Browse Topic: Public transportation systems

Items (1,149)

Vehicle to Vehicle Recharge and Power Sharing for Modular Public Transportation Systems: Design and Testing of the UNIFI fleet at ENEA CASACCIA Research Center

2025-32-0095To be published on 11/03/2025

An optimized and capillary diffusion of sustainable public transportation systems often involve the availability of modular and scalable solutions that can be easily adapted to a variable transportation demand in a very fast way or even in real-time. For this reason, there is a growing industrial interest for the development of modular transportation systems composed by relatively small electric units (small modular e-buses with installed battery power of about 15kWh) that should be used to assemble smart intelligent compositions according to transportation demand of customers. University of Florence and Enea Research Center of Roma Casaccia have developed a fleet of electric mini-Buses for the testing of technologies related to this kind of applications (assisted or autonomous drive functionalities, motion, and trajectory controllers, coordinated smart power management etc.). In this work attention is focused on design and testing of the energy management system that assure the

Alessandrini, Adriano, Berzi, Lorenzo, Fabbri, Marco, Franci, Michael, Gulino, Michelangelo Santo, Pugi, Luca, Ortenzi, Fernando, Vitiello, Francesco

Influence of MPC based Driver Types on the Energy Consumption of Battery Electric Vehicles

2025-24-0113To be published on 09/07/2025

Electric vehicles are increasingly important to reducing emissions and promoting sustainable mobility. Despite their advantages over conventional vehicles, the energy consumption of electric vehicles is heavily influenced by various factors such as driving behavior, elevation profile, and environmental conditions. In particular, the driving style plays a crucial role in determining range and energy consumption. This influence is also observed in the context of the Interreg project FreeE-Bus. This project focuses on the development of optimized charging management for electric buses in the public transport system of the Lake Constance region. Due to strict data protection regulations that prevent a detailed analysis of driver data, assessing the impact of driving styles is difficult. This paper addresses this issue by developing an innovative driver model that simulates different driver types and analyzes their effects on energy consumption. The driver model employs a Model Predictive

Konzept, Anja, Reick, Benedikt, Miller, Marius, Rautenberg, Philip, Störzer, Martin

SAE TOMORROW TODAY - How Buses Are Leading the Self-Driving Revolution

1352908/08/2025

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

The Automation Concept of the U-Shift II Vehicle

2025-01-0281

07/02/2025

Autonomous driving technology enables new and innovative driverless vehicle concepts to emerge, like U-Shift. Designed from the ground up, the U-Shift II platform, called driveboard, exemplifies the advantages of separating a vehicle’s driving capability from the intended transportation task. It allows different so-called capsules, such as public transport or cargo, to be transported using the same U-shaped driving platform. The driveboard can change the capsules autonomously, thus providing high flexibility for fleet operators. This novel approach introduces new challenges to the task of autonomous driving. On one hand, changing sensor and vehicle configurations, e.g., when transporting a capsule with its own sensors to compensate for occlusions of the driveboard sensors by the capsule itself, requires an adaptive approach to environmental perception. On the other hand, different environments and driving tasks, as well as the augmented motion capabilities of the driveboard, require

Buchholz, Michael, Wodtko, Thomas, Schumann, Oliver, Authaler, Dominik

Simulation-Based Investigation and its Experimental Validation of the Thermal Behaviour of a Battery Electric City Bus

2025-01-0266

07/02/2025

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

Low-Temperature Coolant Circuit Nomenclature and Applications

J3136_202506 (Current)

06/17/2025

The document provides clarity related to multiple temperature coolant circuits used with on-highway and off-highway, gasoline, and light-duty to heavy-duty diesel engine cooling systems, or hybrid vehicle systems. These multiple temperature systems include engine jacket coolant plus at least one lower temperature system. Out of scope are the low temperature systems used in electric vehicles. This subject is covered in SAE J3073. Note that some content in SAE J3073 is likely to be of interest for hybrid vehicles. Out of scope are the terms and definitions of thermal flow control valves used in either low-temperature or high-temperature coolant circuits. This subject is covered in SAE J3142.

Cooling Systems Standards Committee

3D-Printed Porous Media Combined with Biomimetic Distributor for Small-Scale Polymer Electrolyte Membrane Fuel Cells

2025-01-0196

06/16/2025

This study presents a novel biomimetic flow-field concept that integrates a triply periodic minimal surface (TPMS) porous architectures with a hierarchical leaf-vein-inspired distribution zone, fabricated through 3D printing. By mimicking natural transport systems, the proposed design enhances oxygen delivery and water removal in proton exchange membrane fuel cells (PEMFCs). The results showed that I-FF and G-FF significantly improved mass transport and water management compared to conventional CPFF. The integrated design I-FF-LDZ achieves up to 32% improvement in power density at 1.85 A/cm2@0.4 V and delays the onset of mass transport losses. The study also reveals that optimizing the volume fraction Vf significantly affects gas penetration, with lower Vf (30%) improving performance in the mass-limited region. These findings underscore the promise of nature-inspired, 3D-printed flow-field architectures in overcoming key transport limitations and advancing the scalability of next

