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研发设计收录论文、预印本和会议论文;标题保留原文,预印本与设计目标请核对原文。未经过编辑判断的资料展示在全部动态中。

2023年9月11日周一
  1. arXiv eVTOL预印本历史资料

    The Feasibility of Electric Air Taxis: Balancing Time Savings and CO$_2$ Emissions -- A joint case study of respective plans in Paris

    This paper evaluates the sustainability of Advanced Air Mobility (AAM) in urban and regional mobility, using Paris as a case study. Paris is committed to eco-friendly transportation and has introduced AAM, including electric Vertical Take-Off and Landing (eVTOL) air taxis for the 2024 Olympic Games. We assess eVTOL energy consumption and CO$_2$ emissions on urban and regional routes, comparing them with cars, public transport, and helicopters. Urban eVTOLs save around 23 minutes over cars and 22 minutes over public transport on 50 km routes. For regional routes (300 km), eVTOLs save 76 minutes over cars and 69 minutes over trains. However, eVTOLs' eco-friendliness depends on context. In urban areas, they consume more energy than electric cars, but beat traditional helicopters by 47%. For regional travel, eVTOLs outperform helicopters and some cars but lag behind electric vehicles and trains. To maximize AAM's sustainability in Paris, stakeholders must consider real-world operations and integrate eVTOLs into the broader transportation system. This approach can lead to greener urban and regional transportation.(预印本;同行评审状态请核对原文。)

2023年8月19日周六
  1. arXiv eVTOL预印本历史资料

    Reliability and Delay Analysis of 3-Dimensional Networks with Multi-Connectivity: Satellite, HAPs, and Cellular Communications

    Aerial vehicles (AVs) such as electric vertical take-off and landing (eVTOL) aircraft make aerial passenger transportation a reality in urban environments. However, their communication connectivity is still under research to realize their safe and full-scale operation. This paper envisages a multi-connectivity (MC) enabled aerial network to provide ubiquitous and reliable service to AVs. Vertical heterogeneous networks with direct air-to-ground (DA2G) and air-to-air (A2A) communication, high altitude platforms (HAPs), and low Earth orbit (LEO) satellites are considered. We evaluate the end-to-end (E2E) multi-hop reliability and network availability of the downlink of AVs for remote piloting scenarios, and control/telemetry traffic. Command and control (C2) connectivity service requires ultra-reliable and low-latency communication (URLLC), therefore we analyse E2E reliability and latency under the finite blocklength (FBL) regime. We explore how different MC options satisfy the demanding E2E connectivity requirements taking into account antenna radiation patterns and unreliable backhaul links. Since providing seamless connectivity to AVs is very challenging due to the line-of-sight (LoS) interference and reduced gains of downtilt ground base station (BS) antennas, we use coordinated multi-point (CoMP) among ground BSs to alleviate the inter-cell interference. Furthermore, we solve an optimization problem to select the best MC path under the quality of service (QoS) constraints. We maximize spectral efficiency (SE) to specify the optimum MC path with the minimum number of requ(预印本;同行评审状态请核对原文。)

2023年7月31日周一
  1. arXiv eVTOL预印本历史资料

    Thermo-mechanical level-set topology optimization of a load carrying battery pack for electric aircraft

    A persistent challenge with the development of electric vertical take-off and landing vehicles (eVTOL) to meet flight power and energy demands is the mass of the load and thermal management systems for batteries. One possible strategy to overcome this problem is to employ optimization techniques to obtain a lightweight battery pack while satisfying structural and thermal requirements. In this work, a structural battery pack with high-energy-density cylindrical cells is optimized using the level-set topology optimization method. The heat generated by the batteries is predicted using a high-fidelity electrochemical model for a given eVTOL flight profile. The worst-case scenario for the battery's heat generation is then considered as a source term in the weakly coupled steady-state thermomechanical finite element model used for optimization. The objective of the optimization problem is to minimize the weighted sum of thermal compliance and structural compliance subjected to a volume constraint. The methodology is demonstrated with numerical examples for different sets of weights. The optimized results due to different weights are compared, discussed, and evaluated with thermal and structural performance indicators. The optimized pack topologies are subjected to a transient thermal finite element analysis to assess the battery pack's thermal response.(预印本;同行评审状态请核对原文。)

2023年7月7日周五
  1. arXiv eVTOL预印本历史资料

    Physics-Infused Machine Learning Based Prediction of VTOL Aerodynamics with Sparse Datasets

    Complex optimal design and control processes often require repeated evaluations of expensive objective functions and consist of large design spaces. Data-driven surrogates such as neural networks and Gaussian processes provide an attractive alternative to simulations and are utilized frequently to represent these objective functions in optimization. However, pure data-driven models, due to a lack of adherence to basic physics laws and constraints, are often poor at generalizing and extrapolating. This is particularly the case, when training occurs over sparse high-fidelity datasets. A class of Physics-infused machine learning (PIML) models integrate ML models with low-fidelity partial physics models to improve generalization performance while retaining computational efficiency. This paper presents two potential approaches for Physics infused modelling of aircraft aerodynamics which incorporate Artificial Neural Networks with a low-fidelity Vortex Lattice Method model with blown wing effects (BLOFI) to improve prediction performance while also keeping the computational cost tractable. This paper also develops an end-to-end auto differentiable open-source framework that enables efficient training of such hybrid models. These two PIML modelling approaches are then used to predict the aerodynamic coefficients of a 6 rotor eVTOL aircraft given its control parameters and flight conditions. The models are trained on a sparse high-fidelity dataset generated using a CHARM model. The trained models are then compared against the vanilla low-fidelity model and a standard pure data-driv(预印本;同行评审状态请核对原文。)