed countries [1]. In order to guarantee the necessary safety in autonomous systems, data reliability is fundamental. To this end, it is essential to implement
Gameiro, João, Pirocchi, Amanda, Matias, Brenda, Paterlini, Bruno, Souza, Kerylli de, Angelone, Luca, Gama, Ulisses
The Design and Simulation of Absolute Priority Bus Lane Incorporating Clearance Distance2025-99-036512/17/2025
To alleviate the congestion in general-purpose lanes while exclusive bus lanes remain idle, this paper proposes absolute-priority bus lane design with clearance distance. By establishing specific clearance distances and lane-changing rules, the proposed design method not only enhances overall road utilization efficiency but also ensures unimpaired bus speeds, thereby maintaining bus priority. The simulation is performed based on cellular automaton (CA) model and the results demonstrate that this design is effective when general-purpose lane traffic density ranges between 0-50 vehicles/km/lane, with greater improvements in other non-public vehicle speeds under longer bus dispatch intervals. These results provide a theoretical basis and practical guidance for future bus lane management.
Wei, Liying, Yang, Nan, Gao, Chang
Basic Diagram Model of Mixed Traffic Flow Considering Buses2025-99-030912/17/2025
The emergence of connected and autonomous vehicle (CAV) technologies has ushered in a new era of mixed traffic flow, where CAVs will coexist with human-driven vehicles (HDVs) for the foreseeable future. To investigate the fundamental relationships among flow, density, and speed in this heterogeneous traffic environment, this study develops a comprehensive analytical framework that explicitly accounts for the impact of bus integration in mixed traffic streams. The study initially identifies vehicle classifications and their respective distribution ratios within heterogeneous traffic streams. A fundamental graphical representation of mixed traffic patterns is established, followed by a comprehensive sensitivity evaluation focusing on free-flow velocity parameters within the proposed framework. Subsequently, a micro-level simulation platform is developed utilizing SUMO software. Research outcomes reveal a favorable link between the percentage of integrated self-driving cars and
Xiao, Yujie, Chen, Xiufeng, Wang, Meng, Xu, Ying
Dynamic Resource Allocation and Redundancy Optimization for AFDX Networks2025-99-043312/10/2025
With the continuous development of avionics systems towards greater integration and modularization, traditional aircraft buses such as ARINC 429 and MIL-STD-1553B are increasingly facing challenges in meeting the demanding requirements of next-generation avionics systems. These traditional buses struggle to provide sufficient bandwidth efficiency, real-time performance, and scalability for modern avionics applications. In response to these limitations, AFDX (Avionics Full-Duplex Switched Ethernet), a deterministic network architecture based on the ARINC 664 standard, has emerged as a critical solution for enabling high-speed data communication in avionics systems. The AFDX architecture offers several advantages, including a dual-redundant network topology, a Virtual Link (VL) isolation mechanism, and well-defined bandwidth allocation strategies, all of which contribute to its robustness and reliability. However, with the increasing complexity of onboard networks and multi-tasking
Yang, Lei, Yang, Youzhi, Wang, Zhaoyi, Chang, An, Zhang, Xin, Lin, Zi
Micro-Circulation Bus Route Area Identification under the TOD Concept2025-99-013611/11/2025
Based on the TOD (Transit-Oriented Development) concept, this paper addresses the “last mile” issue in urban public transportation. It proposes a multidimensional decision-making model for identifying micro-circulation bus route areas. By integrating indicators such as the TOD comprehensive index, short-distance demand intensity, and branch network density, relevant data is processed using FME linking ArcGIS. The model combines entropy-weighted TOPSIS and unsupervised consensus clustering analysis techniques, utilizing ArcGIS spatial analysis functions to accurately identify priority deployment areas for micro-circulation buses. Taking Jiangbei District in Chongqing as an example, the model divides the study area into four types of traffic zones: (1) Core high-density areas, which require an increase in micro-circulation bus routes due to extremely high short-distance travel demand; (2) Periphery active population areas, which require flexible shuttle services due to transit gaps and
Jiang, Tao, Jia, Xiaoyan, Li, Jie
Analysis of Maintenance Strategies of Electrical Systems of Electric Bus Charging Station2025-28-040710/30/2025
Charging management has a profound impact on the reliability and safety of electric bus (EB) services. However, the actual charging operation of EB fleets is a critical challenge due to uncertain energy consumption, limited charging resources and other factors. At present there are no operational and maintenance guidelines present for operation of EB charging stations since the running and operation of these facilities are at the initial stages of development. There is a need to develop these strategies that provides smooth operation of these newly developed facilities. In the present work maintenance strategies of electrical systems of Electric bus charging station were designed. The complete maintenance is divided into quarterly and annual maintenance based on the requirements and nature of work for smooth operation. Quarterly Maintenance is devised on detecting early signs of wear through visual inspections of key components, including transformers and ventilation systems while
Soam, Kumaresh, Vashist, Devendra
Battery Innovation Key for Commercial and Off-Highway EVsTBMG-5387410/1/2025
In the commercial and off-highway vehicle industry, the transition from internal combustion engines to hybrid and electric alternatives is underway. In 2024, sales of electrified trucks reached more than 97,000, while buses notched 72,000 sales, according to the International Energy Agency (IEA). Estimates for 2025 suggest these numbers will be even greater.
