Next Issue
Volume 12, October
Previous Issue
Volume 12, August
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.0
2.2
Journals
Aerospace
Volume 12
Issue 9
share announcement

Aerospace, Volume 12, Issue 9 (September 2025) – 106 articles

Cover Story (view full-size image): The safety of autonomous drones relies on Positioning, Navigation and Timing (PNT) data from Global Navigation Satellite Systems (GNSSs), which in urban and suburban environments can be degraded by multiple threats. To assess resilient GNSS-based solutions for Urban Air Mobility (UAM), this work presents the design, implementation and testing of a GNSS Threat Simulator (GTS) able to reproduce critical issues such as limited satellite visibility, multipath, interference, spoofing, jamming and satellite failures. The GTS elaborates and modifies dual-frequency multi-constellation GNSS observables in order to inject threats, and its effectiveness was proven through fast-time and real-time simulations supporting the validation of a hybrid navigation unit on a drone in a representative urban scenario. View this paper
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
28 pages, 6622 KB  
Article
Bayesian Spatio-Temporal Trajectory Prediction and Conflict Alerting in Terminal Area
by Yangyang Li, Yong Tian, Xiaoxuan Xie, Bo Zhi and Lili Wan
Aerospace 2025, 12(9), 855; https://doi.org/10.3390/aerospace12090855 - 22 Sep 2025
Viewed by 230
Abstract
Precise trajectory prediction in the airspace of a high-density terminal area (TMA) is crucial for Trajectory Based Operations (TBO), but frequent aircraft interactions and maneuvering behaviors can introduce significant uncertainties. Most existing approaches use deterministic deep learning models that lack uncertainty quantification and [...] Read more.
Precise trajectory prediction in the airspace of a high-density terminal area (TMA) is crucial for Trajectory Based Operations (TBO), but frequent aircraft interactions and maneuvering behaviors can introduce significant uncertainties. Most existing approaches use deterministic deep learning models that lack uncertainty quantification and explicit spatial awareness. To address this gap, we propose the BST-Transformer, a Bayesian spatio-temporal deep learning framework that produces probabilistic multi-step trajectory forecasts and supports probabilistic conflict alerting. The framework first extracts temporal and spatial interaction features via spatio-temporal attention encoders and then uses a Bayesian decoder with variational inference to yield trajectory distributions. Potential conflicts are evaluated by Monte Carlo sampling of the predictive distributions to produce conflict probabilities and alarm decisions. Experiments based on real SSR data from the Guangzhou TMA show that this model performs exceptionally well in improving prediction accuracy by reducing MADE 60.3% relative to a deterministic ST-Transformer with analogous reductions in horizontal and vertical errors (MADHE and MADVE), quantifying uncertainty and significantly enhancing the system’s ability to identify safety risks, and providing strong support for intelligent air traffic management with uncertainty perception capabilities. Full article
(This article belongs to the Section Air Traffic and Transportation)
►▼ Show Figures

Figure 1

21 pages, 9543 KB  
Article
Conjugate Heat Transfer and Flow Analysis of Double-Wall Cooling with Printable Gyroid-Type TPMS-Based Effusion
by Kirttayoth Yeranee, Chao Xu, Yu Rao, Yuli Cheng, Qiuru Zuo and Guodong Zhang
Aerospace 2025, 12(9), 854; https://doi.org/10.3390/aerospace12090854 - 22 Sep 2025
Viewed by 259
Abstract
This study introduces the Gyroid structure, a type of triply periodic minimal surface (TPMS), for enhanced effusion cooling performance. Conjugate heat transfer simulations are used to compare the flow behavior, pressure loss, and overall cooling effectiveness of single- and double-wall Gyroid configurations against [...] Read more.
This study introduces the Gyroid structure, a type of triply periodic minimal surface (TPMS), for enhanced effusion cooling performance. Conjugate heat transfer simulations are used to compare the flow behavior, pressure loss, and overall cooling effectiveness of single- and double-wall Gyroid configurations against a baseline film hole model at blowing ratios of 0.5–2.0. Results show that the Gyroid design eliminates jet lift-off and counter-rotating vortex pairs, ensuring full coolant coverage and a thicker coolant layer than the baseline. The double-wall configuration further improves cooling with jet impingement, yielding higher average Nusselt numbers than the single-wall design. At equal pressure loss, the impingement/Gyroid model outperforms the baseline by 102.7% in cooling effectiveness. To assess manufacturability, a high-resolution CT scan is used to validate a laser powder bed fusion-printed Gyroid sample at gas turbine blade scale, confirming feasibility for industrial application. These findings highlight the superior thermal performance and manufacturability of the 3D-printed Gyroid structure, offering a promising cooling solution for next-generation turbine blades. Full article
(This article belongs to the Section Aeronautics)
►▼ Show Figures

Figure 1

23 pages, 7843 KB  
Article
An Experimental and Numerical Comparison of the Mechanical Characteristics of a Space Inflatable Antenna Reflector Made with Kapton and Mylar Films
by Yu Hu, Rongyan Guo, Enze Qiao and Wujun Chen
Aerospace 2025, 12(9), 853; https://doi.org/10.3390/aerospace12090853 - 21 Sep 2025
Viewed by 220
Abstract
Kapton and Mylar film materials are used to manufacture space inflatable antenna reflectors; therefore, their mechanical characteristics are considered important parameters for the design of inflatable antenna reflectors. This paper mainly introduces a series of experiments on the mechanical properties of Kapton VN [...] Read more.
Kapton and Mylar film materials are used to manufacture space inflatable antenna reflectors; therefore, their mechanical characteristics are considered important parameters for the design of inflatable antenna reflectors. This paper mainly introduces a series of experiments on the mechanical properties of Kapton VN and Kapton HN, and Mylar I and II film specimens, including film tensile tests, film seam tests with tape bonding and glue bonding, and skirt edge joint tests. Therefore, failure modes, stress versus strain curves, ultimate tensile strength, and extension at break are obtained for these specimens of Kapton VN and Kapton HN and Mylar I and II films. Based on these measured data, stress conditions of models with 12 and 18 sections using ANASYS are compared to identify the effect of different sections and pressures on the force of inflatable antenna reflectors. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

