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Assessment of Flyby Methods as Applied to Close Encounters among Asteroids 应用于小行星近距离相遇的飞越方法评估
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-08-09 DOI: 10.3390/aerospace11080647
N. Stronati, M. Fenucci, Marco Micheli, Marta Ceccaroni
Orbital flybys have been extensively studied for spacecraft missions, resulting in effective mathematical and physical models. However, these models’ applicability to natural encounters involving asteroids has not been explored. This paper examines the applicability of two such theories, patched conics (PC) and the Keplerian map (KM), to asteroid encounters. A review of the two methods will be provided, highlighting their assumptions and range of applicability. Simulations of asteroid–asteroid encounters will then be performed to evaluate their effectiveness in these scenarios. The simulation parameters are set by collecting data on actual asteroid–asteroid encounters, hereby presented, generally characterised by high close approach distances and small masses of the perturbing bodies, if compared to those used to build the flyby theories. Results show that the PC theory’s effectiveness diminishes with increasing approach distances, aligning with its assumptions. Moreover, the prediction of the model is better in the geometric configurations where the flyby has major effects on the orbital energy change. The KM theory has shown good effectiveness for encounters occurring outside the sphere of influence of the perturbing body, even for very high distances. This research investigates flyby models’ strengths and weaknesses in asteroid encounters, offering practical insights and future directions.
对航天器飞行任务的轨道飞越进行了广泛的研究,形成了有效的数学和物理模型。然而,这些模型对涉及小行星的自然遭遇的适用性尚未得到探讨。本文研究了两种此类理论--补间圆锥(PC)和开普勒图(KM)--对小行星遭遇的适用性。本文将对这两种方法进行回顾,重点介绍它们的假设条件和适用范围。然后将对小行星与小行星相遇进行模拟,以评估这两种方法在这些情况下的有效性。模拟参数是通过收集实际小行星与天体相遇的数据来设定的。与用于建立飞越理论的数据相比,这些数据通常具有近距离大、扰动天体质量小的特点。结果表明,PC 理论的有效性随着接近距离的增加而减弱,这与其假设相符。此外,在飞越对轨道能量变化有重大影响的几何构型中,该模型的预测效果更好。KM 理论对发生在扰动天体影响范围之外的相遇显示出良好的有效性,即使是在很远的距离上。这项研究探讨了小行星遭遇时飞越模型的优缺点,提供了实用见解和未来方向。
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引用次数: 0
On the Exploration of Temporal Fusion Transformers for Anomaly Detection with Multivariate Aviation Time-Series Data 关于利用多变量航空时间序列数据进行异常检测的时态融合变换器探索
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-08-09 DOI: 10.3390/aerospace11080646
Bulent Ayhan, Erik P. Vargo, Huang Tang
In this work, we explored the feasibility of using a transformer-based time-series forecasting architecture, known as the Temporal Fusion Transformer (TFT), for anomaly detection using threaded track data from the MITRE Corporation’s Transportation Data Platform (TDP) and digital flight data. The TFT architecture has the flexibility to include both time-varying multivariate data and categorical data from multimodal data sources and conduct single-output or multi-output predictions. For anomaly detection, rather than training a TFT model to predict the outcomes of specific aviation safety events, we train a TFT model to learn nominal behavior. Any significant deviation of the TFT model’s future horizon forecast for the output flight parameters of interest from the observed time-series data is considered an anomaly when conducting evaluations. For proof-of-concept demonstrations, we used an unstable approach (UA) as the anomaly event. This type of anomaly detection approach with nominal behavior learning can be used to develop flight analytics to identify emerging safety hazards in historical flight data and has the potential to be used as an on-board early warning system to assist pilots during flight.