Analyzing and Simulating Energy Consumption of Battery Electric Transit Buses in Real-Driving Conditions02-19-02-00079/29/2025
Analyzing and accurately estimating the energy consumption of battery electric buses (BEBs) is essential as it directly impacts battery aging. As fleet electrification of transit agencies (TAs) is on the rise, they must take into account battery aging, since the battery accounts for nearly a quarter of the total bus cost. Understanding the strain placed on batteries during day-to-day operations will allow TAs to implement best-use practices, continue successful fleet electrification, and prolong battery life. The main objective of this research is to estimate and analyze the energy consumption of BEBs based on ambient conditions, geographical location, and driver behavior. This article presents a model for estimating the battery energy consumption of BEBs, which is validated using the data on federal transit bus performance tests performed by Penn State University and experimental aggregated trip data provided by the Central Ohio Transit Authority (COTA). The developed simulator aims
Shiledar, Ankur, Shanker, Anirudh, Pulvirenti, Luca, Di Luca, Giuseppe, Akintade, Rebeccah, Rizzoni, Giorgio
BEV Powertrain Analytics: Network Pulse Ringing – Ripple Currents - NVH Topics2025-24-01349/7/2025
The interaction of electric, electronic (E/E) and mechanical components defines the quality of a BEV’s powertrain. Component selection, their integration and calibration aim at meeting legal requirements for EMC and safety as well as competitive targets for efficiency, NVH and driving comfort. These tasks in particular need attention on electromagnetic events on the DC bus, the high-power electronics of inverters, the e-motors, and the drive shaft. Each component within this environment is defined by its electromechanical features with variabilities selected from a large set of operating parameters. Consequently, a complete powertrain and its controllers give rise to endless combinations for powertrain operation. How to understand and avoid risk laden and ineffective parameter options, how to find powertrain control parameters for safe, efficient and comfortable operation? And how to find solutions within competitive development timeframes? Particular issues include high voltage risks
Winklhofer, Ernst, Berglez, Manuel, Kiss, Gergely, Platzer, Thomas
SAE TOMORROW TODAY - How Buses Are Leading the Self-Driving Revolution135298/8/2025
Thanks to their fixed routes and predictable environments, commercial vehicles like airport shuttles and public transit buses are proving to be the perfect match for SAE Level 4 automation. One company at the forefront of this transformation is Fusion Processing, a global leader in automated driving, situational awareness, and control systems. Fusion has logged over 90,000 kilometers of on-highway autonomous driving -- more than any other AV company in Europe. Their innovative technologies, including CAVstar and CycleEye, are already delivering tangible benefits in real-world commercial vehicle fleets, from freight to passenger services. To learn more, we sat down with Jim Hutchinson, Co-Founder and CEO, to discuss the future of transit and how Fusion is working to scale autonomous buses globally. We'd love to hear from you. Share your comments, questions and ideas for future topics and guests to podcast@sae.org. Don't forget to take a moment to follow SAE Tomorrow Today--a podcast
Patterson, Lori
Impact of Battery Electric Conversion on Rollover Safety of Large Passenger Buses per UN ECE R6609-13-02-00098/1/2025
The electric conversion of a large passenger vehicle was investigated, in which the internal combustion engine and associated components were replaced by electric powertrain components. As this will have an influence on the rollover safety performance of the vehicle, compliance to the requirements of UN ECE Regulation No.66 was assessed. The vehicle geometry was captured through physical inspection. The unladen kerb mass of the vehicle was experimentally determined as 10660 kg. This mass excludes the mass of occupants as the vehicle is not fitted with occupant restraints. The location of the center of gravity was estimated using a representative CAD model. The center of gravity is located at a distance of 3580 mm behind the front axle and at a height of 1195 mm above the ground. An implicit nonlinear finite element (FE) analysis was conducted to quantify the energy absorption capability of a rollover hoop. This value was calculated as 5.65 kJ for a single rollover hoop and 67.80 kJ for