33 pages, 7053 KB  
Article
Simulation Study of Gas Cooling for Aero-Engine Borescope Probes
by Lu Jia, Hao Zeng, Rui Xi, Jingbo Peng and Xinyao Hou
Aerospace 2025, 12(9), 852; https://doi.org/10.3390/aerospace12090852 - 21 Sep 2025
Viewed by 157
Abstract
After an aero-engine shuts down, the high temperature within the core flow path prevents conventional borescope probes from performing immediate internal inspections due to their limited thermal resistance, thereby constraining rapid turnaround capabilities for aircraft. To address this challenge, this study proposes an [...] Read more.
After an aero-engine shuts down, the high temperature within the core flow path prevents conventional borescope probes from performing immediate internal inspections due to their limited thermal resistance, thereby constraining rapid turnaround capabilities for aircraft. To address this challenge, this study proposes an active cooling strategy using coolant flow to keep the probe within a safe temperature range. Three cooling structures incorporating pressure-drop modules—annular, annular-slit, and round-hole configurations—were designed and numerically investigated to assess the effects of geometric parameters and coolant properties (temperature, pressure, nitrogen mixing ratio) on cooling performance. The results demonstrate that the round-hole structure with a 1.0 mm diameter achieves optimal cooling, maintaining an average probe mirror temperature of 286.2 K under coolant conditions of 285 K and 0.5 MPa. Cooling efficiency exhibits a strong linear negative correlation with coolant temperature, while its relationship with pressure is highly structure-dependent. Nitrogen doping significantly improves the heat transfer capacity of the coolant. The implemented three-stage pressure-drop module performs consistently, with the pressure loss per stage determined solely by the inlet pressure. This study provides valuable insights and a theoretical foundation for the design of high-temperature-resistant borescope equipment capable of operating in the harsh environments of aero-engines. Full article
(This article belongs to the Section Aeronautics)
►▼ Show Figures

Figure 1

13 pages, 2263 KB  
Article
Intercepting 3I/ATLAS at Its Closest Approach to Jupiter with the Juno Spacecraft
by Abraham Loeb, Adam Hibberd and Adam Crowl
Aerospace 2025, 12(9), 851; https://doi.org/10.3390/aerospace12090851 - 20 Sep 2025
Viewed by 844
Abstract
The interstellar object 3I/ATLAS is expected to arrive at a distance of 53.56(±0.45) million km (0.358±0.003 au) from Jupiter on 16 March 2026. We show that applying a total thrust ΔV of [...] Read more.
The interstellar object 3I/ATLAS is expected to arrive at a distance of 53.56(±0.45) million km (0.358±0.003 au) from Jupiter on 16 March 2026. We show that applying a total thrust ΔV of 2.6755kms−1 to the lower perijove on 9 September 2025 and then executing a Jupiter Oberth Maneuver can bring the Juno spacecraft from its orbit around Jupiter to intercept the path of 3I/ATLAS on 14 March 2026. We further show that it is possible for Juno to come much closer to 3I/ATLAS (~27 million km) with 110 kg of remaining propellant, merely 5.4% of the initial fuel reservoir. We find that for low available ΔV, there is no particular benefit in the application of a double impulse (for example, to reach ~27 million km from 3I/ATLAS); however, if Juno has a higher ΔV capability, there is a significant advantage of a second impulse, typically saving propellant by a factor of a half. A close fly-by might allow us to probe the nature of 3I/ATLAS far better than telescopes on Earth. Full article
(This article belongs to the Special Issue Spacecraft Trajectory Design)
►▼ Show Figures

Figure 1

30 pages, 3130 KB  
Article
A Generic Actuator Management Solution for Space Applications Based on Convex Optimization
by Jesús Ramírez, Joost Veenman, Ilario Cantiello and Valentin Preda
Aerospace 2025, 12(9), 850; https://doi.org/10.3390/aerospace12090850 - 20 Sep 2025
Viewed by 216
Abstract
This paper addresses a common challenge in space systems: how to effectively manage multiple actuators under demanding mission conditions. We introduce a flexible, optimization-based algorithm designed to dispatch control commands among a set of available actuators while focusing on minimizing resource usage, such [...] Read more.
This paper addresses a common challenge in space systems: how to effectively manage multiple actuators under demanding mission conditions. We introduce a flexible, optimization-based algorithm designed to dispatch control commands among a set of available actuators while focusing on minimizing resource usage, such as power and fuel. The method guarantees feasible solutions even in the presence of actuator failures, making it highly suitable for space applications. To illustrate its versatility, we show how the algorithm can be tailored to different mission scenarios with minimal effort. Several benchmark problems were implemented and tested on space-graded hardware for processor-in-the-loop verification. For this purpose, a customized solver was developed, ensuring high numerical efficiency. This paper highlights key results that demonstrate the algorithm’s practical value and mission readiness. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

19 pages, 3612 KB  
Article
Phase-Adaptive Reinforcement Learning for Self-Tuning PID Control of Cruise Missiles
by Chang Tan, Jianfeng Wang, Hong Cai, Sen Hu, Bangchu Zhang and Weiyu Zhu
Aerospace 2025, 12(9), 849; https://doi.org/10.3390/aerospace12090849 - 20 Sep 2025
Viewed by 152
Abstract
Conventional fixed-gain PID controllers face inherent limitations in maintaining optimal performance across the diverse and dynamic flight phases of cruise missiles. To overcome these challenges, we propose Time-Fusion Proximal Policy Optimization (TF-PPO), a novel adaptive reinforcement learning framework designed specifically for cruise missile [...] Read more.
Conventional fixed-gain PID controllers face inherent limitations in maintaining optimal performance across the diverse and dynamic flight phases of cruise missiles. To overcome these challenges, we propose Time-Fusion Proximal Policy Optimization (TF-PPO), a novel adaptive reinforcement learning framework designed specifically for cruise missile control. TF-PPO synergistically integrates Long Short-Term Memory (LSTM) networks for enhanced temporal state perception and phase-specific reward engineering enabling self-evolution of PID parameters. Extensive hardware-in-the-loop experiments tailored to cruise missile dynamics demonstrate that TF-PPO achieves a 36.3% improvement in control accuracy over conventional PID methods. The proposed framework provides a robust, high-precision adaptive control solution capable of enhancing the performance of cruise missile systems under varying operational. Full article
(This article belongs to the Special Issue New Perspective on Flight Guidance, Control and Dynamics)
►▼ Show Figures