在这项工作中,我们利用 MITRE 公司运输数据平台 (TDP) 的线程轨迹数据和数字飞行数据,探索了使用基于变压器的时间序列预测架构(称为时态融合变压器 (TFT))进行异常检测的可行性。TFT 架构具有灵活性,既可包含时变多变量数据,也可包含来自多模态数据源的分类数据,并可进行单输出或多输出预测。对于异常检测,我们不是训练 TFT 模型来预测特定航空安全事件的结果,而是训练 TFT 模型来学习名义行为。在进行评估时,TFT 模型对相关输出飞行参数的未来预测与观察到的时间序列数据之间的任何重大偏差都会被视为异常。在概念验证演示中,我们使用不稳定方法 (UA) 作为异常事件。这种带有标称行为学习的异常检测方法可用于开发飞行分析,以识别历史飞行数据中新出现的安全隐患,并有可能用作机载预警系统,在飞行过程中为飞行员提供帮助。
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引用次数: 0
A Multi-Objective Dynamic Mission-Scheduling Algorithm Considering Perturbations for Earth Observation Satellites 考虑扰动的地球观测卫星多目标动态任务调度算法
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-08-08 DOI: 10.3390/aerospace11080643
Hai Li, Yongjun Li, Yuanhao Liu, Kai Zhang, Xin Li, Yu Li, Shanghong Zhao
The number of real-time dynamic satellite observation missions has been rapidly increasing recently, while little attention has been paid to the dynamic mission-scheduling problem. It is crucial to reduce perturbations to the initial scheduling plan for the dynamic mission-scheduling as the perturbations have a significant impact on the stability of the Earth observation satellites (EOSs). In this paper, we focus on the EOS dynamic mission-scheduling problem, where the observation profit and perturbation are considered simultaneously. A multi-objective dynamic mission-scheduling mathematical model is first formulated. Then, we propose a multi-objective dynamic mission-scheduling algorithm (MODMSA) based on the improved Strength Pareto Evolutionary Algorithm (SPEA2). In the MODMSA, a novel two-stage individual representation, a minimum perturbation random initialization, multi-point crossover, and greedy mutation are designed to expand the search scope and improve the search efficiency. In addition, a profit-oriented local search algorithm is introduced into the SPEA2 to improve the convergence speed. Furthermore, an adaptive perturbation control strategy is adopted to improve the diversity of non−dominated solutions. Extensive experiments are conducted to evaluate the performance of the MODMSA. The simulation results show that the MODMSA outperforms other comparison algorithms in terms of solution quality and diversity, which demonstrates that the MODMSA is promising for practical EOS systems.
近来,实时动态卫星观测任务的数量迅速增加,而动态任务调度问题却鲜有人关注。由于扰动对地球观测卫星(EOS)的稳定性有重大影响,因此减少对动态任务调度初始调度计划的扰动至关重要。在本文中,我们将重点研究同时考虑观测收益和扰动的地球观测卫星动态任务调度问题。首先建立了一个多目标动态任务调度数学模型。然后,我们提出了一种基于改进强度帕累托进化算法(SPEA2)的多目标动态任务调度算法(MODMSA)。在 MODMSA 中,设计了新颖的两阶段个体表示、最小扰动随机初始化、多点交叉和贪婪突变,以扩大搜索范围并提高搜索效率。此外,SPEA2 还引入了以利润为导向的局部搜索算法,以提高收敛速度。此外,还采用了自适应扰动控制策略来提高非主导解的多样性。为了评估 MODMSA 的性能,我们进行了大量实验。仿真结果表明,MODMSA在解的质量和多样性方面优于其他比较算法,这表明MODMSA在实际EOS系统中大有可为。
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引用次数: 0
Number of Blades’ Influence on the Performance of Rotor with Equal Solidity in Open and Shrouded Configurations: Experimental Analysis 桨叶数量对开放式和笼罩式等实心转子性能的影响:实验分析
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-08-08 DOI: 10.3390/aerospace11080644
Abdallah Dayhoum, Alejandro Ramirez-Serrano, Robert Martinuzzi
This study explores the implications of the number of blades on the performance of both open and shrouded rotors. By conducting a thorough experimental analysis at a fixed solidity ratio, this research seeks to enhance our understanding of rotor dynamics and efficiency. Two-, three-, four-, and five-bladed rotors were designed and manufactured to have the same solidity ratio. This leads to smaller chord distribution values for higher blade numbers. The experimental analysis aims to quantify the effects of the number of blades and provides a comparative analysis of performance differences between the two rotor configurations (shrouded and open). For the open rotor, results indicate that increasing the number of blades has a minimal impact on overall performance. This is due to the decrease in the tip loss factor being counterbalanced by a decline in efficiency caused by the two-dimensional airfoil performance, which results from a smaller chord and a lower Reynolds number. In contrast, the shrouded rotor exhibits a noticeable performance decay with an increased blade count. Since tip loss is inherently absent in shrouded designs, the decline is primarily attributed to the two-dimensional airfoil performance. This decay occurs while maintaining a constant solidity ratio, highlighting the significant effect of blade count on shrouded rotor efficiency, thereby contributing to the optimization of rotor design in various engineering applications.
