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Flying cars, or vertical takeoff and landing (VTOL) aircraft, are revolutionary devices that can address traffic congestion and help build a three-dimensional transportation system in the future. Flight safety could deteriorate in actual flight because ducted fans may suffer from significant thrust fluctuations induced by crosswinds. In this article, we propose a variable-speed control method to reduce thrust fluctuations by applying a speed waveform opposite to the fluctuation waveform. We choose a typical condition of a 5 m/s crosswind for validation. The results of unsteady Reynolds averaged Navier‒Stokes (URANS) calculations show that crosswinds lead to fluctuations in all thrusts with the frequency of the blade passing frequency. The total thrust fluctuation amplitude accounts for 6.2% of the total thrust. By applying the variable-speed control where the frequency is identical to the thrust fluctuation frequency, the phase difference is 180 degrees, and the amplitude is approximately the square root of the fluctuation amplitude, the standard deviation of the thrust fluctuation is reduced by 92% without affecting the mean total thrust. Fluctuations in other performance parameters, such as lateral force and pitching moment, are improved as well. This active control method can achieve accurate control without any auxiliary equipment and has good application prospects. It provides a promising idea for solving the problem of performance fluctuations in turbomachinery. [ABSTRACT FROM AUTHOR]

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(1) Introduction: Transportation logistics play a pivotal role in facilitating both individual mobility and supply chain operations on a global scale. However, conventional transportation systems have contributed significantly to urban congestion and environmental degradation. In response to these challenges, there is growing momentum to investigate the potential of renewable energy to power electric vehicles (EVs) and flying automobiles, aiming to reduce fossil fuel dependence and carbon emissions. (2) Objectives: By analyzing key drivers and opportunities for integrating flying vehicles into existing infrastructure through dynamic modeling, this study seeks to accelerate the transition to sustainable transportation. (3) Methodology: A mixed-method approach, combining literature review and causal loop diagram analysis, is employed to understand the factors influencing EV and flying car adoption. (4) Results: Findings highlight the significant potential of renewable energy in reducing emissions and reliance on fossil fuels through widespread EV and flying vehicle adoption. The major drivers and challenges in infrastructure, safety, and airspace management are also identified. In addition, this research emphasizes the importance of sustainable transportation in addressing urban congestion, pollution, and energy security. (5) Conclusions: By leveraging renewable energy and embracing technological advancements, a low-carbon future for transportation can be achieved, benefiting both the environment and society. [ABSTRACT FROM AUTHOR]

As this Special Section goes to publication, semiconductor manufacturing in the United Status, and globally, continues to expand at a seemingly torrid pace. Assisted by government funding and driven in part by artificial intelligence workloads that gobble up increasing amounts of data center computing capacity, Intel and TSMC fabs are going up in Arizona, TI and Samsung fabs are coming to Texas, and Micron has big plans in New York. Unfortunately, just like those flying cars we were once promised, AI has not yet eliminated the need for the skilled trades and engineers required to build and successfully operate a fab. As a result, workforce development has become an important part of the increasingly complex semiconductor manufacturing process: Where are the thousands of engineers the semiconductor industry needs to staff these new fabs going to come from? How can we make more students excited about science and engineering? While the Guest Editors don’t have all the answers, we are happy that ASMC contributes to the solution by actively supporting student presentations and posters and annually recognizing the best student paper of the conference. And, maybe some day, the artificial intelligence systems that semiconductor manufacturing has enabled will give us those Star Wars or Star Trek robots that can build fabs and make chips too. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electric tilt-wing flying cars are an efficient, economical, and environmentally friendly solution to urban traffic congestion and travel efficiency issues. This article addresses the high energy consumption and obstacle interference during the takeoff phase of the tilt-wing eVTOL (electric Vertical Takeoff and Landing), proposing a trajectory planning method based on energy minimization and obstacle avoidance. Firstly, based on the dynamics analysis, the relationship between energy consumption, spatial trajectory, and obstacles is sorted out and the decision variables for the trajectory planning problem with obstacle avoidance are determined. Secondly, based on the power discretization during the takeoff phase, the energy minimization objective function is established and the constraints of performance limitations and spatial obstacles are derived. Thirdly, by integrating the optimization model with the SLSQP (Sequential Least Squares Quadratic Programming algorithm), the second-order sequential quadratic programming model and decision variable update equations are derived, establishing the solution process for the trajectory planning problem of the tilt-wing eVTOL takeoff with obstacle avoidance. Finally, the Airbus Vahana A3 is taken as an example to verify and validate the effectiveness, stability, and robustness of the model and optimization algorithm proposed. The validation results show that the OTPEM (obstacle avoidance trajectory planning methodology based on energy minimization) can effectively handle changes in the takeoff end state and exhibits good stability and robustness in different obstacle environments. It can provide a certain reference for the three-dimensional obstacle avoidance trajectory planning of Airbus Vahana A3 and other tilt-wing eVTOL trajectory planning problems. [ABSTRACT FROM AUTHOR]