Raats, Daniel James, Venter, Gerhard, Bredell, Johann
Simulation-Based Investigation and its Experimental Validation of the Thermal Behaviour of a Battery Electric City Bus2025-01-02667/2/2025
Electrification of city busses is an important factor for decarbonisation of the public transport sector. Due to its strictly scheduled routes and regular idle times, the public transport sector is an ideal use case for battery electric vehicles (BEV). In this context, the thermal management has a high potential to decrease the energy demand or to increase the vehicles range. The thermal management of an electric city bus controls the thermal behaviour of the components of the powertrain, such as motor and inverters, as well as the conditioning of the battery system and the heating, ventilation, and air conditioning (HVAC) of the drivers’ front box and the passenger room. The focus of the research is the modelling of the thermal behaviour of the important components of an electric city bus in MATLAB/Simscape including real-world driving cycles and the thermal management. The heating of the components, geometry and behaviour of the cooling circuits as well as the different mechanisms of
Schäfer, Henrik, Meywerk, Martin, Hellberg, Tobias
Minimum Sound Testing of Medium- and Heavy-Duty Electric Vehicles2025-01-50446/27/2025
The acoustic performance of seven vehicles was evaluated according to Canadian Motor Vehicle Safety Standard 141 (CMVSS 141), which governs minimum required sound levels for hybrid and electric vehicles with a gross vehicle weight rating (GVWR) of 4536 kg (10,000 lb) or less. To better understand the sound profiles of medium-duty electric vehicles (MDEVs) and heavy-duty electric vehicles (HDEVs), the sound emissions of two light-duty electric vehicles (LDEVs), one MDEV, three HDEVs, including an electric transit bus, and one heavy-duty internal combustion engine (HD ICE) vehicle were compared. The sound emissions of the MDEV and HDEVs were quieter than the HD ICE vehicle and comparable to that of the LDEVs equipped with auxiliary speakers. The MDEV with its auxiliary speaker turned off and all three HDEVs without auxiliary speakers met CMVSS 141 requirements in reverse gear and at speeds of 20 km/h and 30 km/h. The MDEV, though not subject to CMVSS 141, failed to meet the minimum sound
Sharma, Vinay, Larocque-Legros, Marc-André, Weston, Cole, Schulte, Andrew, Christenson, Martha, Rooney, Anne
Overview of Indian Government Policies, Regulations and Automotive Company Strategies toward Net-zero Emissions2025-01-01846/16/2025
The automotive sector in India is undergoing a transformation, driven by government policies and regulations aimed at achieving net-zero carbon emissions. In alignment with global climate goals, the Indian government has set ambitious targets to reduce greenhouse gas emissions, with a focus on promoting Electric Vehicles (EVs) and Hydrogen Fuel Cell Vehicles (FCVs). Initiatives like the Faster Adoption and Manufacturing of Hybrid and Electric Vehicles (FAME) Scheme, along with tax incentives, subsidies, and charging infrastructure development, are designed to accelerate the adoption of cleaner vehicles. The introduction of stricter emission standards and the National Electric Mobility Mission Plan (NEMMP) further underscores the push toward sustainable mobility. In response, Indian automotive companies are shifting strategies to align with these government directives. Major players are significantly increasing investments in EV technology, focusing on enhancing battery performance
Patil, Nikhil Nivrutti, Saurabh, Saurabh, Bhardwaj, Rohit, Gawhade, Ravikant, Gadve, Dhananjay, Amancharla, Naga Chaithanya
Noise Management in Electric Vehicle Compressors for Superior Cabin Comfort2025-01-01916/16/2025
This research addresses the issue of noise, vibration, and harshness (NVH) in electric buses, which can hinder their widespread adoption despite their environmental benefits. With the absence of traditional engines, NVH control in electric vehicles focuses on auxiliary components like the air compressor. In this study, the air compressor was identified as a major source of vibration, causing harsh contact between its oil sumps and mounting bracket. Analyzing the vibrations revealed that the sump and bracket were not moving freely, increasing noise. Modifying the bracket design to allow more movement between the components successfully reduced both noise and vibration. The paper details the experimental process, findings, and structural damping methods to mitigate NVH in electric buses.