Ho-Van, Phuc, Lim, Ocktaeck

Methods to Reduce Transmission of Airborne Viruses in a Bus Cabin

02-18-04-0021

05/19/2025

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

Local and Global Entropy Generation of Topographically Optimized Porous Reactors in Reaction-Diffusion Systems Considering Coupling Effects between Heat and Mass Transfer

2024-32-0069

04/18/2025

As the automotive sector shifts towards cleaner and more sustainable technologies, fuel cells and batteries have emerged as promising technologies with revolutionary potential. Hydrogen fuel cell vehicles offer faster refueling times, extended driving ranges, and reduced weight and space requirements compared to battery electric vehicles, making them highly appealing for future transportation applications. Despite these advantages, optimizing electrode structures and balancing various transport mechanisms are crucial for improving PEFCs’ performance for widespread commercial viability. Previous research has utilized topology optimization (TO) to identify optimal electrode structures and attempted to establish a connection between entropy generation and topographically optimized structures, aiming to strengthen TO numerical findings with a robust theoretical basis. However, existing studies have often neglected the coupling of transport phenomena. Typically, it is assumed that a single

Tep, Rotanak Visal Sok, Long, Mengly, Alizadeh, Mehrzad, Charoen-amornkitt, Patcharawat, Suzuki, Takahiro, Tsushima, Shohji

Bus Arrival Time Prediction Using Decomposition Technology and Deep Learning

2025-01-7141

03/19/2025

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

Research on Taxiing Path Planning of Hub Airport Based on Dijkstra Algorithm

2025-01-7198

02/21/2025

Aiming at the problem of insufficient capacity of taxiways in hub airports, which combine the safety interval, conflict resolution and fair principles, a taxiway planning model is established by taking the shortest taxiway as the optimisation goal, considering fuel consumption and exhaust emissions. Dijkstra algorithm is used to transform the taxiing path into an adjacency matrix, and conflict resolution is carried out in a weighted way. Under the premise of ensuring zero conflict of taxiways, the total taxiing distance is reduced. Based on actual operational data from a hub airport in China, the results show that the proposed taxiing path planning method is feasible, shortening the aircraft taxiing distance and improving the surface taxiing efficiency.

Feng, Bocheng, Qi, Xinyue, Zhang, Hongbin

A Real-Time Multiplayer SUMO-Unity Co-Simulation Platform for Vehicle-Aircraft Coordinated Operation

2025-01-7197

02/21/2025

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

Network Feature-Enriched Machine Learning Model for Predictive Analytics of Flight Departure Delays in Smart Aviation

2025-01-7133

02/21/2025

Due to the crucial impact on flight scheduling, airline planning, and airport operations, flight departure delay prediction has emerged as a severe and prominent issue within the realm of smart aviation systems. Accurately predicting flight departure delay durations constitutes a crucial aspect of smart aviation management. Such predictive capability empowers aviation authorities and airport regulators to implement optimized air traffic control strategies, mitigating delays and elevating airport operational efficiency, while enhancing the satisfaction of travelers. The methodology employed in flight delay prediction has undergone substantial evolution in recent years, progressing from rudimentary statistical models to more sophisticated and intricate machine learning models. In this study, we introduce a novel machine learning model enriched with network features and grid search-based parameter selection for advanced predictive analytics of flight departure delays. This model

Chen, Linxian, Shen, Xiuyu, Chen, Jingxu, Liu, Xize

Modeling Internal Node Impedance in High-Speed Rail Passenger Hubs Based on Queuing Theory

2025-01-7172

02/21/2025

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

Traffic Flow Simulation Analysis of Mixed Traffic Flow Involving CAVs and Human-Driven Vehicles in Urban Work Zones

2025-01-7187

02/21/2025

With the acceleration of urbanization, developing public transportation is an important means to alleviate travel pressure and traffic congestion in cities. Work zones that occupy urban road resources affect normal vehicle operations, leading to reduced vehicle efficiency. Based on this, the paper conducts research on traffic flow modeling and simulation analysis for work zones in a vehicle-road coordination environment. Based on the Gipps model and the SCAT model, optimizations and improvements were made to the following and lane-changing rules for three types of vehicles: human-driven vehicles (HVs), autonomous and connected vehicles (CAVs), and buses. Using cellular automata theory, it constructs a running model suitable for mixed traffic flow vehicles in work zones. MATLAB software is utilized to simulate the operation process of vehicles under work zone scenarios, analyzing changes in traffic flow from two directions: road geometric conditions (speed limits) and traffic flow

