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Advanced Driver-Assistance Systems for City Bus Applications

Kowloon Motor Bus Co.-Chun Yi Lo
Queen's University Belfast-Luke Blades, Roy Douglas, Juliana Early
  • Technical Paper
  • 2020-01-1208
To be published on 2020-04-14 by SAE International in United States
In 2018 there were over 1,700 fatalities on Great Britain roads, with over 25,000 people seriously injured. With vehicle miles increasing each year it is important that there is improved on-road safety, both for passenger cars and for public transport. Nowadays, advanced driver-assistance systems (ADAS) are widely utilized, with the EU Commission mandating ADAS such as autonomous emergency braking (AEB), lane-keeping assistance and reversing cameras on all new cars from 2021. Transport for London have introduced the Bus Safety Standard, within which is the requirement for ADAS systems, many of which are due to become mandatory from 2021. This study uses statistical analysis of bus accidents that have occurred across Great Britain in order to determine which ADAS technologies may result in the largest reduction of potential bus accidents. It discusses the technologies available for bus applications and compares those that are appropriate with those utilized on cars. Police reported traffic accident data for Great Britain, over the period 2011-2017, was filtered down to over 30,000 injuries caused by accidents involving buses. From this data…
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Variability of driving conditions and its effect on charging time for urban battery electric buses

University of Michigan-Anshul Paunikar, Rasoul Salehi
  • Technical Paper
  • 2020-01-0598
To be published on 2020-04-14 by SAE International in United States
Due to growing environmental concerns and stringent vehicle emissions regulations, there is a constant urge in the automotive industry to move towards electrified propulsion systems. Public transportation plays a major role in contributing towards lowering the emission level. Battery electric buses are regarded as a type of promising green mass transportation as they provide the advantage of less greenhouse gas emissions per passenger. However, the electric bus poses a threat of limited range and is not able to drive throughout the day without being charged again. This research focuses on the current bus transit systems in the city of Ann Arbor and investigates the impact of different electrification levels on the final CO2 reduction. Utilizing models of a conventional diesel bus, hybrid electric bus, and battery electric bus, the CO2 emission for each type of transportation bus is estimated. Measured vehicle speed data from various routes under different driving conditions are used to investigate the variability of performance metrics. Finally, recommendations are made for charge requirements of battery electric bus considering the variation in drive…
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Optimal Control of Mass-transport Time-delay Model in a Low-pressure EGR

GIPSA-lab-Emmanuel Witrant
Grenoble INP-Didier Georges
  • Technical Paper
  • 2020-01-0251
To be published on 2020-04-14 by SAE International in United States
This paper presents the control-oriented model and control design of the burned gas ratio(BGR) transport phenomenon, witnessed in the intake path of an internal combustion engine, due to the redirection of burned gases to the intake path by the low-pressure EGR. Based on a nonlinear AMESim model of the engine, the BGR in the intake manifold is modeled as a state-space output time-delay model, or alternatively as an ODE-PDE coupled system, that take into account the time delay between the moment at which the combusted gases leave the exhaust manifold and that at which they are readmitted in the intake manifold. In addition to their mass transport delay, the BGRs in the intake path are also subject to inequality constraints because they are positive percentages lying between 0 and 100. The objective of the control problem is to track a reference output profile of the BGR in the intake manifold, taking into account the transport delay and the state(output) and input constraints of the system. In this aim, two indirect optimal control approaches are implemented…
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Unsettled Impacts of Integrating Automated Electric Vehicles into a Mobility-as-a-Service Ecosystem and Effects on Traditional Transportation and Ownership

International Transportation Innovation Center (ITIC)-Joachim Taiber
Tallinn University of Technology-Raivo Sell
  • Research Report
  • EPR2019004
Published 2019-12-20 by SAE International in United States
The current business model of the automotive industry is based on individual car ownership, yet new ridesharing companies such as Uber and Lyft are well capitalized to invest in large, commercially operated, on-demand mobility service vehicle fleets. Car manufacturers like Tesla want to incorporate personal car owners into part-time fleet operation by utilizing the company’s fleet service. These robotaxi fleets can be operated profitably when the technology works in a reliable manner and regulators allow driverless operation.Although Mobility-as-a-Service (MaaS) models of private and commercial vehicle fleets can complement public transportation models, they may contribute to lower public transportation ridership and thus higher subsidies per ride. This can lead to inefficiencies in the utilization of existing public transportation infrastructure. MaaS platforms can also cause a reduced reliance on parking infrastructure (e.g., street parking lanes and parking garages) which can contribute to an improvement in overall traffic flow, and a reduction in capital investment for commercial and residential real-estate development. Urban planning can be better centered around the true mobility needs of the citizens without sacrificing valuable…
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Precipitation Study of B30 Blended from FAME and/or HVO and Petro Diesel Fuel

Agency for Assessment and Application of Technology Kawasan-Hari Setiapraja, Imam Paryanto
Department of Chemical Engineering, Faculty of Engineering,-Misri Gozan
  • Technical Paper
  • 2019-01-2190
Published 2019-12-19 by SAE International in United States
Indonesia has planned for the implementation of B30 fuel in 2020, and as a consequence, a large-scale production of biodiesel from palm oil will be significantly increased in the country. In application as public transportation fuel, biodiesel quality and blending composition play an important role for the success of the implementation of B30 program. Indonesia consists of highlands and lowlands as urban areas that have different temperature regions varying from 12 - 35°C. Cold temperature could accelerate the formation of precipitate of B30 fuels. Samples of B30 fuels were made by blending biodiesel and/or hydrogenated vegetable oil (HVO) with Euro 3 and Euro 4 petro diesel fuels. The precipitate composed of monoglycerol and FAME. Precipitation of the chemicals was caused by their higher melting point that crystallized and the solvency effect of petro diesel in cold temperature. It was found that the amount of precipitate formed in B30 blended from 30% FAME and 70% Euro 4 petro diesel fuel was the highest one. Therefore, the requirement for monoglycerol and moisture contents in biodiesel quality needed…
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Windshield Glare from Bus Interiors: Potential Impact on City Transit Drivers at Night

