Frontiers in Aerospace Engineering最新文献_第2页

Predicting sUAS conflicts in the national airspace with interacting multiple models and Haversine-based conflict detection system 基于交互多模型和haversine冲突检测系统的国家空域sUAS冲突预测

Frontiers in Aerospace Engineering Pub Date : 2023-05-10 DOI: 10.3389/fpace.2023.1184094

James Z. Wells, Manish Kumar

{"title":"Predicting sUAS conflicts in the national airspace with interacting multiple models and Haversine-based conflict detection system","authors":"James Z. Wells, Manish Kumar","doi":"10.3389/fpace.2023.1184094","DOIUrl":"https://doi.org/10.3389/fpace.2023.1184094","url":null,"abstract":"In this paper, a conflict detection system for small Unmanned Aerial Vehicles (sUAS), composed of an interacting multiple model state predictor and a Haversine-distance based conflict detector, is proposed. The conflict detection system was developed and tested via a random recursive simulation in the ROS-Gazebo physics engine environment. The simulation consisted of ten small unmanned aerial vehicles flying along randomly assigned way-point navigation missions within a confined airspace. Way-points are generated from a uniform distribution and then sent to each vehicle. The interacting multiple model state predictor runs on a ground-based system and only has access to current vehicle positional information. It does not have access to the future way-points of individual vehicles. The state predictor is based on Kalman filters that utilize constant velocity, constant acceleration, and constant turn models. It generates near-future position estimates for all vehicles operating within an airspace. These models are probabilistically fused together and projected into the near-future to generate state predictions. These state predictions are then passed to the Haversine distance-based conflict detection algorithm to compare state estimates and identify probable conflicts. The conflicts are detected and flagged based on tunable threshold values which compare distances between predictions for the vehicles operating within the airspace. This paper discusses the development of the random recursive simulation for the ROS-Gazebo framework and the derivation of the interacting multiple model along-with the Haversine-based future conflict detector. The results are presented via simulation to highlight mid-air conflict detection application for sUAS operations in the National Airspace.","PeriodicalId":365813,"journal":{"name":"Frontiers in Aerospace Engineering","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116662869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical and boundary condition effects on the prediction of detonation engine behavior using detailed numerical simulations 数值和边界条件对爆震发动机性能预测的影响

Frontiers in Aerospace Engineering Pub Date : 2023-04-26 DOI: 10.3389/fpace.2023.1123249

Takuma Sato, Caleb Van Beck, V. Raman

{"title":"Numerical and boundary condition effects on the prediction of detonation engine behavior using detailed numerical simulations","authors":"Takuma Sato, Caleb Van Beck, V. Raman","doi":"10.3389/fpace.2023.1123249","DOIUrl":"https://doi.org/10.3389/fpace.2023.1123249","url":null,"abstract":"High-fidelity numerical simulations of an experimental rotating detonation engine with discrete fuel/air injection were conducted. A series of configurations with different feed-plenum pressures but with constant equivalence ratio were studied. Detailed chemical kinetics for the hydrogen/air system is used. A resolution study for the full rotating detonation engine (RDE) system simulation is also conducted. Two kinds of boundary conditions, a total pressure boundary and a constant mass flow rate boundary, are used to assess the effects of the inlet boundary. As mass flow rate is increased, the total pressure boundary causes more error in the axial pressure distribution while the constant mass flow rate gives a better solution for all cases ran. The simulations confirm experimental findings, and reproduce qualitative as well as some of the quantitative trends. These results demonstrate that a) fuel-air mixing is highly non-uniform within the detonation chamber, leading to variations in local equivalence ratio, b) the fuel and oxidizer injectors experience significant backflow as the detonation wave passes over, but recover at different rates which further augments the inefficiencies in mixing, and c) parasitic combustion in the mixing region makes the detonation wave weak by extending the reaction zone across the wave.","PeriodicalId":365813,"journal":{"name":"Frontiers in Aerospace Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114896103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Rotating detonation combustors for propulsion: Some fundamental, numerical and experimental aspects 推进用旋转爆轰燃烧室:一些基本、数值和实验方面的问题