Xie, Rongkai, Sun, Bo, Zheng, Yunchao, Liao, Meixian, Zhang, Wendi, Li, Rui

Privacy Risk Assessment of Travel Trajectories in Metro AFC Data

2025-01-7214

02/21/2025

The rapid expansion of metro systems in major cities worldwide has resulted in the accumulation of vast amounts of travel data through Automatic Fare Collection (AFC) systems. While this data is crucial for enhancing and optimizing transportation networks, it also raises significant concerns regarding passenger privacy due to the potential exposure of individual travel patterns. In this paper, we propose a novel privacy risk assessment model aimed at quantifying the uniqueness of travel trajectories and evaluating the associated privacy threats. Utilizing AFC data from Chengdu collected in March 2021, we first employ an information entropy approach to assess the uniqueness of travel trajectories across different time granularities. We then apply the K-Means clustering algorithm to classify these trajectories into categories based on their uniqueness levels, enabling us to investigate how factors like travel time and routes influence trajectory uniqueness. To further understand the

Fan, Xiaoting, Qu, Xu, Yang, Hongtai

A Cooperative Control Approach of Transit Signal and Trajectory Optimization for Bus Priority at Connected Intersection

2025-01-7196

02/21/2025

This paper proposes a cooperative control of transit signal priority and speed guidance strategy for connected buses at intersections, which aims to reduce travel delays and improve driving comfort. The connected bus could pass the intersection with the green light while minimizing the impact on the social traffic flow or reduce bus waiting time at intersections. The cooperative optimal problem is described as a mixed-integer programming problem. Serval simulation tests are conducted in SUMO platform, which is proved that the total passenger delay is reduced and the average vehicle cumulative queue length at intersections is reduced, and the bus travel efficiency is improved.

Wang, Xiaoliang, Ma, Shufang, Yu, Qin, Song, Wen, Peng, Hongrui, Hu, Yiming

Dynamic Evaluation Method for Public Transport Operation Indicators Based on Rank Transformation

2025-01-7219

02/21/2025

This study presents a method to evaluate the daily operation of traditional public transportation using multi-source data and rank transformation. In contrast with previous studies, we focuses on dynamic indicators generated during vehicle operation, while ignoring static indicators. This provides a better reference value for the daily operation management of public transport vehicles. Initially, we match on-board GPS data with network and stop coordinates to extract arrival and departure timetable. This helps us calculate dynamic operational metrics such as dwell time, arrival interval, and frequency of vehicle bunching and large interval. By integrating IC card data with arrival timetable, we can also estimate the number of people boarding at each stop and derive passenger arrival time, waiting time, and average waiting time. Finally, we developed a comprehensive dynamic evaluation method of public transportation performance, covering the three dimensions: bus stops, vehicles, and

Zhou, Yang, Shao, Yichang, Han, Zhongyi, Ye, Zhirui

A Step Toward Safer X-Rays with New Detector Technology

TBMG-52295

01/01/2025

X-rays are a common component of diagnostic testing and industrial monitoring, used for everything from monitoring your teeth to scanning your suitcase at the airport. But the high-energy rays also produce ionizing radiation, which can be dangerous after prolonged or excessive exposures. Now, researchers publishing in ACS Central Science have taken a step toward safer x-rays by creating a highly sensitive and foldable detector that produces good quality images with smaller dosages of the rays.

Transit Bus System Electrification Transition Planning Review

2024-36-0067

12/20/2024

The world’s commitment towards the mitigation of climate changes has driven many sectors into an effort to reduce their carbon footprint. The transit bus sector, which currently strongly relies on diesel fueled buses, is challenged to reduce its carbon footprint, as well as to reduce the emission of criteria pollutant and noise, which negatively affect the world cities’ population, especially those living nearby the large transit bus corridors. In this context, the Battery Electric Buses (BEB), has been set as the transit sector’s workhorse for reaching the global, regional and local environmental targets. However, despite the relative maturity level of both the electric powertrain and the energy storage devices (ESD) technologies, the bus electrification transition is a disruptive process, from both a technological, operational and managerial standpoint, which might take into account both the (electrical) infrastructure, as well as the operational customization requirements. Moreover

Barbosa, Fábio Coelho

Influence of the COVID-19 Pandemic on the Transition Process to Electronic Ticketing in Public Transport: A Case Study in a Brazilian City

2024-36-0020

12/20/2024

The COVID-19 pandemic has reshaped public transportation dynamics globally, prompting shifts in passenger behavior and payment methods. Concurrently, the rise of fintech and Industry 4.0 has accelerated the adoption of digital payment solutions, aligning with the trend towards cashless societies. This study investigates the impact of the pandemic on the transition from cash to card payments for public transport fares in Belo Horizonte, Brazil. Leveraging data from the city's transparency portal, analyses were conducted on passenger numbers, payment methods, and card usage from November 2019 to November 2021. Findings reveal a steady usage of card payments compared to cash, with a notable increase in individual ticket card transactions post-vaccination. Conversely, employer-provided transportation voucher card usage experienced a decline. These trends suggest a preference among users for card-based payments, potentially driven by concerns over direct cash handling and adherence to

Rodrigues, Cádmo, Santos Júnior, Wagner

Campus Bus Station Layout Planning in Mountainous Universities Based on User Needs