Paroche, Sonu, Patel, Shubhanshi, Patidar, Ashok Kumar
Automotive Engineering: June 202525AUTP066/5/2025
Balancing the scales in Dakar Here's how M-Sport engineers removed some weight - and added some elsewhere - to produce a podium-winning vehicle. Sealing the future of in-wheel motors: low friction and maximum protection V-seals and cassette seals offer critical protection from environmental influences and are helping in-wheel motors set new benchmarks. Taiwan suppliers look around the world for solutions Tariffs are forcing Taiwanese companies to rethink their plans, but it could be worse. U.S. states focus on Taiwan as trade war continues Taiwan's role in the global automotive supply chain continues to increase, which is one reason so many U.S. states are on site. Tariff challenges, EV advances at 360 Mobility We check in on Foxconn, Master Bus, PEWC and NUK at Taiwan's big trade show for the transportation industry. Editorial Off we go Supplier Eye Investment certainty is critical GM picks LMR as its future affordable battery technology Slate unveils bare-bones EV mini truck for
Methods to Reduce Transmission of Airborne Viruses in a Bus Cabin02-18-04-00215/19/2025
Public buses can be high-risk environments for the transmission of airborne viruses due to the confined space and high passenger density. However, advanced cabin air control systems and other measures can mitigate this risk. This research was conducted to explore various strategies aimed at reducing airborne particle transmission in bus cabins by using retrofit accessories and a redesigned parallel ventilation system. Public transit buses were used for stationary and on-road testing. Air exchange rates (ACH) were calculated using CO2 gas decay rates measured by low-cost sensors throughout each cabin. An aerosol generator (AG) was placed at various locations inside the bus and particle concentrations were measured for various experiments and ventilation configurations. The use of two standalone HEPA air filters lowered overall concentrations of particles inside the bus cabin by a factor of three. The effect of using plastic “barriers” independently showed faster particle arrival times
Lopez, Brenda, Swanson, Jacob, Dover, Kevin, Renck, Evan, Chang, M.-C. Oliver, Jung, Heejung
Structural Strength Evaluation of the Lightweight Frame of Bus Passenger Seat with High-Tensile Material and Analysis of the Importance of Independent Variables by Regression02-18-04-00225/10/2025
This study aims to develop a lightweight bus passenger seat frame by conducting structural nonlinear finite element analysis (FEA) on various thickness combinations of seat frame components to identify the optimal configuration. The thicknesses of critical structural members that primarily bear the load when force is applied to the seat frame were selected as independent variables, while stress on each component and compliance with ECE R14 seatbelt anchorage displacement regulations were set as dependent variables. A regression analysis was performed to calculate the importance of each component and analyze the influence of each design variable on the dependent variables. Strain gauges were attached to critical areas of the actual seat frame to conduct a seatbelt anchorage test, and simulations under identical conditions were performed using the nonlinear FEA software (LS-DYNA) to validate the reliability of the analysis results. The optimized seat frame exhibited a maximum stress of
Ko, Yeong Gook, Cho, Kyu Chun, Lee, Ji Sun, Kang, Ki Weon
Electric Bus NVH Challenges and Refinement Using Innovative Approach2025-01-00805/5/2025
The trend towards electrification propulsion in the automotive industry is highly in demand due to zero-emission and becoming more significant across the world. Battery electric vehicles have lower overall noise as compared to conventional I.C Engine counterparts due to the absence of engine combustion and mechanical noise. However, other narrowband and tonal noises are becoming dominant and are strongly perceived inside the cabin. With the ongoing push towards electrification, there is likely to be increased focus on the noise impact of gearing required for the transmission of power from the electric motor to the road. Direct coupling of E-motors with Axle has resulted in severe tonal noises from the driveline due to instant e-motor torque ramp up from 0 rpm and reverse torque on driving axle during regenerative braking. The tonal noises from the rear axle during vehicle running become very critical for customer perception. For automotive NVH engineers, it has become a challenge to