本研究探讨了叶片数量对开放式和带罩转子性能的影响。通过在固定的固体比率下进行全面的实验分析,本研究旨在加深我们对转子动力学和效率的理解。设计和制造的两叶、三叶、四叶和五叶转子具有相同的坚固比。这导致叶片数越多,弦分布值越小。实验分析旨在量化叶片数量的影响,并对两种转子配置(护罩式和开放式)之间的性能差异进行比较分析。对于开放式转子,结果表明增加叶片数量对整体性能的影响很小。这是由于叶尖损失因数的减少被二维机翼性能造成的效率下降所抵消,二维机翼性能是由较小的弦长和较低的雷诺数造成的。与此相反,随着叶片数量的增加,护罩式转子表现出明显的性能衰减。由于护罩式设计本身不存在叶尖损失,因此性能下降主要归因于二维机翼性能。这种衰减是在保持固体比不变的情况下发生的,凸显了叶片数对护罩式转子效率的显著影响,从而有助于优化各种工程应用中的转子设计。
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引用次数: 0
Numerical Study on Far-Field Noise Characteristic Generated by Wall-Mounted Swept Finite-Span Airfoil within Transonic Flow 壁挂式横扫有限跨度翼面在跨音速气流中产生的远场噪声特性的数值研究
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-08-08 DOI: 10.3390/aerospace11080645
Runpei Jiang, Peiqing Liu, Jin Zhang, Hao Guo
This study seeks to develop a fundamental comprehension of the noise challenges encountered by commercial aircraft fuselage surface attachments, such as blade antennas and pitot tubes. The study examines the flow characteristics and far-field noise directivity of a wall-mounted NACA0012 airfoil with various sweep angles (−35°, −15°, 0°, +15°, and +35°) and an aspect ratio of 1.5. The Mach numbers of the incoming flow range from 0.8 to 0.9 with a Reynolds number of about 7 × 105. Delayed Detached Eddy Simulation (DDES) and the Ffowcs Williams–Hawkings (FW-H) equation are utilized. The results show that the shock wave intensity at the junction between the airfoil and the bottom wall is enhanced by the forward-swept angle. The shock wave moves and changes into a λ-type structure, while the boundary layer separates and produces shedding vortices in the junction at a smaller Mach number on the forward-swept airfoil compared to the straight airfoil and the backward-swept airfoil. These phenomena cause significant surface pressure fluctuations in the junction and result in a significant dipole noise in the far field, which is the primary source of noise in the far field. In addition, the normal Mach number and the absolute sweep angle also contribute to the far-field noise.