13-06-01-0006

12/13/2024

The planning of mountain campus bus routes needs to take into account user demand, convenience, and other factors. This study adopts a comprehensive research method that combines quantitative and qualitative viewpoints. From the perspective of university students, this article studies the demand of campus public transportation and proposes the layout of campus bus routes in mountainous universities to meet the needs of users. The psychological needs questionnaire was used to investigate college students’ expectation of bus station service function. Taking three mountain universities as examples, the integration and selectivity of campus road networks are evaluated by using space syntax analysis, which provides valuable insights into the quality of bus stop areas. This article discusses the correlation between psychological needs assessment of college students and objective conditions of campus road network. The study concludes with the following findings: (1) The pedestrian environment

Duan, Ran, Tang, Rui, Wang, Zhigang, Zhao, Yixue, Wang, Qida, Yang, Jiyi, Su, Jiafu

Technical Paper for 11 ^TH SAE India International Mobility Conference Relevance of Autonomous Vehicles in the Indian Context

2024-28-0122

12/05/2024

Autonomous vehicles (AVs) are positioned to revolutionize transportation, by eliminating human intervention through the use of advanced sensors and algorithms, offering improved safety, efficiency, and convenience. In India, where rapid urbanization and traffic congestion present unique challenges, AVs still hold a significant promise. This technical paper discusses the relevance of autonomous vehicles in the Indian context and the challenges that need to be addressed before the widespread adoption of autonomous vehicles in India. These challenges include the lack of infrastructure, concerns regarding road safety, software vulnerabilities, adaptability of change towards autonomous vehicles, and the management of traffic. The paper also highlights the government's initiatives to encourage the development and adoption of autonomous vehicles, ideology behind the legal framework and the required changes in terms of technological advancements, and urban planning. In a brief manner, this

Mishra, Adarsh, Mathur, Gaurav

Reliability Assessment of Audio Generating Devices- Horn

2024-28-0178

12/05/2024

The increase in vehicular traffic on Indian roads has led to a significant rise in the frequency of horn usage, particularly in city driving conditions and during peak traffic hours. Existing electro-mechanical horns are designed to have a mission life of 100,000 cycles according to Indian standards IS 1884 [1]. However, the intensified usage patterns have prompted a re-evaluation of the efficacy of these requirements. Studies reveal that the average horn blow frequency for normal usage vehicles is approximately three times per kilometer. When extrapolated to various usage categories, such as public transport and privately owned vehicles, observed increase in average horn blowing frequency per kilometer. When extrapolated, this corresponds to more than 4 lakhs cycles for a vehicle mission life of 2.5 lakhs kilometers. This insight drives the need to review and update validation test specifications to better align with customer usage patterns, thereby enhancing component reliability. By

Joshi, Vivek S., Jape, Akshay

Cable Carriers Promote Efficiency in an Autonomous Hospitality Robot

TBMG-52187

12/01/2024

Since the COVID-19 pandemic that advanced contactless service, robots are increasingly being seen conducting routine deliveries around hospitals and hotels. Developed by Robotise Technologies, JEEVES is one such autonomous service robot used in hotels, healthcare facilities, offices, airports, and other settings. Its main duty is to transport materials and products.

Light Airfield Management UAV Based on TurMass Technology

2024-01-7002

11/15/2024

The advent of the low-altitude economy represents a novel economic paradigm that has emerged in recent years in response to technological advancement and an expanding social demand. The low-altitude economy is currently undergoing a period of rapid development, which underscores the importance of ensuring the safety of airfield operations. To enhance operational efficiency, unmanned aerial vehicles (UAVs) can be utilized for the inspection of the surrounding area, runway inspection, environmental monitoring, and other tasks. This paper employs TurMass technology, the TurMass gateway is miniaturised as the communication module of FT24, and the TK8620 development board replaces the LoRa RF module in the ELRS receiver to achieve the communication transmission between the remote control and the receiver. Additionally, a TurMass chip is integrated into the UAV to transmit beacons, while an airfield management aerial vehicle is employed to receive nearby UAV data, thereby preventing

Zhang, Xiaoyang, Chen, Hongming

Hydrogen Fueling Stations for Airports, in Both Gaseous and Liquid Form

AIR8466 (Current)

11/11/2024

The purpose of this AIR is to establish a baseline for hydrogen fueling protocol and process limits for both gaseous and liquid hydrogen fueling of aircraft (eCTOL, eRotor, eVTOL, LTA) at the airport from small aircraft to wide-body. A further goal is to harmonize and establish common aircraft fueling safety definitions wherever possible with other SAE and EUROCAE standards and NFPA codes alike. Hydrogen fueling process limits (including the fuel temperature, the maximum flow rate, time required, etc.) are affected by factors such as ambient temperature, fuel delivery temperature, and initial pressure in the hydrogen storage system. The further goal is to establish basic fueling protocols within these limits as a starting point while evaluating minimum criteria, including evaluation of fueling with or without communications. AIR8466 establishes the protocol and process limits for hydrogen fueling of aircraft and plans to establish fueling protocols starting with small aircraft

AE-5C Aviation Ground Fueling Systems Committee

Airfield Liquid Anti-Icing/Deicing Chemical Applicator to Include Carrier Vehicle