Figure 1

26 pages, 3838 KB  
Article
DRL-Based UAV Autonomous Navigation and Obstacle Avoidance with LiDAR and Depth Camera Fusion
by Bangsong Lei, Wei Hu, Zhaoxu Ren and Shude Ji
Aerospace 2025, 12(9), 848; https://doi.org/10.3390/aerospace12090848 - 20 Sep 2025
Viewed by 483
Abstract
With the growing application of unmanned aerial vehicles (UAVs) in complex, stochastic environments, autonomous navigation and obstacle avoidance represent critical technical challenges requiring urgent solutions. This study proposes an innovative deep reinforcement learning (DRL) framework that leverages multimodal perception through the fusion of [...] Read more.
With the growing application of unmanned aerial vehicles (UAVs) in complex, stochastic environments, autonomous navigation and obstacle avoidance represent critical technical challenges requiring urgent solutions. This study proposes an innovative deep reinforcement learning (DRL) framework that leverages multimodal perception through the fusion of LiDAR and depth camera data. A sophisticated multi-sensor data preprocessing mechanism is designed to extract multimodal features, significantly enhancing the UAV’s situational awareness and adaptability in intricate, stochastic environments. In the high-level decision-maker of the framework, to overcome the intrinsic limitation of low sample efficiency in DRL algorithms, this study introduces an advanced decision-making algorithm, Soft Actor-Critic with Prioritization (SAC-P), which markedly accelerates model convergence and enhances training stability through optimized sample selection and utilization strategies. Validated within a high-fidelity Robot Operating System (ROS) and Gazebo simulation environment, the proposed framework achieved a task success rate of 81.23% in comparative evaluations, surpassing all baseline methods. Notably, in generalization tests conducted in previously unseen and highly complex environments, it maintained a success rate of 72.08%, confirming its robust and efficient navigation and obstacle avoidance capabilities in complex, densely cluttered environments with stochastic obstacle distributions. Full article
(This article belongs to the Section Aeronautics)
►▼ Show Figures

Figure 1

25 pages, 9674 KB  
Article
Dual-Redundancy Electric Propulsion System for Electric Helicopters Based on Extended State Observer and Master–Slave Fault-Tolerant Control
by Shuli Wang, Zhenyu Du and Qingxin Zhang
Aerospace 2025, 12(9), 847; https://doi.org/10.3390/aerospace12090847 - 19 Sep 2025
Viewed by 231
Abstract
To improve the reliability and fault tolerance of electric helicopter propulsion systems, this paper presents a master–slave fault-tolerant control method based on an extended state observer (ESO) for dual-redundant electric propulsion systems that addresses dynamic coupling disturbances. First, the control architecture puts the [...] Read more.
To improve the reliability and fault tolerance of electric helicopter propulsion systems, this paper presents a master–slave fault-tolerant control method based on an extended state observer (ESO) for dual-redundant electric propulsion systems that addresses dynamic coupling disturbances. First, the control architecture puts the master motor in speed loop mode and puts the slave motor in torque loop mode with an ESO to estimate disturbances and compensate for mechanical coupling torque through feedforward control based on Lyapunov stability theory. Second, a least squares parameter identification method establishes a current-torque mapping model to ensure consistent dual-motor output. Then, fault-tolerant switching is implemented, transitioning from normal torque mode coordination to independent speed mode with adaptive PI adjustment during faults. Experimental validation shows that the total torque stabilizes at 240 N·m, and the synchronization error remains within ±0.5 N·m during normal operation. Under single-motor fault scenarios, the ESO detects disturbances within 15 ms with >95% accuracy. The system speed decreases to a minimum of 2280 rpm (5% deviation) and recovers within 3.5 s. Compared to traditional PI control, this method improves torque synchronization by 65.4%, speed stability by 62.6%, and dynamic response by 51.2%. Finally, the results validate that the method effectively suppresses coupling interference and meets aviation safety standards, providing reliable, fault-tolerant solutions for electric helicopter propulsion. Full article
(This article belongs to the Special Issue Advanced Aircraft Technology (2nd Edition))
►▼ Show Figures

Figure 1

35 pages, 8465 KB  
Article
Momentum- and Energy-Based Analyses of the Aerodynamic Effects of Boundary Layer Ingestion and Propulsion–Airframe Integration on a Blended Wing Body–Turbofan Configuration
by Gang Wang, Dong Li, Peifeng Li and Binqian Zhang
Aerospace 2025, 12(9), 846; https://doi.org/10.3390/aerospace12090846 - 18 Sep 2025
Viewed by 238
Abstract
Boundary layer ingestion (BLI) propulsion offers notable benefits for blended wing body (BWB) aircraft, and understanding the interrelated effects of BLI and propulsion–airframe integration (PAI) is critical for early-stage design decisions. This study numerically applies combined momentum- and energy-based analyses to a closely [...] Read more.
Boundary layer ingestion (BLI) propulsion offers notable benefits for blended wing body (BWB) aircraft, and understanding the interrelated effects of BLI and propulsion–airframe integration (PAI) is critical for early-stage design decisions. This study numerically applies combined momentum- and energy-based analyses to a closely coupled but non-integrated BWB–turbofan configuration enabling a continuous transition from non-BLI to BLI conditions. By introducing an idealized capture streamtube–airframe interaction force, the drag of BLI layout is decomposed into additional and external components, enabling quantification of a lift-to-drag ratio improvement of 1.7–2.6, corresponding to a 7.14–8.27% gain in power saving coefficient (PSC). Additional drag reduction, the primary contributor to total drag savings, is analytically attributed to inlet total pressure loss. The resulting decrease in required thrust under BLI shows strong mathematical correlation with jet dissipation reduction, revealing an intrinsic link between drag reduction and power saving. PAI exerts a significant influence on the BLI benefits, including nacelle cowl drag penalties, significant variations in shock wave location and strength, and notable suppression of both boundary layer and wake dissipation for the portion of cowl immersed in the airframe wake. These findings inform the transition from podded to BLI engine layouts. Full article
(This article belongs to the Special Issue Advanced Aircraft Technology (2nd Edition))
►▼ Show Figures