Flying cars offer huge advantages due to their deformable structure, which can adapt to external environments and mission requirements. They represent a novel system that can realize vertical takeoff and landing. However, the structure of a flying car is complicated, placing higher requirements on modeling accuracy and control effectiveness. Thus, in this paper, a dynamic model of a flying car is proposed by combining a car body, motor, and propellers. Then, a double-loop controller based on active disturbance rejection control is proposed to accurately control its flight altitude. Utilizing the extended state observer, external wind and other disturbances are regarded as an extended state, which can be dynamically observed and compensated to significantly improve tracking accuracy. The effectiveness of the proposed controller is validated through detailed simulations and flight experiments. The proposed controller significantly improves control accuracy and disturbance rejection capability. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Foreign Policy Journal (CFPJ) is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Blade Runner (1982), directed by Ridley Scott and adapted from Philip K. Dick's Do Androids Dream of Electric Sheep? (1968), incorporates the media of film and photography and utilizes various filmmaking techniques, including cinematography, sound effects, and dialogues, to reflect on the complex relationship between humans, technology and power. Through cinematographic techniques such as light and dark contrast, shifting eye-level and high camera angles, as well as geometric patterns, the film portrays a technologically-advanced futuristic city and its underlying issues of power struggles and social hierarchy. The portrayal of replicants, through static and moving images and sound effects, emphasizes their close resemblance to humans, particularly their performance of emotions, and how technology alters the fundamental concept of humanity. Photography, as a medium, captures an unreliable and incomplete moment of childhood to expose the dystopian nightmare of memory manipulation that severs the connection between memory and identity. This article analyses Blade Runner as an intermedial narrative that highlights the tension between the deceptive appearance of a futuristic city, with flying cars, replicants, and other technologies created for human convenience, and the harsh reality of posthuman crises such as social hierarchy, technological dominance, memory manipulation, and replicant rebellion. [ABSTRACT FROM AUTHOR]

This article was written to investigate the research on the scientific directions for flying cars at the preliminary design stage to provide a rationale for the choice of scientific research in the area of flying cars. At present, the population of the Earth is gradually increasing, and traffic congestion will become a common phenomenon in cities in the future. This work used the methods of theoretical and statistical analysis to form an overall picture of this area of research. We researched the statistical data analysis conducted by scientists who dealt with flying cars and the associated issues. We gave a rationale for the choice of the object of scientific research, which is flying cars. People can read this information to have a starting point in their understanding of flying car design. This analysis of famous scientific works provides possible scientific directions that the research can take with respect to designing a flying car that combines the advantages of an airplane and a car and can take off and land on a normal highway for a short distance, as well as help people reach their destination quickly and easily. [ABSTRACT FROM AUTHOR]