ARP5559 (Current)

10/11/2024

This equipment specification covers requirements for airfield liquid anti-icing/deicing equipment for airfield snow removal purposes. The unit shall include a combination of a carrier vehicle, liquid product tank, and dispensing system. This vehicle as a unit shall be an integrated chemical dispensing deicing/anti-icing application system. Primary application is for the liquid chemical application for cleaning of ice and snow from airfield operational areas such as runways, taxiways, and ramp aprons. The term “carrier vehicle” represents the various self-propelled prime movers that provide the motive power necessary to move snow and ice control equipment during winter operations. The airport operator may require this specified piece of equipment in order to maintain the airfield during large and small snow events. When necessary, the airfield liquid anti-icing/deicing chemical applicator (ALAD) shall be a central and critical element in the winter pavement maintenance fleet in the

G-15 Airport Snow and Ice Control Equipment Committee

Enhancing Availability of Autonomous Shuttle Services: A Conceptual Approach toward Challenges and Opportunities

12-08-03-0023

10/09/2024

Autonomous vehicle technologies have become increasingly popular over the last few years. One of their most important application is autonomous shuttle buses that could radically change public transport systems. In order to enhance the availability of shuttle service, this article outlines a series of interconnected challenges and innovative solutions to optimize the operation of autonomous shuttles based on the experience within the Shuttle Modellregion Oberfranken (SMO) project. The shuttle shall be able to work in every weather condition, including the robustness of the perception algorithm. Besides, the shuttle shall react to environmental changes, interact with other traffic participants, and ensure comfortable travel for passengers and awareness of VRUs. These challenging situations shall be solved alone or with a teleoperator’s help. Our analysis considers the basic sense–plan–act architecture for autonomous driving. Critical components like object detection, pedestrian tracking

Dehghani, Ali, Salaar, Hamza, Srinivasan, Shanmuga Priya, Zhou, Lixian, Arbeiter, Georg, Lindner, Alisa, Patino-Studencki, Lucila

Micromobility and the Next Infrastructure Wave

EPR2024022

10/04/2024

US transportation infrastructure is dominated by the automobile form factor. Alternative modalities of movement, such as bikes, golf carts, and other micromobility options, have existed but are decidedly at a lower tier of importance. Even pedestrian access ways are not overly emphasized in the US transportation system. This lack of prioritization matches the reality that the vast majority of people and commerce moves through the motor vehicle infrastructure, with micromobility sitting in the periphery. Additionally, given the current lack of commercial applications, there are limited direct fee-based funding mechanisms connected to micromobility form factors. Micromobility and the Next Infrastructure Wave discusses how recent technological innovations in electrification, e-commerce, and autonomy are enabling a new class of micromobility devices which offer palpable value to consumers and enable significant commercial applications. Unlike the past, these micromobility devices now have

Razdan, Rahul

Efficient GPS Route Matching Method for Battery Electric Bus Fleets

2024-24-0026

09/18/2024

A challenge of public transportation GPS data is the frequent utilization of monitoring systems with low sampling rates, primarily driven by the high costs associated with cellular data transmission of large datasets. Altitude data is often imprecise or not recorded at all in regions without large elevation changes. The low data quality limits the use of the data for further detailed investigations like a realistic energy consumption forecast for assessing the electrical grid load resulting from charging the vehicle fleet. Modern research often reconstructs speed data only, or uses additional GPS loggers, which is associated with increased costs in the vehicle fleet. The importance of precise and high-quality altitude data and specialized expertise in mountainous regions are frequently overlooked. This paper introduces an efficient new route matching method to reconstruct speed and respective road slope data of a GPS signal sampled at low frequency for a public transportation electric

Hitz, Arne, Konzept, Anja, Reick, Benedikt, Rheinberger, Klaus

Evaluation of Friction Torque in Tapered Roller Bearings

2024-01-3047

09/08/2024

A bearing is a mechanical component that transmits rotation and supports load. Depending on the type of rotating mechanism, bearings are categorized into ball bearings and tapered-roller bearings. Tapered-roller bearings are superior to ball bearings in load-bearing capabilities. They are used in applications where high loads, such as, the wheel bearings for commercial vehicles and trucks, aircraft, high-speed trains, and heavy-duty spindles for heavy machinery must be supported. The demand for reducing the friction torque in automobiles has recently increased owing to carbon-emission regulations and fuel-efficiency requirements. Therefore, research on the friction torque of bearings is essential; studies have been conducted on lubrication, friction, and contact in tapered-roller bearings. There have also been studies on lip friction, roller misalignment, and so on; however, research on the influence of roller geometries and material properties is scarce. This study investigated the

Lee, Seungpyo, An, Hyun Gyu

Exploration of the Impact of Built Environment Factors on Morning and Evening Peak Ridership at Urban Rail Transit Stations: A Case Study of Changsha, China