Figure 1

19 pages, 6674 KB  
Article
Investigation of the Impact of an Undetected Instrument Landing System Failure on Crew Situational Awareness
by Zuzanna Lonca and Paweł Rzucidło
Aerospace 2025, 12(9), 845; https://doi.org/10.3390/aerospace12090845 - 18 Sep 2025
Viewed by 182
Abstract
This article examines the impact of an undetected Instrument Landing System (ILS) failure on crew situational awareness. A literature review of similar aviation accidents is presented, highlighting the recurring challenge of misleading instrument indications and their influence on approach safety. The research environment [...] Read more.
This article examines the impact of an undetected Instrument Landing System (ILS) failure on crew situational awareness. A literature review of similar aviation accidents is presented, highlighting the recurring challenge of misleading instrument indications and their influence on approach safety. The research environment consisted of flight simulator replicating both ideal and accident-weather conditions at two airports, with the final scenario involving a simulated ILS receiver malfunction providing erroneous yet seemingly valid indications. Six pilots with varying flight hours participated, conducting four simulated approaches under different conditions. Flight path stability, deviation from glide slope and course, approach speed, and decision-making were recorded and analyzed. The results indicate that experienced pilots detected inconsistencies more quickly, maintained more stable control inputs, and initiated go-arounds earlier, while less experienced pilots required more time but were still able to correctly assess the risks. The primary goal of this research was to identify cognitive mechanisms and operational decision-making processes under simulated conditions, not to establish universally generalizable outcomes. The findings underline the importance of simulator-based training incorporating unexpected navigation system failures to reinforce cross-checking habits, enhance situational awareness, and improve decision-making during critical phases of flight. Full article
(This article belongs to the Section Air Traffic and Transportation)
►▼ Show Figures

Figure 1

24 pages, 3359 KB  
Article
A Unified Scheduling Model for Agile Earth Observation Satellites Based on DQG and PPO
by Mengmeng Qin, Zhanpeng Xu, Xuesheng Zhao, Wenbin Sun, Wenlan Xie and Qingping Liu
Aerospace 2025, 12(9), 844; https://doi.org/10.3390/aerospace12090844 - 18 Sep 2025
Viewed by 179
Abstract
Agile Earth Observation Satellites (AEOSs), with their maneuverability, can flexibly observe point, line and region targets. However, existing research typically requires distinct algorithms for each target type, lacking a unified modeling and solution framework, which hinders the ability to meet the demands of [...] Read more.
Agile Earth Observation Satellites (AEOSs), with their maneuverability, can flexibly observe point, line and region targets. However, existing research typically requires distinct algorithms for each target type, lacking a unified modeling and solution framework, which hinders the ability to meet the demands of rapid and coordinated observation of multiple target types in complex scenarios. To address these issues, this paper proposes a unified scheduling model for agile Earth observation satellites based on the Degenerate Quadtree Grid (DQG) and Proximal Policy Optimization (PPO), termed AEOSSP-USM. Firstly, the DQG is first employed to enable unified management and integrated modeling of point, line, and area targets; Secondly, traditional time window calculations based on longitude and latitude are replaced with grid code-based computations using DQG; Finally, the PPO algorithm, a deep reinforcement learning method, is introduced to formulate AEOSSP-USM as a Markov Decision Process (MDP), enabling efficient problem solving. Experimental results demonstrate that the proposed method effectively realizes unified scheduling of heterogeneous targets, improving imaging quality about 3 times, reducing energy consumption by 10%, decreasing memory usage more than 90%, and enhancing computational efficiency by 35 times compared to conventional longitude-latitude strip algorithm. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

20 pages, 3607 KB  
Article
Addressing Calibration Challenges for Large-Stroke Blade Pitch Control in Tiltrotor Aircraft via an Improved Cubic Polynomial Fitting Algorithm
by Hang Feng, Shangyu Li, Kaicheng Li and Junquan Chen
Aerospace 2025, 12(9), 843; https://doi.org/10.3390/aerospace12090843 - 18 Sep 2025
Viewed by 191
Abstract
Tiltrotor aircraft, due to their vertical takeoff and landing capability and efficient high-speed cruise performance, are increasingly valuable in both modern military and civilian applications. However, traditional calibration methods for blade pitch control often lack the precision required for large actuator strokes, which [...] Read more.
Tiltrotor aircraft, due to their vertical takeoff and landing capability and efficient high-speed cruise performance, are increasingly valuable in both modern military and civilian applications. However, traditional calibration methods for blade pitch control often lack the precision required for large actuator strokes, which limits the control accuracy. This study aims to overcome these limitations by introducing an improved polynomial fitting algorithm to model the nonlinear relationship between the blade pitch control angles and actuator strokes. Using a specific rotor model, a coordinate system was established for the pitch control mechanism and spatial geometric relationships were derived. Experimental comparisons demonstrate that the proposed cubic polynomial fitting algorithm reduces the collective pitch error by approximately 57% and cyclic pitch error by 33%, markedly outperforming traditional linear fitting methods. These improvements significantly enhance the control precision and operational stability. The findings provide a reliable theoretical and practical basis for improving tiltrotor flight performance and safety. Full article
(This article belongs to the Special Issue Flight Dynamics, Control & Simulation (2nd Edition))
►▼ Show Figures

Figure 1

20 pages, 23718 KB  
Article
A Mamba-Based Hierarchical Partitioning Framework for Upper-Level Wind Field Reconstruction
by Wantong Chen, Yifan Zhang, Ruihua Liu, Shuguang Sun and Qing Feng
Aerospace 2025, 12(9), 842; https://doi.org/10.3390/aerospace12090842 - 18 Sep 2025
Viewed by 209
Abstract
An accurate perception of upper-level wind fields is essential for improving civil aviation safety and route optimization. However, the sparsity of observational data and the structural complexity of wind fields make reconstruction highly challenging. To address this, we propose QuadMamba-WindNet (QMW-Net), a structure-enhanced [...] Read more.
An accurate perception of upper-level wind fields is essential for improving civil aviation safety and route optimization. However, the sparsity of observational data and the structural complexity of wind fields make reconstruction highly challenging. To address this, we propose QuadMamba-WindNet (QMW-Net), a structure-enhanced deep neural network that integrates a hierarchical state-space modeling framework with a learnable quad-tree-based regional partitioning mechanism, enabling multi-scale adaptive encoding and efficient dynamic modeling. The model is trained end-to-end on ERA5 reanalysis data and validated with simulated flight trajectory observation masks, allowing the reconstruction of complete horizontal wind fields at target altitude levels. Experimental results show that QMW-Net achieves a mean absolute error (MAE) of 1.62 m/s and a mean relative error (MRE) of 6.68% for wind speed reconstruction at 300 hPa, with a mean directional error of 4.85° and an R2 of 0.93, demonstrating high accuracy and stable error convergence. Compared with Physics-Informed Neural Networks (PINNs) and Gaussian Process Regression (GPR), QMW-Net delivers superior predictive performance and generalization across multiple test sets. The proposed model provides refined wind field support for civil aviation forecasting and trajectory planning, and shows potential for broader applications in high-dynamic flight environments and atmospheric sensing. Full article
(This article belongs to the Section Air Traffic and Transportation)
►▼ Show Figures