Frontiers in Aerospace Engineering Pub Date : 2023-03-30 DOI: 10.3389/fpace.2023.1152429

Bruno Le Naour, D. Davidenko, T. Gaillard, P. Vidal

{"title":"Rotating detonation combustors for propulsion: Some fundamental, numerical and experimental aspects","authors":"Bruno Le Naour, D. Davidenko, T. Gaillard, P. Vidal","doi":"10.3389/fpace.2023.1152429","DOIUrl":"https://doi.org/10.3389/fpace.2023.1152429","url":null,"abstract":"Propulsion systems based on the constant-pressure combustion process have reached maturity in terms of performance, which is close to its theoretical limit. Technological breakthroughs are needed to develop more efficient transportation systems that meet today’s demands for reduced environmental impact and increased performance. The Rotating Detonation Engine (RDE), a specific implementation of the detonation process, appears today as a promising candidate due to its high thermal efficiency, wide operating Mach range, short combustion time and, thus, high compactness. Following the first proofs of concept presented in the 1960s, the last decade has seen a significant increase in laboratory demonstrators with different fuels, injection techniques, operating conditions, dimensions and geometric configurations. Recently, two flight tests of rocket-type RDEs have been reported in Japan and Poland, supervized by Professors Kasahara (Nagoya University) and Wolanski (Warsaw University), respectively. Engineering approaches are now required to design industrial systems whose missions impose efficiency and reliability constraints. The latter may render ineffective the simplified solutions and configurations developed under laboratory conditions. This requires understanding the fundamentals of detonation dynamics relevant to the RDE and the interrelated optimizations of the device components. This article summarizes some of the authors’ experimental and numerical work on fundamental and applied issues now considered to affect, individually or in combination, the efficiency and reliability of the RDE. These are the structure of the detonation reaction zone, the detonation dynamics for rotating regimes, the injection configurations, the chamber geometry, and the integration constraints.","PeriodicalId":365813,"journal":{"name":"Frontiers in Aerospace Engineering","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128750613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A formulation of industrial conceptual design optimization problem for commercial transport airplanes with turboelectric propulsion 采用涡轮电力推进的商用运输机工业概念设计优化问题的表述

Frontiers in Aerospace Engineering Pub Date : 2023-03-10 DOI: 10.3389/fpace.2023.1113646

Hikaru Takami, S. Obayashi

引用次数: 0

Evaluation of a computational strategy to model transitory injection in rotating detonation combustors 旋转爆轰燃烧室瞬态喷射模型的计算策略评价

Frontiers in Aerospace Engineering Pub Date : 2023-02-23 DOI: 10.3389/fpace.2023.1127671

Pierre Hellard, T. Gaillard, D. Davidenko

{"title":"Evaluation of a computational strategy to model transitory injection in rotating detonation combustors","authors":"Pierre Hellard, T. Gaillard, D. Davidenko","doi":"10.3389/fpace.2023.1127671","DOIUrl":"https://doi.org/10.3389/fpace.2023.1127671","url":null,"abstract":"The efficiency of a Rotating Detonation Combustor (RDC) strongly depends on the transitory injection process of fresh reactants in the combustion chamber: poor propellant mixing induces losses of combustion efficiency and consequently low detonation speed and unstable detonation propagation. Moreover, dilution of fresh reactants with burnt gases during injection increases the deflagration losses and decreases the pressure gain provided by the detonation. Numerical simulation can help design an efficient injector to reduce these losses. In this study, the modeling strategy previously proposed by ONERA to simulate the transitory injection process is applied to two existing experimental RDC (from Nagoya University and TU Berlin) and one in-development RDC from ONERA. The computational domain represents only one injection element, convenient for a parametric study at low computational cost. A custom initial condition is used to model the expansion process of burnt gases past a detonation wave. The initial condition parameters are discussed and a method is proposed to correctly set them. The TU Berlin RDC is studied in more detail: mixing efficiency up to 70% is obtained, and 5% of deflagration losses are estimated according to the assumptions of the simulation. Based on the numerical results, detonation speed was evaluated at various distances from the injection plane taking into account the heterogeneities of the fresh mixture. The measured speed lies within the predicted range.","PeriodicalId":365813,"journal":{"name":"Frontiers in Aerospace Engineering","volume":"260 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132327933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A multi-fidelity model management framework for multi-objective aerospace design optimisation 面向多目标航天设计优化的多保真度模型管理框架