SAE International Journal of Transportation Safety

OSHTECH Incorporated, Canada-Peter Pityn, Sue Clouse-Jensen
  • Journal Article
  • 09-07-02-0008
Published 2019-11-15 by SAE International in United States
Windshield glare at night is a safety concern for all drivers. Public transit bus drivers also face another concern about glare caused by interior lighting sources originally designed for passenger safety. The extent to which interior light reflections contribute to glare is unknown. Unique methods for measuring discomfort and disability glare during bus driving were developed. An initial simulation study measured windshield luminance inside of a New Flyer D40LF diesel bus parked in a controlled, artificial, totally darkened test environment. Findings indicated significant disability glare (from elevated luminance) in the drivers’ primary field of view due to interior reflections. Any reduction in contrast would result in less prominent glare if actual driving conditions differ. To assess this, levels of windshield glare were also measured with the bus parked on the roadside under the “background glow” of the urban environment. Findings reveal that under road conditions the extent of disability glare from interior reflections is much less, but not negligible, when contrast is reduced. The information gathered in these studies may be useful to manufacturers and…
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Transformational Technologies Reshaping Transportation - An Academia Perspective

Ohio State University-Giorgio Rizzoni, Qadeer Ahmed, Mukilan Arasu, Pradeep Sharma Oruganti
Published 2019-10-14 by SAE International in United States
This paper and the associated lecture present an overview of technology trends and of market and business opportunities created by technology, as well as of the challenges posed by environmental and economic considerations. Commercial vehicles are one of the engines of our economy. Moving goods and people efficiently and economically is a key to continued industrial development and to strong employment. Trucks are responsible for nearly 70% of the movement of goods in the USA (by value) and represent approximately 300 billion of the 3.21 trillion annual vehicle miles travelled by all vehicles in the USA while public transit enables mobility and access to jobs for millions of people, with over 10 billion trips annually in the USA creating and sustaining employment opportunities.Commercial vehicles provide access to work and leisure time for millions of people every day and deliver and distribute the goods that make our economy move, from raw materials, to components, to finish products, as well as providing a multitude of services and support functions. While on-road trucks and buses represent only part…
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Prediction of Hydraulic Cavitation Using 1D Simulation

John Deere India Pvt. Ltd.-Vinit Jawale, Ameya Bandekar
VJTI-Pritam Shinde, Addanki Rao
Published 2019-10-11 by SAE International in United States
Hydraulic Cavitation is, in many cases, an undesirable occurrence. It is the formation and collapse of air cavities in liquid. In hydraulic devices such as pumps, motors, etc. cavitation causes a great deal of noise, local erosion, damage to components, vibrations, increases oil contamination and a loss of efficiency. There is already established process of predicting cavitation using 3D simulation software. However, the model development is the time-consuming process as well as prediction process is component /subsystem level and cannot be done for various duty cycle operations at architecture level. That requires exploring our research in 1D simulation technique for prediction of cavitation. In this research, we have developed and implemented a methodology/mathematical model for the prediction of hydraulic cavitation in hydraulic system using a 1D simulation technique. For simulation purpose, we have taken an example of simple hydraulic system and predicted the cavitation in one of the component/subsystem of hydraulic system for ambient conditions. The mathematical model proposed based on mass transport equations of vapor, liquid and gas, Rayleigh-Plesset equations, Singhal model and bubble…
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ZF's Tech Portfolio is Ready for Level 4 Autonomy

Autonomous Vehicle Engineering: September 2019

Stuart Birch
  • Magazine Article
  • 19AVEP09_11
Published 2019-09-01 by SAE International in United States

Well aware of the relentless hype that comes with automated driving development, ZF's autonomy boss knows cost will be crucial-and customer persuasion required.

“We are constantly asking this question: Who is the customer likely to buy an SAE Level 4 autonomous vehicle in the consumer passenger market?” This is one of the key queries that drives the thinking of Torsten Gollewski, head of autonomous mobility systems at ZF. The global Tier 1 is playing a crucial role in enabling the next generation of mobility.

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Comparison of GATS Messages to SAE ATIS Standards

V2X Core Technical Committee
  • Ground Vehicle Standard
  • J2539_201906
  • Current
Published 2019-06-11 by SAE International in United States
This SAE Information Report provides a comparative summary between the various messages found in the SAE ATIS standards work (notably SAE J2313, J2353, J2354, J2369 and J2374) and that found in the GATS standard (Global Automotive Telematics Standard). GATS is a message set meant to be deployed on mobile phone systems based on the GSM (Global System for Mobile Communication) phone system which is being deployed in European markets and which the SAE may need to harmonize with as part of the World Standards activities of TC204. This document provides an overview of the various types of supported messages and how they compare with US terms and messages. Some selected features of the GATS work are recommended for assimilation into the next revision of ATIS standards. No attempt at determining a U.S. policy in this regard is provided. This document seeks to provide the reader familiar with SAE ATIS with a high level overview of technical knowledge of the GATS approach in similar areas.
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