13-06-02-0009

07/22/2024

To identify the influences of various built environment factors on ridership at urban rail transit stations, a case study was conducted on the Changsha Metro. First, spatial and temporal distributions of the station-level AM peak and PM peak boarding ridership are analyzed. The Moran’s I test indicates that both of them show significant spatial correlations. Then, the pedestrian catchment area of each metro station is delineated using the Thiessen polygon method with an 800-m radius. The built environment factors within each pedestrian catchment area, involving population and employment, land use, accessibility, and station attributes, are collected. Finally, the mixed geographically weighted regression models are constructed to quantitatively identify the effects of these built environment factors on the AM and PM peak ridership, respectively. The estimation results indicate that population density and employment density have significant but opposite influences on the AM and PM peak

Su, Meiling, Liu, Ling, Chen, Xiyang, Long, Rongxian, Liu, Chenhui

Environment-Adaptive Localization based on GNSS, Odometry and LiDAR Systems

2024-01-2986

07/02/2024

In the evolving landscape of automated driving systems, the critical role of vehicle localization within the autonomous driving stack is increasingly evident. Traditional reliance on Global Navigation Satellite Systems (GNSS) proves to be inadequate, especially in urban areas where signal obstruction and multipath effects degrade accuracy. Addressing this challenge, this paper details the enhancement of a localization system for autonomous public transport vehicles, focusing on mitigating GNSS errors through the integration of a LiDAR sensor. The approach involves creating a 3D map using the factor graph-based LIO-SAM algorithm, which is further enhanced through the integration of wheel encoder and altitude data. Based on the generated map a LiDAR localization algorithm is used to determine the pose of the vehicle. The FAST-LIO based localization algorithm is enhanced by integrating relative LiDAR Odometry estimates and by using a simple yet effective delay compensation method to

Kramer, Markus, Beierlein, Georg

Configuration and Design of Mobile Checkout System for Ground Testing of Reusable Launch Vehicle

2024-26-0454

06/01/2024

The winged body reusable launch vehicle needs to be tested and evaluated for its functionality during the pre-flight preparation at the runway. The ground based checkout systems for the avionics and the actuator performance testing during pre-flight evaluation are not designed for rapid movement. This new kind of launch vehicle with solid rocket first-stage and winged body upper-stage demands the system testing at Launchpad and at the runway. The safety protocol forbids the permanent structure for hosting the checkout system near runway. The alternative is to develop a rapidly deployable and removable checkout system. A design methodology adopting conventional industrial instrumentation systems and maintaining mobility is presented. This paper presents the design and development of a mobile checkout system for supporting the ground pre-flight testing during autonomous flight landing trials.

V, Vivekanand

FEA Stress Determination for Weld Fatigue using Hot-Spot Stress Method: Benchmarking and Rail Application

SAE-PP-0039405/05/2024

Welded joints in rail steel structures are typically assessed for fatigue using two different stress range approaches: nominal stress range and hot-spot stress range when using SN methods. The nominal stress range is a traditionally simplified method that provides a conservative estimation but lacks accuracy in considering stress concentrations. On the other hand, the hot-spot stress range method is a more advanced and refined approach that offers a more precise evaluation of stress concentration, making it suitable for complex geometries. In 2015, the British standard BS7608-2015 on Guide to Fatigue Design and Assessment of Steel Products incorporated the hot-spot method for evaluating weld joints, especially when using numerical methods as Finite Element Analysis (FEA). The weld classes are now categorically defined for both nominal and hot-spot approaches in new introductions, whereas earlier, it was based on the nominal stress approach only. Choosing the appropriate stress range

Patil, Dipak

Transportation Ecosystem and Autonomy: Vol. 3

EPRCOMPV212023

05/03/2024

The impending deployment of automated vehicles (AVs) represents a major shift in the traditional approach to ground transportation; its effects will inevitably be felt by parties directly involved with vehicle manufacturing and use (e.g., automotive original equipment manufacturers (OEMs), public transportation systems, heavy goods transportation providers) and those that play roles in the mobility ecosystem (e.g., aftermarket and maintenance industries, infrastructure and planning organizations, automotive insurance providers, marketers, telecommunication companies). The focus of this chapter is to address a topic overlooked by many who choose to view automated driving systems and AVs from a “10,000-foot perspective:” the topic of how AVs will communicate with other road users such as conventional (human-driven) vehicles, bicyclists, and pedestrians while in operation. This unsettled issue requires assessing the spectrum of existing modes of communication—both implicit and explicit

Beiker, Sven, Razdan, Rahul, Favaro, Francesca, Taiber, Joachim, Sell, Raivo

The New Future of Public Transportation

R-56904/11/2024

Discover the highly anticipated Second Edition to the Amazon #1 Best Seller, The Future of Public Transportation. Delve into 30 expertly crafted chapters brimming with insights from leading public transportation figures. From hydrogen-fueled buses to AI-driven advancements and cybersecurity, this book offers an unparalleled glimpse into the future of transit. Navigate the complexities of transit planning in a post-COVID world, where innovative solutions are essential to tackle infrastructure challenges and workforce shortages. Learn how AI is revolutionizing transit planning, enhancing outcomes for riders. Explore cutting-edge transit technology, including autonomous vehicles and zero-emission initiatives, with a focus on sustainability and customer experience. Whether you're a seasoned professional or new to the field, this book is your roadmap to success, empowering you to drive positive change in your organization. Join us on the journey towards a more efficient, sustainable, and