Frontiers in Aerospace Engineering Pub Date : 2023-02-07 DOI: 10.3389/fpace.2023.1046177

Ben Parsonage, C. Maddock

{"title":"A multi-fidelity model management framework for multi-objective aerospace design optimisation","authors":"Ben Parsonage, C. Maddock","doi":"10.3389/fpace.2023.1046177","DOIUrl":"https://doi.org/10.3389/fpace.2023.1046177","url":null,"abstract":"This paper presents a multi-fidelity meta-modelling and model management framework designed to efficiently incorporate increased levels of simulation fidelity from multiple, competing sources into early-stage multidisciplinary design optimisation scenarios. Phase specific/invariant low-fidelity physics-based subsystem models are adaptively corrected via iterative sampling of high(er)-fidelity simulators. The correction process is decomposed into several distinct parametric/non-parametric stages, each leveraging alternate aspects of the available model responses. Globally approximating surrogates are constructed at each degree of fidelity (low, mid, and high) via an automated hyper-parameter selection and training procedure. The resulting hierarchy drives the optimisation process, with local refinement managed according to a confidence-based multi-response adaptive sampling procedure, with bias given to global parameter sensitivities. An application of this approach is demonstrated via the aerodynamic response prediction of a parametrized re-entry vehicle, subjected to a static/dynamic parameter optimisation for three separate single-objective problems. It is found that the proposed data correction process facilitates increased efficiency in attaining a desired approximation accuracy relative to a single-fidelity equivalent model. When applied within the proposed multi-fidelity management framework, clear convergence to the objective optimum is observed for each examined design optimisation scenario, outperforming an equivalent single-fidelity approach in terms of computational efficiency and solution variability.","PeriodicalId":365813,"journal":{"name":"Frontiers in Aerospace Engineering","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132287867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Hybrid A* path search with resource constraints and dynamic obstacles 具有资源约束和动态障碍的混合A*路径搜索

Frontiers in Aerospace Engineering Pub Date : 2023-01-25 DOI: 10.3389/fpace.2022.1076271

Alan C. Cortez, Bryce T. Ford, I. Nayak, S. Narayanan, Mrinal Kumar

{"title":"Hybrid A* path search with resource constraints and dynamic obstacles","authors":"Alan C. Cortez, Bryce T. Ford, I. Nayak, S. Narayanan, Mrinal Kumar","doi":"10.3389/fpace.2022.1076271","DOIUrl":"https://doi.org/10.3389/fpace.2022.1076271","url":null,"abstract":"This paper considers path planning with resource constraints and dynamic obstacles for an unmanned aerial vehicle (UAV), modeled as a Dubins agent. Incorporating these complex constraints at the guidance stage expands the scope of operations of UAVs in challenging environments containing path-dependent integral constraints and time-varying obstacles. Path-dependent integral constraints, also known as resource constraints, can occur when the UAV is subject to a hazardous environment that exposes it to cumulative damage over its traversed path. The noise penalty function was selected as the resource constraint for this study, which was modeled as a path integral that exerts a path-dependent load on the UAV, stipulated to not exceed an upper bound. Weather phenomena such as storms, turbulence and ice are modeled as dynamic obstacles. In this paper, ice data from the Aviation Weather Service is employed to create training data sets for learning the dynamics of ice phenomena. Dynamic mode decomposition (DMD) is used to learn and forecast the evolution of ice conditions at flight level. This approach is presented as a computationally scalable means of propagating obstacle dynamics. The reduced order DMD representation of time-varying ice obstacles is integrated with a recently developed backtracking hybrid A∗ graph search algorithm. The backtracking mechanism allows us to determine a feasible path in a computationally scalable manner in the presence of resource constraints. Illustrative numerical results are presented to demonstrate the effectiveness of the proposed path-planning method.","PeriodicalId":365813,"journal":{"name":"Frontiers in Aerospace Engineering","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122529760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Negotiation of the global grid inspection UAV with random delay uncertainty in an information communication network based on a robust fault tolerance mechanism 基于鲁棒容错机制的随机时延不确定性全局网格检测无人机信息通信网络协商