Figure 1

25 pages, 5610 KB  
Article
The BO-FCNN Inter-Satellite Link Prediction Method for Space Information Networks
by Xiaolan Yu, Wei Xiong and Yali Liu
Aerospace 2025, 12(9), 841; https://doi.org/10.3390/aerospace12090841 - 18 Sep 2025
Viewed by 286
Abstract
With the rapid growth in satellite types and numbers in space information networks, accurate and fast inter-satellite link prediction has become a core requirement for topology modeling and capability evaluation. However, the current space information networks are characterized by large scales and the [...] Read more.
With the rapid growth in satellite types and numbers in space information networks, accurate and fast inter-satellite link prediction has become a core requirement for topology modeling and capability evaluation. However, the current space information networks are characterized by large scales and the coexistence of multi-orbit satellites, posing dual challenges to inter-satellite link prediction. Link state prediction demands higher accuracy with limited computing power, while diverse satellite communication antenna loads require stronger generalization to adapt to different scenarios. To address these issues, this paper proposes a fully connected neural network model based on Bayesian optimization. By introducing a weighted loss function, the model effectively handles data imbalance in the link states. Combined with Bayesian optimization, the neural network hyperparameters and weighted loss function coefficients are fine-tuned, significantly improving the prediction accuracy and scene adaptability. Experimental results show that the BO-FCNN model exhibited an excellent performance on the test dataset, with an F1 score of 0.91 and an average accuracy of 93%. In addition, validation with actual satellite data from CelesTrak confirms the model’s real-world performance and its potential as a reliable solution for inter-satellite link prediction. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

24 pages, 28847 KB  
Article
Balance-URSONet: A Real-Time Efficient Pose Spacecraft Estimation Network
by Zhiyu Bi, Ming Chen, Guopeng Ding, Haodong Yan, Shihao Han, Zhaoxiong Li and Ruixue Ma
Aerospace 2025, 12(9), 840; https://doi.org/10.3390/aerospace12090840 - 17 Sep 2025
Viewed by 328
Abstract
The high-precision attitude estimation technique for non-cooperative targets in space, based on monocular cameras, has important application value in missions such as space debris removal, autonomous rendezvous and docking, and on-orbit services. However, due to the inherent missing information problem of monocular vision [...] Read more.
The high-precision attitude estimation technique for non-cooperative targets in space, based on monocular cameras, has important application value in missions such as space debris removal, autonomous rendezvous and docking, and on-orbit services. However, due to the inherent missing information problem of monocular vision systems and the high complexity of target geometry, existing monocular pose estimation methods find it difficult to realize an effective balance between accuracy and computational efficiency. Current solutions commonly adopt deep neural network architectures to improve estimation accuracy; but, this method is often accompanied by the problems of a dramatic expansion of the number of model parameters and a significant increase in computational complexity, which limits its deployment and real-time inference capabilities in real spatial tasks. To address the above problems, this paper proposes a spacecraft pose estimation network, called Balance-URSONet, which weighs the trade-off between accuracy and the number of parameters, and makes the pose estimation model have a stronger feature extraction capability by innovatively using RepVGG as the feature extraction network. In order to effectively improve the performance and inference speed of the model, this paper proposes the feature excitation unit (FEU), which is able to flexibly adjust the feature representation of the network and thus optimize the utilization efficiency of spatial and channel information. The experimental results show that the Balance-URSONet proposed in this paper has excellent performance in the spacecraft pose estimation task, with an ESA score of 0.13 and a parameter count 13 times lower than that of URSONet. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

17 pages, 1933 KB  
Article
Air Traffic Complexity Analysis in Multi-Airport Terminal Areas Based on Route Segment–Flight State Interdependent Network
by Chuanlong Zhang, Xiangxi Wen, Minggong Wu, Libiao Zhang, Hanchen Xie, Lingzhong Meng and Jiale Yang
Aerospace 2025, 12(9), 839; https://doi.org/10.3390/aerospace12090839 - 17 Sep 2025
Viewed by 195
Abstract
An analysis of air traffic complexity in multi-airport terminal areas can assist air traffic controllers in accurately assessing the air traffic situation and collaboratively managing air traffic flows, thereby enhancing the utilization of airspace resources and reducing flight delays. This paper proposes an [...] Read more.
An analysis of air traffic complexity in multi-airport terminal areas can assist air traffic controllers in accurately assessing the air traffic situation and collaboratively managing air traffic flows, thereby enhancing the utilization of airspace resources and reducing flight delays. This paper proposes an air traffic complexity analysis method for multi-airport terminal areas based on a route segment–flight state interdependent network. The interdependent network model consists of an upper-layer flight state network, a lower-layer route segment network, and inter-layer coupling edges. The upper-layer network is constructed with aircraft as nodes and flight conflicts between aircraft as edges. The lower-layer network uses route segments as nodes and the connectivity between route segments as edges. The inter-layer coupling edges are determined by evaluating the relationship between aircraft and route segments—if an aircraft is on a specific route segment, a coupling edge exists between the corresponding aircraft node and route segment node. Based on this model, node-level complexity metrics are established to analyze the importance and complexity of individual route segments. Additionally, network-level complexity metrics are introduced to assess the overall air traffic complexity in multi-airport terminal areas. Finally, the method proposed in this paper is validated using flight scenarios in the Guangdong–Hong Kong–Macao Greater Bay Area. By comparing and analyzing the results with the actual situation, it is shown that the proposed method can accurately assess the air traffic complexity in multi-airport terminal areas. Full article
(This article belongs to the Section Air Traffic and Transportation)
►▼ Show Figures