Doshi, Sohin, Kalsule, Dhanaji, Sawangikar, Pradeep, Suresh, Vineeth, Sharma, Manish
The Applications of Acoustic Black Holes to Attenuation of Coach/Bus Frame Structure Vibrations2025-01-00655/5/2025
Basic structures of vehicle frames、aircraft fuselages and ship hulls are made of beams、columns and trusses. If Acoustic Black Holes(ABH) are carefully arranged alongside with the wave propagation paths in those structures, the wave propagation paths could be changed at NVH engineers’ will and the structure vibrations can be reduced. Two kinds of ABHs are used in this paper: one is ABH made of Polyurethane(PU), other one is ABH composed of several steel plate 1D ABH stacked up in parallel. Three structures are used to test the effectiveness of ABHs for vibration reductions: a squared hollow sectional steel commonly used in motorcoach/bus chassis and frame structures, a simple frame for motorcoach airbag suspension and a 12m chassis structure. The attached ABHs show a great vibration attenuation in terms of transfer functions on the basic structure element for a motorcoach. The lateral, vertical and longitudinal transfer functions for steel ABHs were greatly reduced from 13.2~14.7 dB
Xu, Chuanyan, Wang, Jianjun, Xing, Qisen, Chen, Hengbin, Huang, Xianli
Influence of Coolant Properties on Battery Thermal Management in Electric Buses during Cold Starts02-18-03-00134/24/2025
Improving electric vehicles’ overall thermal management strategy can directly or indirectly improve battery efficiency and vehicle range [1]. In this study, the effect of the coolant type used in BTMS (battery thermal management system) units used for heating batteries in cold weather conditions was investigated in electric buses. In this investigation, tests were performed with two types of antifreeze, which have different characteristics. The study evaluated the impact of coolant flow, BTMS circulation pump performance, and battery heating using these two types of antifreeze in the BTMS coolant line. In addition to carrying out tests, 1D computational fluid dynamics models’ simulations were carried out for both types of antifreeze, and the results were validated with experimental findings. In this study, a 12-m EV Citivolt vehicle of Anadolu Isuzu was used for tests. As a result, it was observed that differences in the properties of the antifreeze that is used in BTMS coolant line
Çetir, Özgür, Birgül, Çağrı Emre
Single Conductor Cable for Heavy-Duty Applications - Truck and BusJ2549_202504 (Current)4/16/2025
This SAE Standard establishes the minimum construction and performance requirements for single conductor cable for use on trucks, trailers, and converter dollies.
Truck and Bus Electrical Systems Committee
Taxonomy and Definitions for Truck and Bus Automated Vehicle SystemsJ3150_202504 (Current)4/14/2025
This document provides definitions, terminology, and classifications for automated truck and bus vehicle applications. Vehicles covered by this document are those with a GVWR of more than 10000 pounds and where each vehicle utilizes driving automation systems that perform part or all of the driving task on a sustained basis and that range in level from some driving automation to full driving automation. The document also provides levels of driving automation that apply to the driving automation feature engaged in any given instance of operation of an equipped vehicle. A vehicle may be equipped with a driving automation system that is capable of delivering multiple driving automation features that perform at different levels; the level of driving automation exhibited in any given instance is determined by the feature(s) that are engaged. This document provides guidance for the elements of the dynamic driving task (DDT) for a truck or bus equipped with an Automated Driving System (ADS).
