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Unsettled Technology Areas In Electric Propulsion Systems
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Book Synopsis Unsettled Technology Areas in Electric Propulsion Systems by : Yuxiang Jiang
Download or read book Unsettled Technology Areas in Electric Propulsion Systems written by Yuxiang Jiang and published by SAE International. This book was released on 2021-05-24 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electric vehicle (EV) transmission technology—crucial for battery electric vehicles (BEVs) and hybrid electric vehicles (HEVs)—is developing quickly and customers want good performance at a low cost. Single-speed gearboxes are popular in electric drive systems due to their simple and cost-effective configuration. However, multispeed gearboxes are being taken to market due to their higher low-speed torque, dynamic performance, and energy efficiency. Unsettled Technology Areas in Electric Propulsion Systems reviews the economic drivers, existing techniques, and current challenges of EV transmission technology—including torque interruption during shifting; thermal and sealing issues; and noise, vibration, and harshness (NVH). This report discusses the pros and cons for both single-speed and multispeed gearboxes with numerical analysis. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2021012
Book Synopsis Unsettled Domains Concerning Electric Propulsion Technology for Commercial Aircraft by : Ravi Rajamani
Download or read book Unsettled Domains Concerning Electric Propulsion Technology for Commercial Aircraft written by Ravi Rajamani and published by SAE International. This book was released on 2019-12-30 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: According to some, electric propulsion is already on its way down the “trough of disillusionment.” This report argues that while there are some concerns with associated technologies, such pessimism is unwarranted. Yes, battery systems can be more energy dense; charging standards are late in being developed; it is not clear what technologies and architectures will win out for which sectors; we still have to figure out how to deal with thermal management issues at all levels in future designs; and what might be the certification standards for electric aircraft. But that does not mean that these issues will not be addressed. Yes, these unsettled questions may take a little longer to solve than originally estimated, but there is full expectation within the industry that electric propulsion for commercial aircraft will succeed. In this SAE EDGE Research Report we present points of view from leading researchers in the industry who are thinking deeply about solving these problems. NOTE: SAE EDGE™ Research Reports are intended to identify and illuminate key issues in emerging, but still unsettled, technologies of interest to the mobility industry. The goal of SAE EDGE™ Research Reports is to stimulate discussion and work in the hope of promoting and speeding resolution of identified issues. SAE EDGE™ Research Reports are not intended to resolve the issues they identify or close any topic to further scrutiny. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2019006
Book Synopsis Key Technology Challenges of Electric Ducted Fan Propulsion Systems for eVTOL by : Yuping Qian
Download or read book Key Technology Challenges of Electric Ducted Fan Propulsion Systems for eVTOL written by Yuping Qian and published by SAE International. This book was released on 2023-11-22 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electrical vertical takeoff and landing (eVTOL) vehicles for urban air mobility (UAM) are garnering increased attention from both the automotive and aerospace industries, with use cases ranging from individual transportation, public service, cargo delivery, and more. Distributed electric propulsion systems are their main technical feature; they determine vehicle size and propulsion efficiency and provide distributed thrust to achieve attitude control. Considering the intended role of eVTOL vehicles, ducted-fan systems are ideal choice for the propulsor, as the duct provides a physical barrier between the rotating blades and the human, especially during the take-off and landing phases. Key Technology Challenges of Electric Ducted Fan Propulsion Systems for eVTOL introduces the main bottlenecks and key enablers of ducted-fan propulsion systems for eVTOL applications. Based on the introduction and discussion of these important issues, this report will help eVTOL engineers understand the key technical issues and inspire them to develop the ideal solutions that will enable eVTOL vehicle deployment for UAM operations. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2023027
Book Synopsis Unsettled Issues Regarding the Certification of Electric Aircraft by : Ravi Rajamani