本研究旨在从根本上了解商用飞机机身表面附件(如叶片天线和皮托管)所遇到的噪声挑战。该研究考察了具有不同扫描角度(-35°、-15°、0°、+15°和+35°)和长宽比为 1.5 的壁装 NACA0012 翼面的流动特性和远场噪声指向性。流入气流的马赫数在 0.8 到 0.9 之间,雷诺数约为 7 × 105。采用了延迟分离涡模拟(DDES)和 Ffowcs Williams-Hawkings (FW-H) 方程。结果表明,机翼与底壁交界处的冲击波强度因前掠角而增强。与直机翼和后掠机翼相比,前掠机翼的马赫数较小,冲击波移动并转变为 λ 型结构,同时边界层分离并在交界处产生脱落漩涡。这些现象会在交界处造成明显的表面压力波动,导致远场出现明显的偶极噪声,这也是远场噪声的主要来源。此外,法向马赫数和绝对后掠角也会对远场噪声产生影响。
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引用次数: 0
Advancing the Diagnosis of Aero-Engine Bearing Faults with Rotational Spectrum and Scale-Aware Robust Network 利用旋转频谱和规模感知鲁棒网络推进航空发动机轴承故障诊断
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-07-26 DOI: 10.3390/aerospace11080613
Jin Li, Zhengbing Yang, Xiang Zhou, Chenchen Song, Yafeng Wu
The precise monitoring of bearings is crucial for the timely detection of issues in rotating mechanical systems. However, the high complexity of the structures makes the paths of vibration signal transmission exceedingly intricate, posing significant challenges in diagnosing aero-engine bearing faults. Therefore, a Rotational-Spectrum-informed Scale-aware Robustness (RSSR) neural network is proposed in this study to address intricate fault characteristics and significant noise interference. The RSSR algorithm amalgamates a scale-aware feature extraction block, a non-activation convolutional network, and an innovative channel attention block, striking a balance between simplicity and efficacy. We provide a comprehensive analysis by comparing traditional CNNs, transformers, and their respective variants. Our strategy not only elevates diagnostic precision but also judiciously moderates the network’s parameter count and computational intensity, mitigating the propensity for overfitting. To assess the efficacy of our proposed network, we performed rigorous testing using two complex, publicly available datasets, with additional artificial noise introductions to simulate challenging operational environments. On the noise-free dataset, our technique increased the accuracy by 5.11% on the aero-engine dataset compared with the current mainstream methods. Even under maximal noise conditions, it enhances the average accuracy by 4.49% compared with other contemporary approaches. The results demonstrate that our approach outperforms other techniques in terms of diagnostic performance and generalization ability.
精确监测轴承对于及时发现旋转机械系统中的问题至关重要。然而,由于结构的高度复杂性,振动信号的传输路径错综复杂,给航空发动机轴承故障诊断带来了巨大挑战。因此,本研究提出了一种以旋转频谱为基础的规模感知鲁棒性(RSSR)神经网络,以解决错综复杂的故障特征和严重的噪声干扰问题。RSSR 算法融合了规模感知特征提取模块、非激活卷积网络和创新的通道注意模块,在简单性和有效性之间取得了平衡。我们通过比较传统的 CNN、变换器及其各自的变体进行了全面分析。我们的策略不仅提高了诊断精度,还明智地调节了网络的参数数量和计算强度,减轻了过度拟合的倾向。为了评估我们提出的网络的功效,我们使用两个复杂的公开数据集进行了严格的测试,并引入了额外的人工噪音来模拟具有挑战性的操作环境。在无噪声数据集上,与目前的主流方法相比,我们的技术在航空发动机数据集上的准确率提高了 5.11%。即使在最大噪声条件下,与其他当代方法相比,我们的平均准确率也提高了 4.49%。结果表明,我们的方法在诊断性能和泛化能力方面优于其他技术。
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引用次数: 0
Twist Angle Error Statistical Analysis and Uncertain Influence on Aerodynamic Performance of Three-Dimensional Compressor Rotor 扭转角误差统计分析及对三维压缩机转子气动性能的不确定影响
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-07-26 DOI: 10.3390/aerospace11080614
Yue Dan, Ruiyu Li, Limin Gao, Huawei Yu, Yuyang Hao
Twist angle errors along the blade radial direction are uncertain and affected by cutting force, tool wear, and other factors. In this paper, the measured twist angle errors of 13 sections of 72 rotor blades were innovatively analyzed to obtain the rational statistical distribution. It is surprisingly found that the under-deflection systematic deviation of twist angle errors shows a gradually increasing W-shaped distribution along the radial direction, while the scatter is nearly linear. Logically, the statistical model is established based on the linear correlation of the scatter by regression analysis to reduce variable dimension from 13 to 1. The influence of the radial non-uniform twist angle errors’ uncertainty on the aerodynamic performance of the three-dimensional compressor rotor is efficiently quantified combining the non-intrusive polynomial chaos method. The results show that the mean values of mass flow rate, total pressure ratio, and isentropic efficiency at the typical operating conditions are lower than the nominal values due to the systematic deviation, indicating that the under-deflection twist angle errors lead to the decrease in compressor thrust. The compressor’s stable operating range is more sensitive to the scatter of twist angle errors, which is up to an order of magnitude greater than that of the total pressure ratio and isentropic efficiency, indicating the compressor’s safe and stable operation risk increases. Additionally, the flow field at the tip region is significantly affected by twist angle errors, especially at the shock wave position of the near-stall condition.