Truck and Bus Automation Safety Committee
A Low-Entry Bus Body Structure Performance under the Conditions of the New Car Assessment Program Frontal Crash Tests09-13-02-00074/9/2025
The New Car Assessment Program (e.g., US NCAP and EuroNCAP) frontal crash tests are an essential part of vehicle safety evaluations, which are mandatory for the certification of civil means of transport prior to normal road exploitation. The presented research is focused on the behavior of a tubular low-entry bus frame during a frontal impact test at speeds of 32 and 56 km/h, perpendicular to a rigid wall surface. The deformation zones in the bus front and roof parts were estimated using Ansys LS-DYNA and considered such factors as the additional mass (1630 kg) of electric batteries following the replacement of a diesel engine with an electric one. This caused stabilization of the electric bus body along the transverse axis, with deviations decreased by 19.9%. Speed drop from 56 to 32 km/h showed a reduction of the front window sill deformations from 172 to 132 mm, and provided a twofold margin (159.4 m/s2) according to the 30g ThAC criterion of R80. This leads to the conclusion about
Holenko, Kostyantyn, Dykha, Aleksandr, Koda, Eugeniusz, Kernytskyy, Ivan, Royko, Yuriy, Horbay, Orest, Berezovetska, Oksana, Rys, Vasyl, Humeniuk, Ruslan, Berezovetskyi, Serhii, Chalecki, Marek
Learning-Based Energy Management Strategy of Fuel Cell City Buses Considering Power Source Degradation02-18-02-00124/2/2025
Fuel cell vehicles (FCVs) offer a promising solution for achieving environmentally friendly transportation and improving fuel economy. The energy management strategy (EMS), as a critical technology for FCVs, faces significant challenges of achieving a balanced coordination among the fuel economy, power battery life, and durability of fuel cell across diverse environments. To address these challenges, a learning-based EMS for fuel cell city buses considering power source degradation is proposed. First, a fuel cell degradation model and a power battery aging model from the literature are presented. Then, based on the deep Q-network (DQN), four factors are incorporated into the reward function, including comprehensive hydrogen consumption, fuel cell performance degradation, power battery life degradation, and battery state of charge deviation. The simulation results show that compared to the dynamic programming–based EMS (DP-EMS), the proposed EMS improves the fuel cell durability while
Song, Dafeng, Yan, Jinxing, Zeng, Xiaohua, Zhang, Yunhe
Optimizing Charging Infrastructure Management for Enhanced Grid Resilience2025-01-81204/1/2025
This study addresses the challenges of electrifying heavy-duty vehicle fleets, particularly school buses, by focusing on the development of dedicated depot charging infrastructure and grid resilience. A key challenge is managing recharging limitations while considering grid resilience in the electrification of school bus fleets. Using real operational data, the study introduces a two-phase approach to optimize both charging infrastructure and scheduling. In the first phase, the optimal number of chargers is determined to ensure sustainable fleet operations. In the second phase, charging schedules are refined to reduce peak power demand and improve grid resilience. Experimental results demonstrate that approximately half the fleet size is required in chargers, with distributed charging and peak shaving strategies reducing peak power demand by 20% to nearly 45%. These findings offer practical insights for fleet managers, grid operators, and policymakers on enhancing grid resilience and
Moon, Joon, Hanif, Athar, Ahmed, Qadeer
Lightweight Optimization of an Electric Bus Body Frame Based on the C 2 oDE Algorithm2025-01-86544/1/2025
In this work, design optimization for the lightweight of the body frame of a commercial electric bus with the requirements of stiffness, strength and crashworthiness is presented. The technique for order preference by similarity to ideal solution (TOPSIS) is applied to calculate the components that have a great impact on the output response of the static modal model and the rear-end collision model. The thickness of the five components with the highest contribution in the two models is determined as the final design variable. Design of experiment (DOE) is carried out based on the Latin Hypercube sampling method, and then the surrogate models are fitted by the least squares regression (LSR) method based on the DOE sampling data. The error analysis of the surrogate model is carried out to determine whether it can replace the finite element (FE) model for optimization, then the optimization scheme for lightweight optimization of electric bus frame is implemented based on the algorithm of
Yang, Xiujian, Tian, Dekuan, Liu, Jiaqi, Cui, Yan, Lin, Qiang
YRSRA: Yaw and Roll Stable Region Analytics for Ground Vehicle System with 5G-V2X2025-01-87994/1/2025