Urban air mobility is a relatively new concept that has been proposed in recent years as a means of transporting passengers and goods in urban areas. It encompasses a diverse range of Vertical TakeOff and Landing (VTOL) vehicles that function more like passenger-carrying drones for on-demand transportation. Among them, the car-like VTOL is advantageous due to its compact configuration, safe rotors, high user affinity, and technological fashion. These characteristics are frequently derived from the flying car's Ducted Fan Lift System (DFLS). This study aims to develop a method for the rapid design and the evaluation of the aerodynamic performance of the DFLS, to support the preliminary scheme demonstration of the ducted fan flying car. The proposed method uses blade element theory to design the unducted fan and applies momentum theory to calculate the aerodynamic thrust of the DFLS. The DFLS of a 1:3 scale verifier for a flying car scheme was designed and evaluated using the proposed method and a numerical method, respectively. To validate the proposed method, a prototype of the scale DFLS was manufactured and tested, and the result was compared with those of the proposed theoretical method and the numerical method. This study demonstrates that while both the theoretical and numerical methods are capable of designing an unducted fan accurately, the theoretical method is simpler and faster. Compared to the DFLS test results, the theoretical method's average difference is approximately 1.9%. When evaluating the DFLS, the accuracy of the numerical calculation is reduced, and the difference is greater than 30% at low power. The theoretical method presented in this paper can be used to improve the aerodynamic design and evaluation efficiency of the DFLS and to aid in the configuration evaluation of VTOLs equipped with ducted fans. [ABSTRACT FROM AUTHOR]

Due to the high power-to-weight ratio characteristic of turboshaft engines, the power generation unit based on it holds immense potential in the hybrid electric propulsion system (HEPS) of flying cars. To mitigate environmental pollution and reduce fuel consumption, while enhancing the fuel economy of turboshaft engine power generation unit (TEPGU) across the entire power output range, this paper investigates a dual-motor electronic regulation architecture for twin-shaft TEPGU. According to the different variable combinations of TEPGU architecture, two modes and their respective fuel-economy-optimal power regulations are proposed. Initially, by considering the efficiency distribution of motors, we construct an Extended co-working balance model based on the Newton-Raphson method. Subsequently, different operating modes are proposed and discussed, studying the characteristic laws of the power generation unit under each mode. For the variable speed mode and the power split mode, this article proposes a shaft-speed-feature-projective searching (SFPS) method and a multi-dimensions-feature-projective searching (MFPS) method based on characteristic dimensionality reduction projection. Finally, a comparative analysis of the fuel-saving effects of the SFPS and MFPS regulation methods is conducted, and the reasons for enhancing fuel efficiency are discussed. The simulation results show that the model of TEPGU is in good agreement with the experimental data, and the error of specific fuel consumption(SFC) in the full power range is less than 5.7 %. Besides, comparative results indicate that the strategies based on MFPS and SFPS can achieve a maximum instantaneous fuel consumption reduction of 14.38 % and 10.82 %, respectively. The MFPS strategy exhibits a fuel consumption saving of 12.69 % throughout the driving cycle, demonstrating superior performance in fuel economy. • A dual motor regulation architecture for turboshaft engine is proposed. • Discuss the rules of variable speed mode and power split mode. • Propose optimal fuel regulation methods for SFPS and MFPS based on laws. • Verify the fuel economy advantages of methods under land air cycle conditions. [ABSTRACT FROM AUTHOR]

Flying cars, also known as Vertical Takeoff and Landing aircraft (VTOLs), can significantly improve transportation efficiency, and are expected to play an important role in future transportation. However, the technical requirements to make electric flying cars economically feasible remains insufficiently investigated. In this study, with detailed cost calculation model, the levelized cost and profit of electric flying car operation are estimated. The results show that under the base case (250 Wh/kg battery, baseline cost, battery swapping, no unmanned autonomous driving systems), the levelized cost is $0.61/passenger-km, about one-third higher than on-road taxi cost. Under passenger fare of $1.00/passenger-km, the net present value is $0.46 million, which implies an investment return cycle of 5 years, comparable to the airline industry. Advanced technology deployment can significantly improve profitability. With battery specific energy increased to 400 and 600 Wh/kg, the net present value increases by 60 % and 72 %. The investment return cycle can be reduced to 3 and 2 years, making electric flying car operation a high-profitability industry comparable to ride-sharing. The use of unmanned autonomous driving systems can drive net present value up to 4.2 times that under the base case, implying an investment return cycle of 2 years. Compared with battery swapping, charging as the energy supplementing approach leads to lower operation efficiency, but can be compensated by fast-charging and the reduction of battery capacity. The results suggest that the electric flying car industry could take full advantage of on-road-vehicle battery technology development. Efforts should be made in establishing a complete air-ground joint management system to facilitate unmanned autonomous driving. • VTOLs can make economic sense with improvements in key technologies. • A 400 Wh/kg battery is a proper option to make eVTOLs economically feasible. • EVTOLs should take full advantage of vehicle battery technology development. • Unmanned autonomous driving is crucial for the commercialization of eVTOLs. [ABSTRACT FROM AUTHOR]