Download or read book Unsettled Issues Regarding the Certification of Electric Aircraft written by Ravi Rajamani and published by SAE International. This book was released on 2021-03-26 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aerospace industry is beginning to grapple with the reality of certifying electric aircraft (EA), signaling the maturing of the field. Many players are ramping up their activities to respond to imminent technical, safety, and regulatory requirements. While there are gaps in EA knowledge as well as the processes for certifying them, some leading standards development organizations (SDOs) such as SAE International, ASTM International, and RTCA—ably supported by representatives from regulatory agencies—are stepping in to address many of these issues. Of special importance are the new rule changes in the normal category (14 CFR Part 23, Amendment 64) that shift from a prescriptive philosophy to “performance-based rules.” Regarding system knowledge, there has been a trend in the use electrical energy to power systems that have long employed mechanical hydraulics. In the new EA paradigm, these components will be employed at criticality levels not previously witnessed in conventional aircraft, calling for a specific set of certification demands. Unsettled Issues Regarding the Certification of Electric Aircraft tackles the certification challenges faced by EA manufacturers in both the small (normal) and large (transport) categories, addressing technical, business, and process issues. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2021007
Book Synopsis The Role of Hybrid Vehicles in a Net-zero Transport System by : Jody Emlyn Muelaner
Download or read book The Role of Hybrid Vehicles in a Net-zero Transport System written by Jody Emlyn Muelaner and published by SAE International. This book was released on 2024-09-25 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the world looks to net-zero emissions goals, hybrid electric vehicles may play an increasingly important role. For passenger electric vehicles (EVs) that predominantly make short journeys but occasionally need to make longer trips, electrofuel range extension may be more cost effective than either hydrogen or rapid charging. Micro gas turbines and catalytic combustion show significant potential to deliver low-cost, low-maintenance, lightweight engines with virtually no emissions, and hydrocarbon consuming solid oxide fuel cells show even greater potential in these areas. Aditioanlly, sodium-ion batteries for EVs, dispatachable vehicle-to-grid power and buffering, and variable intermittent renewable energy could also play key roles. The Role of Hybrid Vehicles in a Net-zero Transport System explores the costs, considerations, and challenges facing these technologies. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2024021
Book Synopsis Electric Road Systems for Dynamic Charging by : Jody Emlyn Muelaner
Download or read book Electric Road Systems for Dynamic Charging written by Jody Emlyn Muelaner and published by SAE International. This book was released on 2022-03-11 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electric road systems (ERS) enable dynamic charging—the most energy efficient and economical way to decarbonize road vehicles. ERS draw electrical power directly from the grid and enable vehicles with small batteries to operate without the need to stop for charging. The three main technologies (i.e., overhead catenary lines, road-bound conductive tracks, and inductive wireless systems in the road surface) are all technically proven; however, no highway system has been commercialized. Electric Road Systems for Dynamic Charging discusses the technical and economic advantages of dynamic charging and questions the current investment in battery-powered and hydrogen-fueled vehicles. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2022007
Book Synopsis Unsettled (Updated and Expanded Edition) by : Steven E. Koonin
Download or read book Unsettled (Updated and Expanded Edition) written by Steven E. Koonin and published by BenBella Books. This book was released on 2024-06-11 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this updated and expanded edition of climate scientist Steven Koonin’s groundbreaking book, go behind the headlines to discover the latest eye-opening data about climate change—with unbiased facts and realistic steps for the future. "Greenland’s ice loss is accelerating." "Extreme temperatures are causing more fatalities." "Rapid 'climate action' is essential to avoid a future climate disaster." You've heard all this presented as fact. But according to science, all of these statements are profoundly misleading. With the new edition of Unsettled, Steven Koonin draws on decades of experience—including as a top science advisor to the Obama administration—to clear away the fog and explain what science really says (and doesn't say). With a new introduction, this edition now features reflections on an additional three years of eye-opening data, alternatives to unrealistic “net zero” solutions, global energy inequalities, and the energy crisis arising from the war in Ukraine. When it comes to climate change, the media, politicians, and other prominent voices have declared that “the science is settled.” In reality, the climate is changing, but the why and how aren’t as clear as you’ve probably been led to believe. Koonin takes readers behind the headlines, dispels popular myths, and unveils little-known truths: Despite rising greenhouse gas emissions, global temperatures decreased from 1940 to 1970 Models currently used to predict the future do not accurately describe the climate of the past, and modelers themselves strongly doubt their regional predictions There is no compelling evidence that hurricanes are becoming more frequent—or that predictions of rapid sea level rise have any validity Unsettled is a reality check buoyed by hope, offering the truth about climate science—what we know, what we don’t, and what it all means for our future.