Figure 1

23 pages, 1036 KB  
Article
Reusability Flight Experiment Guidance: Trajectory Correction After Ascent
by Jose Luis Redondo Gutierrez, David Seelbinder and Stephan Theil
Aerospace 2025, 12(9), 838; https://doi.org/10.3390/aerospace12090838 - 17 Sep 2025
Viewed by 181
Abstract
This paper presents the design and implementation of a guidance algorithm for the re-entry vehicle ReFEx (Reusability Flight Experiment). This algorithm aims at correcting for the dispersion in position and velocity after separation from the launcher, by updating the trajectory. The need for [...] Read more.
This paper presents the design and implementation of a guidance algorithm for the re-entry vehicle ReFEx (Reusability Flight Experiment). This algorithm aims at correcting for the dispersion in position and velocity after separation from the launcher, by updating the trajectory. The need for this update is driven by the expected divergence from the nominal trajectory at separation, due to the use of an unguided launcher. The transcription of the problem into an optimal control problem is used as a baseline for verification purposes. This algorithm consists of a simplification of the optimal control problem, reducing the profiles of the control variables to a finite set of control parameters. Combining this problem reduction with a function that propagates the trajectory from the initial state, this approach is able to transform the problem into an unconstrained optimization problem. This paper shows that this simplification is able to find solutions of similar quality to the full optimal control approach. The resulting algorithm is proven real-time capable by deploying it into a hardware equivalent of the on-board computer. In addition, a strategy to diverge during flight to an alternative target if the nominal one cannot be reached is appended to the algorithm. Full article
(This article belongs to the Special Issue Flight Guidance and Control)
►▼ Show Figures

Figure 1

15 pages, 891 KB  
Article
Reinforced Model Predictive Guidance and Control for Spacecraft Proximity Operations
by Lorenzo Capra, Andrea Brandonisio and Michèle Roberta Lavagna
Aerospace 2025, 12(9), 837; https://doi.org/10.3390/aerospace12090837 - 17 Sep 2025
Viewed by 324
Abstract
An increased level of autonomy is attractive above all in the framework of proximity operations, and researchers are focusing more and more on artificial intelligence techniques to improve spacecraft’s capabilities in these scenarios. This work presents an autonomous AI-based guidance algorithm to plan [...] Read more.
An increased level of autonomy is attractive above all in the framework of proximity operations, and researchers are focusing more and more on artificial intelligence techniques to improve spacecraft’s capabilities in these scenarios. This work presents an autonomous AI-based guidance algorithm to plan the path of a chaser spacecraft for the map reconstruction of an artificial uncooperative target, coupled with Model Predictive Control for the tracking of the generated trajectory. Deep reinforcement learning is particularly interesting for enabling spacecraft’s autonomous guidance, since this problem can be formulated as a Partially Observable Markov Decision Process and because it leverages domain randomization well to cope with model uncertainty, thanks to the neural networks’ generalizing capabilities. The main drawback of this method is that it is difficult to verify its optimality mathematically and the constraints can be added only as part of the reward function, so it is not guaranteed that the solution satisfies them. To this end a convex Model Predictive Control formulation is employed to track the DRL-based trajectory, while simultaneously enforcing compliance with the constraints. Two neural network architectures are proposed and compared: a recurrent one and the more recent transformer. The trained reinforcement learning agent is then tested in an end-to-end AI-based pipeline with image generation in the loop, and the results are presented. The computational effort of the entire guidance and control strategy is also verified on a Raspberry Pi board. This work represents a viable solution to apply artificial intelligence methods for spacecraft’s autonomous motion, still retaining a higher level of explainability and safety than that given by more classical guidance and control approaches. Full article
(This article belongs to the Special Issue Advanced AI and Robotic Technologies for Spacecraft Modelling, Optimization, and Decision-Making)
►▼ Show Figures

Figure 1

22 pages, 3010 KB  
Article
A Study of Mechanical Behavior of Folding and Welding Connections of Kapton Films While Manufacturing a Solar Sail
by Yu Hu, Hao Liu, Enze Qiao and Wujun Chen
Aerospace 2025, 12(9), 836; https://doi.org/10.3390/aerospace12090836 - 17 Sep 2025
Viewed by 217
Abstract
Large-area membrane spacecraft, such as solar sails, must be tightly stowed before launch. However, excessive folding readily induces plastic creases that impede full on-orbit deployment and degrade membrane surface accuracy. To overcome this challenge, this study aims to quantify the mechanical response of [...] Read more.
Large-area membrane spacecraft, such as solar sails, must be tightly stowed before launch. However, excessive folding readily induces plastic creases that impede full on-orbit deployment and degrade membrane surface accuracy. To overcome this challenge, this study aims to quantify the mechanical response of Kapton films during folding and to establish a reliable welding process for post-fold sail membranes. Based on the theory of linear elastic engineering, an S-shaped folding model was theoretically simplified to obtain the relationship between the rebound force P of adjacent contact thin films and the thin-film spacing h. Then, the Kapton film folding process was numerically simulated based on the implicit static method by using ABAQUS. The stress–strain curves and mechanical parameters of the thin films measured through uniaxial tensile tests are applied to theoretical and numerical results. It is found that the P-h curves obtained by the theoretical, numerical, and experimental method have good consistency. Step-loaded creep tests show that, after 6 h, the mean spacing reductions Δh are 0.43 mm for 50 µm thin films and 1.05 mm for 125 µm thin films, matching simulation results within 3%. Finally, uniaxial tensile tests are conducted on the welded thin films to measure the strength of the thin-film welds under different welding temperatures and pressures. The tensile force and elongation required to eliminate weld wrinkles are also measured to explore the welding connection of Kapton film. Further, for 50 µm thin films with a 10 mm weld width, eliminating welding-induced wrinkles requires a tensile force of 9.61 N and an elongation of 0.43%. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