Recent research and development activities in both in aviation and automotive industries resulted with a genuine product known as roadable aircraft also known as flying car. Roadable aircraft is combination of a small size airplane and a passenger vehicle containing the superior sides of both products; and provides door-to-door transportation by both ground and air. Many companies invested in this product and first commercial units are expected to be the launched within 5 years. Suspension system of a roadable aircrafts plays a significant role in the overall product design, as it should satisfy the customer requirements for both aircrafts and passenger cars: landing and traveling on road. In this study, suspension system of a flying car was modelled in Matlab/Simulink and optimized as a quarter car model employing a 2 DOF Mass-Spring-Damper system. The equations of motion were presented, and the model was firstly simulated as an aircraft landing gear for landing performance. Then the model was run to determine driving performance on road for a typical bump passing manoeuvre. A set of design parameters was determined for acceptable performance outputs: suspension system damping element acting force and displacement for the landing and maximum acceleration for the bump passing performance. [ABSTRACT FROM AUTHOR]

Different from traditional transport systems, such as cars or trains, which are limited by land transit space, flying cars (such as UAS, drones, and air taxis) do not occupy space with traffic. They have a degree of freedom in space and time, smaller displacement, and consequently, less stress for their users. Large companies and researchers around the world are working with different architectures, algorithms, and techniques to test air taxi transport to serve a significant proportion of people safely and autonomously. One of the main issues surrounding the diffusion of air taxis is safety and security, since a simple failure can lead to the loss of high-value assets, loss of the vehicle, and/or injuries to human lives, including fatalities. In this sense, despite significant efforts, the literature is still specific and limited regarding air taxi safety and security. Therefore, this study aimed to carry out an extensive systematic literature review of the main modern advances in techniques, architectures, and research carried out around the world focused on these types of vehicles. More than 210 articles from between 2015 and January 2022 were individually reviewed. In addition, this study also presents gaps that could serve as a direction for future research. As far as the authors are aware, no other study performs this type of review focused on air taxi safety. [ABSTRACT FROM AUTHOR]

Summary: Flying car is an effective transport to solve current traffic congestion. The power batteries in flying cars discharge at a high current rate in the takeoff and landing phase, evoking a severe thermal issue. Flat heat pipe (FHP) is a relatively new type of battery thermal management technology, which can effectively maintain the temperature uniformity of the battery pack. We have constructed a resistance‐based thermal model of the batteries considering the impact of the state of charge (SOC), battery temperature, and current on the battery heat generation. The FHP model is developed based on segmental heat conduction model, and integrated into the battery model to form the battery‐FHP‐coupled model for a battery module. Experiments are carried out to verify its accuracy. Then, the battery thermal performance is analyzed under the different discharging conditions including constant discharge rates and dynamic discharge rates for flying cars. Under the condition of the flying cars, the battery maximum temperature appears at the end of takeoff stage, while the maximum temperature difference appears during the forward flight segment. Moreover, different FHP heat dissipation structures are studied to further improve the battery thermal performance. The configuration with the best performance is adopted for the battery pack, and it can meet the heat dissipation requirements of the pack at a discharge rate of 3C or that of flying cars. Finally, the influence of inlet cooling air velocity and temperature on battery thermal performance is investigated. According to the research results, air velocity has little effect on the battery maximum temperature at the discharge rate of flying cars, but it can obviously affect the temperature decrease rate. Besides, the battery maximum temperature and its temperature difference develop linearly with the air temperature. [ABSTRACT FROM AUTHOR]