Book Synopsis Unsettled Topics in Unmanned Aerial Vehicle Icing by : Richard Hann
Download or read book Unsettled Topics in Unmanned Aerial Vehicle Icing written by Richard Hann and published by SAE International. This book was released on 2020-04-27 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unmanned aerial vehicles (UAVs) are an emerging technology with a large variety of commercial and military applications. In-flight icing occurs during flight in supercooled clouds or freezing precipitation and is a potential hazard to all aircraft. In-flight icing on UAVs imposes a major limitation on the operational envelope. This report describes the unsettled topics related to UAV icing. First, typical UAV applications and the general hazards of icing are described. Second, an overview of the special technical characteristics of icing on autonomous and unmanned aircraft is given. Third, the operational challenges for flight in icing conditions are discussed. Fourth, technologies for ice protection that mitigate the icing hazard are introduced. Fifth, the tools and methods required to understand UAV icing and to develop aircraft with cold-weather capabilities are presented. Finally, an assessment of the current and future regulations regarding icing on UAVs is provided. Icing is a key challenge that the UAV industry needs to address in order to unlock the full potential of this emerging technology. UAVs must be capable of safe and reliable operation in a wide range of weather conditions. This report outlines the most important challenges and gives short- and long-term recommendations on how to solve UAV icing issues. NOTE: SAE EDGE™ Research Reports are intended to identify and illuminate key issues in emerging, but still unsettled, technologies of interest to the mobility industry. The goal of SAE EDGE™ Research Reports is to stimulate discussion and work in the hope of promoting and speeding resolution of identified issues. SAE EDGE™ Research Reports are not intended to resolve the challenges they identify or close any topic to further scrutiny. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2020008
Book Synopsis Unsettled Issues Concerning Automated Driving Services in the Smart City Infrastructure by : Serge Lambermont
Download or read book Unsettled Issues Concerning Automated Driving Services in the Smart City Infrastructure written by Serge Lambermont and published by SAE International. This book was released on 2021-12-15 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information and communication technology is fundamentally changing the way we live and operate in cities, such as instant access to events, transportation, bookings, payments, and other services. At the same time, three “megatrends” in the automotive industry—self-driving, electrification, and advanced manufacturing technology—are enabling the design of innovative, application-specific vehicles that capitalize on city connectivity. Applications could countless; however, they also need to be safe and securely integrated into a city’s physical and digital infrastructure, and into the overall urban ecosystem. Unsettled Issues Concerning Automated Driving Services in the Smart City Infrastructure examines the current state of the industry, the developments in automated driving and robotics, and how these new urban, self-driving city applications are different. It also analyzes higher level challenges for urban applications. Ultimately, this report includes several options for sharing lessons learned among different cities and their stakeholders. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2021030
Book Synopsis Unsettled Topics Concerning Flying Cars for Urban Air Mobility by : Yangjun Zhang
Download or read book Unsettled Topics Concerning Flying Cars for Urban Air Mobility written by Yangjun Zhang and published by SAE International. This book was released on 2021-05-24 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flying cars—as a new type of vehicle for urban air mobility (UAM)—have become an important development trend for the transborder integration of automotive and aeronautical technologies and industries. This article introduces the 100-year history of flying cars, examines the current research status for UAM air buses and air taxis, and discusses the future development trend of intelligent transportation and air-to-land amphibious vehicles. Unsettled Topics Concerning Flying Cars for Urban Air Mobility identifies the major bottlenecks and impediments confronting the development of flying cars, such as high power density electric propulsion, high lift-to-drag ratio and lightweight body structures, and low-altitude intelligent flight. Furthermore, it proposes three phased goals and visions for the development of flying cars in China, suggesting the development of a flying vehicle technology innovation system that integrates automotive and aeronautic industries. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2021011
Book Synopsis Unsettled Issues Concerning eVTOL for Rapid-response, On-demand Firefighting by : Johnny Doo
Download or read book Unsettled Issues Concerning eVTOL for Rapid-response, On-demand Firefighting written by Johnny Doo and published by SAE International. This book was released on 2021-08-26 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advancements of electric vertical takeoff and landing (eVTOL) aircraft have generated significant interest within and beyond the traditional aviation industry. One promising application for these innovative systems is in firefighting support during urban, rural, and wildland firefighting operations. Future eVTOL firefighting capabilities could include early detection and suppression, civilian rescue, and on-demand aerial deployment and extraction of firefighters. Unsettled Issues Concerning eVTOL for Rapid-response, On-demand Firefighting identifies the challenges to be addressed so that these capabilities and benefits could be realized at scale: Firefighting-specific eVTOL vehicle development Sense and avoid capabilities in smoke-inhibited environments Autonomous and remote operating capabilities Charging system compatibility and availability Operator and controller training Dynamic air space management Vehicle/fleet logistics and support First-responder and general public acceptance Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2021017