Frontiers in Aerospace Engineering Pub Date : 2023-01-12 DOI: 10.3389/fpace.2022.978261

Jie Shen, Wenqing Dong, Zhi-fang Wang, Jing Wang, Yang Wang, Hanming Liu, Haiyan Li

{"title":"Negotiation of the global grid inspection UAV with random delay uncertainty in an information communication network based on a robust fault tolerance mechanism","authors":"Jie Shen, Wenqing Dong, Zhi-fang Wang, Jing Wang, Yang Wang, Hanming Liu, Haiyan Li","doi":"10.3389/fpace.2022.978261","DOIUrl":"https://doi.org/10.3389/fpace.2022.978261","url":null,"abstract":"To accurately simulate the interference mechanism of information communication between unmanned aerial vehicles (UAVs) in the future global grid system, a type of control based on dynamic simulation of the satellite communication network and robust fault tolerance with a stochastic delay uncertain network system is proposed. Based on the imaginary future of the global energy Internet, with unknown information and communication interference, we established a UAV model from sensor to actuator network delay using a robust, fault-tolerant control algorithm and a satellite communication network model that combined the controller’s mathematical model. The simulation results showed improved power transmission capability and communication coverage ability of UAVs by using the network fault-tolerant control mechanism with uncertain network delay and information communication interference. The stability and anti-interference performance was also significantly improved. This algorithm provides a strategy for the future development of global energy Internet.","PeriodicalId":365813,"journal":{"name":"Frontiers in Aerospace Engineering","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121070864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fluid and combustion dynamics in dual-mode scramjets 双模超燃冲压发动机的流体和燃烧动力学

Frontiers in Aerospace Engineering Pub Date : 2023-01-05 DOI: 10.3389/fpace.2022.1058038

G. Lee, Tonghun Lee

引用次数: 0

Exploring online and offline explainability in deep reinforcement learning for aircraft separation assurance 探索飞机分离保障中深度强化学习的在线和离线可解释性

Frontiers in Aerospace Engineering Pub Date : 2022-12-13 DOI: 10.3389/fpace.2022.1071793

Wei Guo, Yi Zhou, Peng Wei

{"title":"Exploring online and offline explainability in deep reinforcement learning for aircraft separation assurance","authors":"Wei Guo, Yi Zhou, Peng Wei","doi":"10.3389/fpace.2022.1071793","DOIUrl":"https://doi.org/10.3389/fpace.2022.1071793","url":null,"abstract":"Deep Reinforcement Learning (DRL) has demonstrated promising performance in maintaining safe separation among aircraft. In this work, we focus on a specific engineering application of aircraft separation assurance in structured airspace with high-density air traffic. In spite of the scalable performance, the non-transparent decision-making processes of DRL hinders human users from building trust in such learning-based decision making tool. In order to build a trustworthy DRL-based aircraft separation assurance system, we propose a novel framework to provide stepwise explanations of DRL policies for human users. Based on the different needs of human users, our framework integrates 1) a Soft Decision Tree (SDT) as an online explanation provider to display critical information for human operators in real-time; and 2) a saliency method, Linearly Estimated Gradient (LEG), as an offline explanation tool for certification agencies to conduct more comprehensive verification time or post-event analyses. Corresponding visualization methods are proposed to illustrate the information in the SDT and LEG efficiently: 1) Online explanations are visualized with tree plots and trajectory plots; 2) Offline explanations are visualized with saliency maps and position maps. In the BlueSky air traffic simulator, we evaluate the effectiveness of our framework on case studies with complex airspace route structures. Results show that the proposed framework can provide reasonable explanations of multi-agent sequential decision-making. In addition, for more predictable and trustworthy DRL models, we investigate two specific patterns that DRL policies follow based on similar aircraft locations in the airspace.","PeriodicalId":365813,"journal":{"name":"Frontiers in Aerospace Engineering","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133743679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0