26 pages, 4941 KB  
Article
Experimental Investigation of Hydrogen Peroxide and Nitrous Oxide in a 1-Newton Catalyst-Based Monopropellant Research Thruster
by Florian Merz, Till Hörger, Johan Steelant, Felix Lauck and Christoph Kirchberger
Aerospace 2025, 12(9), 835; https://doi.org/10.3390/aerospace12090835 - 17 Sep 2025
Viewed by 258
Abstract
As part of the GreenRAIM activity of the European Space Agency (ESA), an extensive test campaign involving various monopropellants was undertaken. In this work, design and test results of an additively manufactured 1-Newton monopropellant thruster are shown. The detailed design of the thruster [...] Read more.
As part of the GreenRAIM activity of the European Space Agency (ESA), an extensive test campaign involving various monopropellants was undertaken. In this work, design and test results of an additively manufactured 1-Newton monopropellant thruster are shown. The detailed design of the thruster and the experimental setup are presented. The first part of the test campaign was conducted with 98 wt.% hydrogen peroxide as the propellant and a commercially available Pt/Al2O3 catalyst. The second part was carried out with the same thruster but using nitrous oxide as the propellant and an iridium-based catalyst. The test data acquired was used to validate a comprehensive, generic model for monopropellant thrusters within the simulation software EcosimPro/ESPSS v3.7, which was developed within the activity. Full article
(This article belongs to the Special Issue Green Propulsion: Present Solutions and Perspectives for Powering Environmentally Friendly Space Missions (2nd Edition))
►▼ Show Figures

Figure 1

17 pages, 3186 KB  
Article
Geostationary Orbit Target Detection Based on Min-Stacking Method
by Kaiyuan Zheng, Can Xu, Yasheng Zhang, Jiayu Qiu and Xia Wang
Aerospace 2025, 12(9), 834; https://doi.org/10.3390/aerospace12090834 - 17 Sep 2025
Viewed by 203
Abstract
The geostationary orbit (GEO), about 35,786 km above the Earth’s equator, hosts high-value satellites like communication, meteorological, and navigation ones. Real-time detection of geostationary orbit targets is crucial for orbital resource safety and satellite operation. Large field-of-view (FOV) telescopes can observe many such [...] Read more.
The geostationary orbit (GEO), about 35,786 km above the Earth’s equator, hosts high-value satellites like communication, meteorological, and navigation ones. Real-time detection of geostationary orbit targets is crucial for orbital resource safety and satellite operation. Large field-of-view (FOV) telescopes can observe many such targets but face technical bottlenecks due to their optical systems, such as weak light-gathering capability, stellar interference, and complex stray light. This paper analyzes the apparent motion differences between stars and geostationary orbit targets based on the telescope’s staring mode. Stars move overall in images while GEO targets are relatively stationary. A minimum value stacking (Min-Stacking) method is proposed to suppress stars, improving GEO targets’ signal-to-noise ratio. With the global threshold segmentation algorithm, fast and accurate target extraction is achieved. Experiments show the method has high detection rates, overcomes interference, and features simplicity and real-time performance, with important application value. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

44 pages, 4855 KB  
Perspective
The Technical Hypothesis of a Missile Engine Conversion and Upgrade for More Sustainable Orbital Deployments
by Emilia-Georgiana Prisăcariu, Oana Dumitrescu, Francesco Battista, Angelo Maligno, Juri Munk, Daniele Ricci, Jan Haubrich and Daniele Cardillo
Aerospace 2025, 12(9), 833; https://doi.org/10.3390/aerospace12090833 - 16 Sep 2025
Viewed by 251
Abstract
The conversion of legacy missile engines into space propulsion systems represents a strategic opportunity to accelerate Europe’s access to orbit while advancing sustainability and circular-economy goals. Rather than discarding decommissioned hardware, repurposing missile propulsion can reduce development timelines, retain valuable materials, and leverage [...] Read more.
The conversion of legacy missile engines into space propulsion systems represents a strategic opportunity to accelerate Europe’s access to orbit while advancing sustainability and circular-economy goals. Rather than discarding decommissioned hardware, repurposing missile propulsion can reduce development timelines, retain valuable materials, and leverage proven architectures for new applications. This perspective outlines the potential of the Soviet-era Isayev S2.720 engine as a representative case, drawing on historical precedents of missile-to-launcher conversions worldwide. A three-pillar methodology is proposed to frame such efforts: (i) the adoption of cleaner propellants such as LOX–LCH4 in place of toxic hypergolics; (ii) remanufacturing and upgrading of key subsystems through additive manufacturing, AI-assisted inspection, and digital twin modelling; and (iii) validation supported by dedicated testing, life-cycle assessment (LCA), and life-cycle costing (LCC). Beyond the technical aspects, the paper discusses retrofit applicability, cost considerations, and the role of standardization in enabling future certification. By positioning the S2.720 as a model, this study highlights the broader strategic value of adapting decommissioned propulsion systems for modern orbital use, providing insight into how Europe might integrate legacy assets into a more sustainable and resilient space transportation framework. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

16 pages, 8135 KB  
Article
Failure Analysis of Composite Curved Beam with Initial Delamination Damage
by Xiaojing Zhang, Kai Shao and Xinyu Niu
Aerospace 2025, 12(9), 832; https://doi.org/10.3390/aerospace12090832 - 16 Sep 2025
Viewed by 222
Abstract
This paper provides a comprehensive analysis of common manufacturing delamination defects in composite curved beams, as well as delamination issues arising from cutting processes in engineering practice. Curved beams, widely used as connecting components in the aviation industry, are susceptible to delamination under [...] Read more.
This paper provides a comprehensive analysis of common manufacturing delamination defects in composite curved beams, as well as delamination issues arising from cutting processes in engineering practice. Curved beams, widely used as connecting components in the aviation industry, are susceptible to delamination under out-of-plane loads. This study employs three-dimensional finite element methods and progressive damage failure analysis to examine the impact of delamination damage on the load-bearing capacity of curved beam structures under four-point bending loads. The investigation focuses on three key factors: delamination size, the position of delamination along the thickness direction, and the in-plane position of delamination. The results indicate that for the orthotropic symmetric layup used in this study, the closer the initial delamination is to the midplane of the curved beam, the more significant the reduction in load-bearing capacity. Delamination in the lower part of the beam has a greater impact than in the upper part, and edge delamination poses a greater threat to the structure compared to center-width delamination. These findings can offer valuable technical support for engineering tolerance management. Full article
►▼ Show Figures