Comfort, Paul

Influence of Working Conditions and Operating Parameters on the Energy Consumption of a Full-Electric Bus. Experimental Assessment

2024-01-2174

04/09/2024

Given the growing interest in improving the efficiency of the bus fleet in public transportation systems, this paper presents an analysis of the energy consumption of a battery electric bus. During the experimental campaign, a battery electric bus was loaded using sand payloads to simulate the passenger load on board and followed another bus during regular service. Data related to the energy consumed by various bus utilities were published on the vehicle’s CAN network using the FMS standard and sampled at a frequency of 1 Hz. The collected experimental data were initially analyzed on a daily basis and then on a per-route basis. The results reveal the breakdown of energy consumption among various utilities over the course of each day of the experiment, highlighting those responsible for the highest energy consumption. Subsequently, the relationship between the energy consumption of the traction motor and the climate control system was investigated concerning environmental parameters

Belloni, Mattia, Tarsitano, Davide, Sabbioni, Edoardo

Study on Aircraft Wing Collision Avoidance through Vision-Based Trajectory Prediction

2024-01-2310

04/09/2024

When the aircraft towing operations are carried out in narrow areas such as the hangars or parking aprons, it has a high safety risk for aircraft that the wingtips may collide with the surrounding aircraft or the airport facility. A real-time trajectory prediction method for the towbarless aircraft taxiing system (TLATS) is proposed to evaluate the collision risk based on image recognition. The Yolov7 module is utilized to detect objects and extract the corresponding features. By obtaining information about the configuration of the airplane wing and obstacles in a narrow region, a Long Short-Term Memory (LSTM) encoder-decoder model is utilized to predict future motion trends. In addition, a video dataset containing the motions of various airplane wings in real traction scenarios is constructed for training and testing. Compared with the conventional methods, the proposed method combines image recognition and trajectory prediction methods to describe the relative positional relationship

Zhu, Hengjia, Xu, Yitong, Xu, ZiShuo, JiYuan, Liu, Zhang, Wei

Efficient Electric School Bus Operations: Simulation-Based Auxiliary Load Analysis

2024-01-2404

04/09/2024

The study emphasizes transitioning school buses from diesel to electric to mitigate their environmental impact, addressing challenges like limited driving range through predictive models. This research introduces a comprehensive control-oriented model for estimating auxiliary loads in electric school buses. It begins by developing a transient thermal model capturing cabin behavior, divided into passenger and driver zones. Integrated with a control-oriented HVAC model, it estimates heating and cooling loads for desired cabin temperatures under various conditions. Real-world operational data from school bus specifications enhance the model’s practicality. The models are calibrated using experimental cabin-HVAC data, resulting in a remarkable overall Root Mean Square Error (RMSE) of 2.35°C and 1.88°C between experimental and simulated cabin temperatures. A lateral powertrain model has been developed that encompasses vehicle dynamics, electric machinery, transmission, and electrical loads

Nawaz, Muneebullah, Alsharif, Khaled, Hanif, Athar, Ahmed, Qadeer

LED Landing, Taxiing, Runway Turnoff, and Recognition Lights

ARP6402B (Current)

03/22/2024

This document includes recommendations of installations of adequate landing and taxiing lighting systems in aircraft of the following categories: a Single engine personal and/or liaison type b Light twin engine c Large multiengine propeller d Large multiengine turbojet e Military high-performance fighter and attack f Helicopter g Electric Vertical Takeoff and Landing (EVTOL) and Urban Air Mobility (UAM)

A-20B Exterior Lighting Committee

Liquid Runway Deicing/Anti-icing Product

AMS1435E (Current)

03/12/2024

This specification covers runway deicing and anti-icing products in the form of a liquid. Unless otherwise stated, all specifications referenced herein are latest (current) revision.

G-12RDP Runway Deicing Product Committee

Solid Runway Deicing/Anti-icing Product

AMS1431F (Current)

03/12/2024

This specification covers a runway deicing and anti-icing product in the form of a solid. Unless otherwise stated, all specifications referenced herein are latest (current) revision.

G-12RDP Runway Deicing Product Committee

Weld Fatigue Damage Assessment of Rail Track Maintenance Equipment: Regulatory Compliance and Practical Insights

05-17-02-0010

03/04/2024

The use of appropriate loads and regulations is of great importance in weld fatigue assessment of rail on-track maintenance equipment and similar vehicles for optimized design. The regulations and available loads, however, are often generalized for several categories, which proves to be overly conservative for some specific categories of machines. EN (European Norm) and AAR (Association of American Railroads) regulations play a pivotal role in determining the applicable loads and acceptance criteria within this study. The availability of track-induced fatigue load data for the cumulative damage approach in track maintenance machines is often limited. Consequently, the FEA-based validation of rail track maintenance equipment often resorts to the infinite life approach rather than cumulative damage approach for track-induced travel loads, resulting in overly conservative designs. The work presented in this article evaluates and compares the weld fatigue damage of track maintenance