沿叶片径向的扭转角误差是不确定的,并受到切削力、刀具磨损和其他因素的影响。本文对 72 个转子叶片的 13 个截面的扭转角误差测量值进行了创新性分析,以获得合理的统计分布。结果令人惊讶地发现,扭转角误差的欠偏系统偏差沿径向呈逐渐增大的 "W "形分布,而散点近似线性。结合非侵入式多项式混沌方法,有效量化了径向非均匀扭转角误差不确定性对三维压缩机转子气动性能的影响。结果表明,由于系统偏差的存在,典型工况下的质量流量、总压比和等熵效率的平均值均低于标称值,这表明挠度不足的扭转角误差导致了压缩机推力的下降。压缩机的稳定运行范围对扭转角误差的散度更为敏感,其散度比总压比和等熵效率的散度大一个数量级,表明压缩机安全稳定运行的风险增加。此外,尖端区域的流场受扭转角误差的影响很大,尤其是在近滞流工况的冲击波位置。
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引用次数: 0
Leader-Following Connectivity Preservation and Collision Avoidance Control for Multiple Spacecraft with Bounded Actuation 多航天器的 "领航-跟随 "连接性保持和碰撞规避控制
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-07-26 DOI: 10.3390/aerospace11080612
Xianghong Xue, Xin Wang, Nannan Han
This paper investigates the distributed formation control of a group of leader-following spacecraft with bounded actuation and limited communication ranges. In particular, connectivity-preserving and collision-avoidance controllers are proposed for the leader with constant or time-varying velocity, respectively. The communication graph between the spacecraft is modeled via a distance-induced proximity graph. By designing a virtual proxy for each spacecraft, the spacecraft–proxy couplings address the actuator saturation constraints. The inter-proxy dynamics incorporated with a bounded artificial potential function fulfill the coordination of all proxies. In addition, the bounded potential function can simultaneously tackle connectivity preservation and collision avoidance problems. The distributed formation controllers are proposed for multiple spacecraft with constant or time-varying velocities relative to the leader. A sliding mode control approach and the proxies’ dynamics are used in the design of a distributed cooperative controller for spacecraft to address the cooperative problem between the followers and the leader. Numerical simulations confirm the effectiveness of the anti-saturation distributed connectivity preservation controller.
本文研究了一组领航者-跟随者航天器的分布式编队控制,这些航天器具有有界的驱动力和有限的通信范围。特别是,针对速度恒定或时变的领航者,分别提出了连通性保护控制器和避免碰撞控制器。航天器之间的通信图是通过距离引起的邻近图建模的。通过为每个航天器设计一个虚拟代理,航天器-代理耦合解决了致动器饱和约束。代理之间的动态与有界人工势函数相结合,实现了所有代理之间的协调。此外,有界势函数还能同时解决连通性保持和避免碰撞问题。针对相对于领导者速度恒定或时变的多个航天器,提出了分布式编队控制器。在设计航天器的分布式合作控制器时,采用了滑模控制方法和代理动力学,以解决跟随者和领导者之间的合作问题。数值模拟证实了抗饱和分布式连通性保护控制器的有效性。
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引用次数: 0
Analysis and Evaluation of Fault Propagation Behavior in Integrated Avionics Systems Considering Cascading Failures 考虑级联故障的集成航空电子系统故障传播行为分析与评估
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-07-25 DOI: 10.3390/aerospace11080608
Lei Dong, Bo Peng, Xi Chen, Jiachen Liu
As the synthesis, modularization, and integration of avionics systems increase, the interconnections between systems and equipment within subsystems become increasingly complex, posing risks to the safety and reliability of the integrated avionics system. To address the risk of fault propagation due to functional cascade failures in integrated avionics systems, this paper proposes a discrete dynamic fault propagation analysis method, which was applied to an all-electric braking system to assess its feasibility. First, the architectural features of the Distributed Integrated Modular Avionics system are summarized. Subsequently, the constructed system layer model is described, establishing the function–resource hierarchical architecture. Subsequently, the behavior of cascading failure propagation in discrete dynamic systems is analyzed by integrating the cascading failure analysis method from SAE ARP 4761A and considering the coupling characteristics between system properties and functions comprehensively. This approach facilitates the development of a cascading failure propagation model for DIMA based on discrete dynamic systems. Finally, by using the all-electric braking system under DIMA architecture as a case study, key Core Processing Modules and failure-prone functions are identified. The findings reveal that within this system, CPM2 and CPM6 are particularly susceptible to failure propagation, and the automatic brake function is notably vulnerable. Data show that the system’s failure rate escalates markedly after 2×104 h of operation. Performing maintenance before reaching this threshold can further mitigate risks. This practice aligns with current international aircraft maintenance time regulations. The method proposed in this paper can be applied early in the allocation of DIMA resources to enhance security and support DIMA design.