Book Synopsis Unsettled Topics in the General Aviation Autonomy Landscape by : Anna Mracek Dietrich
Download or read book Unsettled Topics in the General Aviation Autonomy Landscape written by Anna Mracek Dietrich and published by SAE International. This book was released on 2022-02-24 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The extent of automation and autonomy used in general aviation (GA) has been accelerating dramatically. This has huge potential benefits for safety given that 75% of accidents in personal and on-demand GA are due to pilot error. However, an approach to certifying autonomous systems that relies on reversionary modes limits their potential to improve safety. Placing a human pilot in a situation where they are suddenly tasked with flying an airplane in a failed situation, often without sufficient situational awareness, is overly demanding. This, coupled with advancing technology that may not align with a deterministic certification paradigm, creates an opportunity for new approaches to certifying autonomous and highly automated aircraft systems. Unsettled Topics in the General Aviation Autonomy Landscape discusses how these new approaches must account for the multifaceted aviation approach to risk management which has interlocking requirements for airworthiness and operations (including training and airspace integration). If implemented properly, autonomy can take GA safety to the next level while simultaneously increasing the number and variety of aircraft and transportation options they provide. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2022004
Book Synopsis Unsettled Technology Domains for Pathways to Automotive Decarbonization by : Jody Emlyn Muelaner
Download or read book Unsettled Technology Domains for Pathways to Automotive Decarbonization written by Jody Emlyn Muelaner and published by SAE International. This book was released on 2020-07-22 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Replacing fossil-fueled vehicles with battery-electric ones is a risky strategy. It is likely to be limited by the supply of metals critical to battery and solar cell production, and the investment required in decarbonized electricity. Using hydrogen to store renewable energy would greatly reduce efficiency, further increasing the investment required to decarbonize the electricity supply. The lowest technical risk and most economical pathway to decarbonization is reducing private car use. Shorter journeys would be made by walking and cycling – also known as “active travel” – with public transport used for most longer journeys. Realizing this cultural change in transport behavior will first require comprehensive networks for safe and enjoyable active travel, which separate walking and cycling. All locations should connect to either a fully segregated cycleway or traffic calmed roadways with a maximum speed of 30 kph. Active travel investment can save money due to improved public health, eliminate the 11% of carbon emissions caused by short car journeys, and facilitate public transport by empowering people to reach their final destination. Bicycle manufacturing is growing rapidly and further innovations in transport cycles and other lightweight vehicles compatible with an active travel infrastructure will boost this growth. Increased use of public transportation is vital to efficiently use the limited availability of decarbonized electricity. Autonomous vehicles in private use may increase vehicle miles, but autonomous operation within public transportation systems could be transformative. The remaining private cars, buses, and heavy goods vehicles could be electrified more cost effectively using electric road systems. These enable unlimited range and smaller batteries, with the lowest societal cost of any private car-based decarbonization pathway. Although users may pay higher road tax or tolls for the infrastructure, this is easily offset by greatly reduced vehicle costs and improved efficiency. Electrification needs to be brought initially to city bus networks and heavily used transport corridors. Wider use will require standardization and investment at the federal level or continental level. NOTE: SAE EDGE™ Research Reports are intended to identify and illuminate key issues in emerging, but still unsettled, technologies of interest to the mobility industry. The goal of SAE EDGE™ Research Reports is to stimulate discussion and work in the hope of promoting and speeding resolution of identified issues. SAE EDGE™ Research Reports are not intended to resolve the issues they identify or close any topic to further scrutiny. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2020014
Book Synopsis Unsettled Impacts of Integrating Automated Electric Vehicles into a Mobility-as-a-Service Ecosystem and Effects on Traditional Transportation and Ownership by : Joachim Taiber