This paper presents an image-processing technique for cabin delivery employing local localization and docking in a mobile station, which is a mobile vertiport for the use of dual-mode flying cars. A dual-mode flying automobile with an aerial electric vehicle (AEV), a ground electric vehicle (GEV), and a cabin is a future method of transportation that can be used in both the air and on the ground. To enable AEVs to land in a specific position, a landing site is necessary. The proposed AEV uses vertical take-off and landing, and a vertiport landing site is required. As vertical take-off and landing sites require a lot of space and are challenging to operate in multiple positions, we suggest a mobile vertiport that can fit into a small space. A mobile station is appropriate for dual-mode flying cars since it includes critical activities such as transporting AEVs from the ground and charging as well as a cabin-delivery system. The mobile station can generate a path to the AEV by calculating the relative position using the markers attached to the AEV and estimating the position of the landing AEV. The mobile station detects a marker for precise positioning correction, followed by exact position correction for cabin delivery, to travel to the accurate position of the AEV. To increase the success rate of cabin delivery, docking markers are identified and the angle position error between the mobile station and cabin is computed and corrected to rectify the position between the cabin and the mobile station for cabin delivery. In addition, the experimental results revealed a mechanically correctable error range that encompassed all experimental values. Consequently, this study showed that image processing may be used to create a mobile station for dual-mode flying automobiles. [ABSTRACT FROM AUTHOR]

In terms of future transportation, flying cars are envisioned not only as air taxis but also as air ambulances. Flying cars such as urban air mobility vehicles, passenger drones, and electrical vertical take-off and landing (eVTOL) aircrafts have the potential to relieve seriously congested ground traffic in cities via direct point-to-point air movements. To date, conventional research in which the airframe of a flying car is optimized for use in medical emergencies has not identified a sustainable solution. The purpose of this study is to verify the technical applicability of a flying car for use in medical emergencies. The weighted sum method is used to optimize the design of multi-rotor, vectored-thrust (tilt-rotor), and lift + cruise types of flying cars. A simulation scenario that considers cruising speed and flight height is conducted based on an analysis of stakeholder interviews with a pilot, an in-flight doctor, and an operating company. To optimize the parameters of a flying car airframe, four objective functions, namely the energy required for a round trip, noise value from rotors, downwash speed from rotors, and landing area size, are chosen because the results of a requirement analysis revealed that they were significant for the sustainability of the flying car system. The results of the simulation reveal that the required battery energy densities for all three types exceed the current lithium-ion battery capacities. Therefore, an upgrade in battery capacity is critical for the realization of a flying car. Although the noise level is found to be less than that of a conventional helicopter, it is necessary to develop a rotor to decrease noise levels for environmental reasons. Finally, both the downwash speed and landing area of a flying car are estimated to be less than those of a conventional helicopter, making it possible for the flying car to land in tight spaces. [ABSTRACT FROM AUTHOR]

A flying electric car in the smart city is a type of personal air vehicle that provides door-to-door transportation by both ground and air. In this article, we review the latest developments in flying cars. The autonomous flying car detects and evaluates the environment, uses digital technologies to control and navigate itself without collision, travels in space, can take off and land (VTOL), and uses electric propulsion. Today, several companies are developing flying cars: Terrafugia, Aero Mobil, Volocopter, Lilium, Hyundai, Uber, Bosch. Many prototypes have been built in the last years using a variety of flight technologies and some have true VTOL performance. [ABSTRACT FROM AUTHOR]

Disappointingly to many who grew up at the time, promises of flying cars in the 1960s as a future form of urban transportation were not kept. That future never arrived. In this short commentary, I want to board the metaphorical flying car and steer it into a different direction. At the height of the first wave of Covid-19, a more widespread sentiment took hold that saw the anticipation of increased mobilities dashed by a general anticipation of disaster considered typical for our age today. We might conclude: We don't get the technologies we want because we have left the era of technological progress and entered the era of risk and anticipation of disaster. My commentary appreciates and discusses the lessons we can learn from Splintering Urbanism for our period of pandemic urbanism. How does the kind of networked urbanism that the book examines and critiques provide a framework in which we can understand the emergence, presence, and management of the pandemic as it affects our urban world today? [ABSTRACT FROM AUTHOR]