Since most of the existing studies focus on the identification of the yaw stable region, but ignore the identification of the roll stable region, this article presents a software tool YRSRA for calculating both the yaw and roll stable region for ground vehicle system with 5G-V2X. And the frequency of rollover instability of commercial vehicles such as trucks and buses is not low, and the cost of rollover accidents is often greater than the cost of yaw instability accidents. Therefore, it is necessary to identify the stability region of yaw and roll at the same time. Firstly, the iterative model of yaw rate and slip angle is constructed through deducing the two-degree-of-freedom vehicle dynamics. Secondly, the load transfer ratio (LTR) is coded with given yaw rate and slip angle. Thirdly, several Illustrative examples are depicted, such as variation of steer angle, road adhesion coefficient and vehicle speed. The software features an easy to generate yaw and roll stability region by on
Tu, Lihong, Zeng, Dequan, Zhang, Zhouping, He, Qixiao, Zhao, Shuqi, Sun, Jing, Wang, Aichun, Yu, Qin, Ming, Jinghong, Wang, Xiaoliang, Hu, Yiming
Analysis of the Design Space for Battery- and Fuel Cell-Powered Medium- and Heavy-Duty Trucks Based on a Simplified Cost of Ownership Evaluation2025-01-86004/1/2025
Diverse solutions will likely be needed to decarbonize the commercial truck sector in the United States. Battery-powered vehicles play a predominant role but in some cases, fuel cell trucks are more advantageous for the consumer. This study examines several medium- and heavy-duty applications designed for different driving range requirements to identify the design space where battery and fuel cell trucks are attractive. Also considered are the impacts of purchase price, fuel cost, and vehicle usage. We examine the top 10 truck classes as well as bus applications based on vehicle population, fuel usage, and driving distances. We assume a 2030 scenario where both batteries and FC systems become less costly and more efficient, as targeted by the U.S. Department of Energy. Even for smaller-class vehicles, where battery electric vehicles are expected to be the most economical among clean vehicle solutions, the results are not straightforward. Based on vehicle design, usage, and external
Vijayagopal, Ram, Birky, Alicia
Activity and Performance of Zero and Near-Zero Emissions Port Equipment for Emissions Reduction in the Maritime Sector2025-01-85394/1/2025
Marine ports are an important source of emissions in many urban areas, and many ports are implementing plans to reduce emissions and greenhouse gases using zero-emission cargo handling equipment. This paper evaluates the performance and activity profiles for various zero-emission (ZE) cargo transport equipment being demonstrated at different ports in California. This included 23 battery-electric (BE) 8,000 lb. (8K) and 36,000 lb. (36K) forklifts, a BE railcar mover, and an electrified rubber-tired gantry crane (eRTG). The study focused on evaluating the performance of the ZE equipment in terms of activity patterns and the potential emissions reductions. Data loggers were used to collect activity data, including hours of use, energy consumption, and charging information over periods from 6 to 21 months. The results showed that the BE forklifts, BE railcar mover, and the eRTG averaged 2-3 hours, 5 hours, and 14 hours of use per day of operation, respectively. The average energy use for
Frederickson, Chas, Vu, Alexander, Makki, Maedeh, Johnson, Kent, Durbin, Thomas, Burnette, Andrew, Huang, Eddy, Alvarado, Erica, Rao, Leela
Mitsubishi Fuso repurposes EV batteries for energy storage systems25TOFHP04_084/1/2025
Mitsubishi Fuso Truck and Bus has announced it will conduct a joint demonstration of its Battery 2nd Life initiative this year. This initiative will be jointly conducted with CONNEXX Systems and will repurpose used batteries from Mitsubishi eCanter trucks to build energy storage systems. According to Mitsubishi, CONNEXX will remove the used batteries from end-of-life eCanters and repurpose them as power sources for what CONNEXX has dubbed its EnePOND EV Charger energy storage systems. These units have integrated EV chargers developed by CONNEXX that can reportedly reduce the load on the existing power grid while allowing for DC fast charging of multiple EVs simultaneously. CONNEXX also noted that these units enable EV charging during power outages.
Wolfe, Matt
Bus Arrival Time Prediction Using Decomposition Technology and Deep Learning2025-01-71413/19/2025
Bus arrival time prediction is an important part of urban bus operation, which maintains the stability and punctuality of the bus system. Providing accurate public transport travel service information can attract more public transport travelers, thereby improving the public transport share. By knowing the arrival time of the bus in advance, travelers can arrange their travel time more effectively and reduce their waiting time at bus stops. In addition, accurate bus arrival time also contributes to the design, development and management of the bus system, promoting better resource scheduling and lower operating costs. However, the prediction based on historical data cannot cope with the complex changes of real-time traffic conditions and meet the requirements of public transportation information system. Therefore, current research is increasingly focused on improving the accuracy of real-time prediction, while prediction models are exploring and adjusting to adapt to complex traffic
Wang, Suyi, Li, Tiezhu, Chen, Wanjiang
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