Download or read book Unsettled Impacts of Integrating Automated Electric Vehicles into a Mobility-as-a-Service Ecosystem and Effects on Traditional Transportation and Ownership written by Joachim Taiber and published by SAE International. This book was released on 2019-12-20 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 space for vehicles that are inactive most of the time. A key challenge is the transition phase where traditional forms of car ownership and transportation coexist with new forms of mobility services (before true MaaS platforms are fully optimized). Another fundamental issue is determining the true cost of car ownership and establishing ideal cost structures for on-demand mobility services in order to replace the need of owning a car. This needs to occur without compromising subsidized public transportation which provides affordable transportation for low-income groups. NOTE: SAE EDGE™ Research Reports are intended to identify and illuminate key issues in emerging, but still unsettled, technologies of interest to the mobility industry. The goal of SAE EDGE™ Research Reports is to stimulate discussion and work in the hope of promoting and speeding resolution of identified issues. SAE EDGE™ Research Reports are not intended to resolve the issues they identify or close any topic to further scrutiny. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2019004
Book Synopsis Unsettled Issues in Advanced Air Mobility Certification by : Bob McQueen
Download or read book Unsettled Issues in Advanced Air Mobility Certification written by Bob McQueen and published by SAE International. This book was released on 2021-06-18 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced air mobility (AAM) refers to urban transportation systems that move people and goods by air. This has significant implications for reducing traffic congestion in cities and for providing an integrated approach to urban mobility. With the emergence of drone technology and the possibility of more autonomous aircraft, interest has grown considerably in AAM. Unsettled Issues in Advanced Air Mobility Certification discusses the impact of AAM on private sector solution providers including aerospace and technology companies and goes into solutions for urban planners and transportation professionals for better integration across all AAM modes. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2021014
Book Synopsis Unsettled Domains Concerning Autonomous System Validation and Verification Processes by : Fabio Alonso da Silva
Download or read book Unsettled Domains Concerning Autonomous System Validation and Verification Processes written by Fabio Alonso da Silva and published by SAE International. This book was released on 2019-12-30 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Federal Aviation Administration (FAA) and the Department of Transportation’s (DOT’s) National Highway Traffic Safety Administration (NHTSA) face similar challenges regarding the regulation of autonomous systems powered by artificial intelligence (AI) algorithms that replace the human factor in the decision-making process. Validation and verification (V&V) processes contribute to implementation of correct system requirements and the development life cycle - starting with the definition of regulatory, marketing, operational, performance, and safety requirements. The V&V process is one of the steps of a development life cycle starting with the definition of regulatory, marketing, operational, performance, and safety requirements. They define what a product is, and they flow down into lower level requirements defining control architectures, hardware, and software. The industry is attempting to define regulatory requirements and a framework to gain safety clearance of such products. This report suggests a regulatory text and a safety and V&V approach from an aerospace engineering perspective assessing the replacement of the human driver from the decision-making role by a computational system. It also suggests an approach where aerospace guidelines can be used alongside the International Organization for Standardization (ISO) standard ISO 26262 in order to define a viable and valuable framework for autonomous systems safety clearance (or certification). NOTE: SAE EDGE™ Research Reports are intended to identify and illuminate key issues in emerging, but still unsettled, technologies of interest to the mobility industry. The goal of SAE EDGE™ Research Reports is to stimulate discussion and work in the hope of promoting and speeding resolution of identified issues. SAE EDGE™ Research Reports are not intended to resolve the issues they identify or close any topic to further scrutiny. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2019012
Book Synopsis Unsettled Issues in Drive-by-Wire and Automated Driving System Availability by : Jeff Hemphill
Download or read book Unsettled Issues in Drive-by-Wire and Automated Driving System Availability written by Jeff Hemphill and published by SAE International. This book was released on 2022-01-28 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: While many observers think that autonomy is right around the corner, there many unsettled issues. One such issue is availability, or how the vehicle behaves in the event of a failure of one of its systems such as those with the latest “by-wire” technologies. Handling of failures at a technical actuation level could involve many aspects, including time of operation after first fault, function/performance after first fault, and exposure after first fault. All of these and other issues are affected by software and electronic and mechanical hardware. Drive-by-wire and Automated Driving System Availability discusses the necessary systems approach required to address these issues. Establishing an industry path forward for these topics will simplify system development and provide a framework for consistent regulation and liability, which is an enabler for the launch of autonomous vehicles. Click here to access the full SAE EDGETM Research Report portfolio. https://doi.org/10.4271/EPR2022002