随着航空电子系统综合化、模块化和集成化程度的提高,系统之间以及子系统内部设备之间的相互联系变得越来越复杂,给集成航空电子系统的安全性和可靠性带来了风险。针对集成航电系统中功能级联故障导致的故障传播风险,本文提出了一种离散动态故障传播分析方法,并将其应用于全电制动系统以评估其可行性。首先,总结了分布式集成模块化航空电子系统的架构特点。随后,描述了构建的系统层模型,建立了功能-资源分层架构。随后,结合 SAE ARP 4761A 中的级联故障分析方法,综合考虑系统属性与功能之间的耦合特性,分析了离散动态系统中的级联故障传播行为。这种方法有助于开发基于离散动态系统的 DIMA 级联故障传播模型。最后,以 DIMA 架构下的全电动制动系统为例,确定了关键核心处理模块和易失效功能。研究结果表明,在该系统中,CPM2 和 CPM6 特别容易受到故障传播的影响,而自动制动功能尤其脆弱。数据显示,系统运行 2×104 小时后,故障率明显上升。在达到这个临界值之前进行维护可以进一步降低风险。这种做法符合现行的国际飞机维护时间规定。本文提出的方法可用于 DIMA 资源分配的早期阶段,以提高安全性并支持 DIMA 设计。
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引用次数: 0
Fuzzy Control for Aircraft Engine: Dynamics Clustering Modeling, Compensation and Hardware-in-Loop Experimental Verification 飞机发动机模糊控制:动态聚类建模、补偿和硬件在环实验验证
IF 2.1 3区 工程技术 Q2 ENGINEERING, AEROSPACE Pub Date : 2024-07-25 DOI: 10.3390/aerospace11080610
Muxuan Pan, Hao Wang, Chenchen Zhang, Yun Xu
This paper presents an integrated framework for aircraft engines, which consists of three phases: modeling, control, and experimental testing. The engine is formulated as an uncertain T–S fuzzy model. By a hierarchical dynamical parameter clustering, the number and premise variables of fuzzy rules are optimized, which keeps the engine’s prime and representative dynamics. For each fuzzy rule, a global stability-guaranteed method is developed for the identification of the consequent uncertain dynamic model. The resulting stable T–S fuzzy model accurately approximates the actual engine dynamics in the operation space. Based on this fuzzy model, a new robust control is constructed with hierarchical compensators. The control parameters take advantage of the fuzzy blend of engine prime dynamics and uncertainty thresholds. Extensive hardware-in-loop (HIL) experimental tests in the flight envelope and a flight task cycle demonstrate the effectiveness and real-time performance of the proposed control. The settling times and overshoots of engine response are suppressed to be under 2.5 s and 10%, respectively.
本文介绍了飞机发动机的集成框架,包括建模、控制和实验测试三个阶段。发动机被表述为一个不确定的 T-S 模糊模型。通过分层动态参数聚类,优化了模糊规则的数量和前提变量,从而保持了发动机的原动力和代表性。针对每个模糊规则,开发了一种全局稳定性保证方法,用于识别相应的不确定动态模型。由此产生的稳定 T-S 模糊模型准确地逼近了发动机在运行空间中的实际动态。在此模糊模型的基础上,利用分层补偿器构建了一种新的鲁棒控制。控制参数利用了发动机原动力和不确定性阈值的模糊混合。在飞行包络线和飞行任务循环中进行的大量硬件在环(HIL)实验测试证明了所建议控制的有效性和实时性。发动机响应的稳定时间和过冲分别被抑制在 2.5 秒和 10%以下。
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引用次数: 0
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Aerospace
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