Patil, Dipak, Petersen, Michael

The Scope of Autonomous Vehicle Mobility with an Indian Context

2024-26-0087

01/16/2024

The advent of autonomous vehicles promises to revolutionize the transportation sector globally, and India, as one of the world's fastest-growing economies, stands at the forefront of this transformative technology. This paper presents a brief overview of the current state and potential implications of autonomous vehicles in the Indian context. With its densely populated cities, diverse traffic conditions, and complex road infrastructure, India presents unique challenges and opportunities for the deployment of autonomous vehicles. This technology has the potential to address critical issues such as road safety, congestion, and pollution while transforming the mobility experience for millions of people. However, several hurdles must be overcome to fully harness its benefits. The paper explores key considerations for the implementation of autonomous vehicles in India. These include adapting the technology to navigate chaotic traffic scenarios, addressing infrastructure limitations, and

Shetty, Sharan Harish

A Smart Transportation System for Existing Vehicles and Roads Infrastructure to Ease Traffic and Toll Problems in India

2024-26-0181

01/16/2024

India is a highly populous country. The traffic problems faced by the people here are not uncommon. The increase in traffic leads to increase in accidents, pollution, inconvenience and frustration. It also comes with costs of additional fuel and time. Though public transport is extensively available in India, still it isn't sufficient for the population of India. Especially in Metro cities, public transport services are often crowded. So, to travel peacefully people are opting for commuting in their own vehicles. And as a result, more vehicles are coming on roads. Other major reasons for increasing traffic are lack of proper implementation of traffic rules and traffic signals out of sync. In addition to city traffic, congestion is also seen on highways, mainly at toll plazas. Although implementation of FASTag has reduced it to some extent, some toll plazas still face traffic congestion issues. This paper provides an idea to ease the traffic problems in the city and on the highways too

Jain, Pritesh

Twin Motor System for Electric Vehicle Propulsionby by Means of Energy Source

2024-26-0113

01/16/2024

The transport sector in all domains like personal vehicles, public transport and logistics has seen a tremendous growth over the past decade, more so in the last 5 years. The main reasons for this rapid growth is the development of new energy storage systems in battery technology (Lithiumion, sodium ion, aluminum air etc.), hydrogen fuel cells, super capacitors etc. On the other hand there has been tremendous development in the motor drive technology with the availability of brushless dc motors (BLDC Motors), induction motors, Permanent magnet synchronous motors (PMSM, IPMSM). Each motor having its own special characteristics and usage suited for a very specific application in terms of torque and load bearing capacities. In this paper we describe a unique platform with twin motor drive system electric vehicle which is powered by an artificial intelligence (AI) enabled electronic module DuoPackR. The basic platform is described with the help of a bicycle which has two BLDC motors on the

Pratiwadibhayankaram, Ashwini Kumar Krishnaswamy, K A, Rakesh, Sangam, Manjunath

Automated Charging Methodology for Fleet Operated EV Buses to Reduce Down Time and Increase Safety at Charging Station

2024-26-0112

01/16/2024

Prime concern for electric vehicle where the application of the vehicle is public transport, is the charging of vehicle and operation of its infrastructure. Such an example of operating the EV buses is under the GCC (gross cost contract) model, with high operation time and comparatively lesser time for charging. It is challenging to meet these requirements. To counter this situation in fleet operated busses it is proposed to adapt an automated charging method which involves minimum man power intervention and automated mechanism to connect & disconnect the charging connectors. This paper proposes an automated pantograph mechanism based method of charging EV buses, meeting requirements as per SAE J3105 & ISO 15118 standards, which would be an ideal way to resolve the current situation. In the above mentioned pantograph type charging, the charging station or depot will have an infrastructure including charger whose input will be from grid, and the charging dispenser will be pantographs

Gullyal, Avinash, Ahmed, Yasir, Amancharla, Naga Chaithanya, Kinjalkar, Milind

Simulation Methodology Development for Vibration Test of Bus Body Structure Code AIS-153:2018

2024-26-0249

01/16/2024

A bus is integral part of public transportation in both rural and urban areas. It is also used for scheduled transport, tourism, and school transport. Buses are the common mode of transport all over the world. The growth in economy, the electrification of public transport, demand in shared transport, etc., is leading to a surge in the demand for buses and accelerating the overall growth of the bus industry. With the increased number of buses, the issue of safety of passengers and the crew assumes special importance. The comfort of driver and passenger in the vehicle involves the vibration performance and therefore, the structural integrity of buses is critically important. Bus safety act depicts the safety and comfort of bus operations, management of safety risks, continuous improvement in bus safety management, public confidence in the safety of bus transport, appropriate stakeholder involvement and the existence of a safety culture among bus service providers. In order to provide

Bijwe, Vilas B., Mahajan, Rahul, Vaidya, Rohit, Patel, Kaustubh, Hiwale, Diwakar, Walke, Abhijit Ashok

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