Figure 1

26 pages, 6175 KB  
Article
Geometrically Nonlinear Analysis of Composite Beams Based Using a Space–Time Finite Element Method
by Xin Hu, Lidao Chen and Yong Liu
Aerospace 2025, 12(9), 831; https://doi.org/10.3390/aerospace12090831 - 16 Sep 2025
Viewed by 186
Abstract
In this paper, we present a transient-format time-continuous Galerkin finite element method for fully intrinsic geometrically exact beam equations that are energy-consistent. Within the grid of space and time, we derive governing equations for elements using the Galerkin method and the time finite [...] Read more.
In this paper, we present a transient-format time-continuous Galerkin finite element method for fully intrinsic geometrically exact beam equations that are energy-consistent. Within the grid of space and time, we derive governing equations for elements using the Galerkin method and the time finite element method, implement variable interpolation via Legendre functions, and establish an assembly process for space–time finite element equations. The key achievement is the realization of the free order variation of the program, which provides a basis for future research on adaptive algorithms. In particular, the variable order method reduces the quality requirements for the mesh. In regions with a higher degree of nonlinearity, it is easier to increase the variable order, and the result is smoother. Meanwhile, increasing the interpolation order effectively enhances computational accuracy. Introducing kinematical equations of rotation with Lagrange operators completely imposes the conservative loads on fully intrinsic equations. This means that loads in the inertial coordinate system, such as gravity, can also be iterated synchronously in the deformed coordinate system. Through a set of illustrative examples, our algorithm demonstrates effectiveness in addressing conservative loads, elastic coupling deformation, and dynamic response, demonstrating the ability to analyze elastically coupled dynamic problems pertaining to helicopter rotors. Full article
(This article belongs to the Section Aeronautics)
►▼ Show Figures

Figure 1

21 pages, 7752 KB  
Article
Evaluation of Stress Corrosion Cracking Susceptibility of 2195-T8 Al-Li Alloy in Propellant Environment Using Slow Strain Rate Testing
by Yilin Zhao, Gan Tian, Dejun Liu, Biyun Ren, Wei Zhang and Yafeng Zhu
Aerospace 2025, 12(9), 830; https://doi.org/10.3390/aerospace12090830 - 16 Sep 2025
Viewed by 157
Abstract
The stress corrosion cracking (SCC) susceptibility of 2195-T8 Al-Li alloy in N2O4 medium was evaluated using slow strain rate testing (SSRT). The electrochemical corrosion behavior and morphological evolution of the alloy under different conditions were further examined through potentiodynamic polarization [...] Read more.
The stress corrosion cracking (SCC) susceptibility of 2195-T8 Al-Li alloy in N2O4 medium was evaluated using slow strain rate testing (SSRT). The electrochemical corrosion behavior and morphological evolution of the alloy under different conditions were further examined through potentiodynamic polarization measurements. The results indicate that with the increase in electrochemical corrosion rate, the corrosion morphology of the alloy extends from localized pitting and intergranular corrosion to severe exfoliation corrosion. In the N2O4 medium, the alloy exhibits significant susceptibility to SCC at tensile rates of ε ≥ 5 × 10−6 s−1. However, when strained at ε = 10−6 s−1, a sudden increase in ISCC is observed accompanied by a transition to brittle intergranular fracture mediated by anodic dissolution. At the same stretch rate (ε = 10−6 s−1), the susceptibility to SCC of the alloy in N2O4 medium increased with higher water content ω(H2O). This trend is attributed to enhanced generation of HNO3 and HNO2, as well as increased diffusion of hydrogen—produced by the cathodic reaction—to the crack tip. The synergistic interaction between anodic dissolution and hydrogen embrittlement ultimately promotes the initiation and propagation of SCC in the alloy. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

26 pages, 2889 KB  
Article
Advanced Implementation of the Asymmetric Distribution Expectation-Maximum Algorithm in Fault-Tolerant Control for Turbofan Acceleration
by Xinhai Zhang, Jia Geng, Kang Wang, Ming Li and Zhiping Song
Aerospace 2025, 12(9), 829; https://doi.org/10.3390/aerospace12090829 - 16 Sep 2025
Viewed by 290
Abstract
For the safety and performance of turbofan engines, the fault-tolerant control of acceleration schedules is becoming increasingly necessary. However, traditional probabilistic approaches struggle to satisfy the single-side surge boundary limits and control asymmetry. Moreover, the baseline fault-tolerance requirement of the acceleration schedule cannot [...] Read more.
For the safety and performance of turbofan engines, the fault-tolerant control of acceleration schedules is becoming increasingly necessary. However, traditional probabilistic approaches struggle to satisfy the single-side surge boundary limits and control asymmetry. Moreover, the baseline fault-tolerance requirement of the acceleration schedule cannot depend on whether fault detection exists, and model-dependent data approaches inherently limit their generalizability. To address all these challenges, this paper proposes a probabilistic viewpoint of non-frequency and non-Bayesian schools, and the asymmetric distribution expectation-maximum algorithm (ADEMA) based on this viewpoint, along with their detailed theoretical derivations. The surge boundary enhances safety requirements for the acceleration control; therefore, simulations and verifications consider the disturbance combinations involving a single significant fault alongside normal deviations from other factors, including minor faults. In the event of such disturbances, ADEMA can effectively prevent the acceleration process from approaching the surge boundary, both at sea level and within the flight envelope. It demonstrates the smallest median estimation error (0.27% at sea level and 0.96% within the flight envelope) compared to other methods, such as the Bayesian weighted average method. Although its maintenance of performance is not exceptionally strong, its independence from model-data makes it a valuable reference. Full article
(This article belongs to the Section Aeronautics)
►▼ Show Figures

Figure 1

29 pages, 2881 KB  
Article
Distributed Cooperative Control of Flexible Spacecraft Based on PDE-ODE Coupled Dynamics Model
by Kai Cao, Pan Sun, Zhitao Zhou, Fan Mo, Liguo Wang, Haiyang Li, Kaiheng Xiang and Shuang Li
Aerospace 2025, 12(9), 828; https://doi.org/10.3390/aerospace12090828 - 15 Sep 2025
Viewed by 220
Abstract
With the increasing application of smart-material-based actuators for vibration suppression in flexible spacecraft, there is a growing need for advanced control strategies suited to distributed-parameter systems. This paper proposes a distributed cooperative control (DCC) scheme to address phase inconsistencies in actuator outputs within [...] Read more.
With the increasing application of smart-material-based actuators for vibration suppression in flexible spacecraft, there is a growing need for advanced control strategies suited to distributed-parameter systems. This paper proposes a distributed cooperative control (DCC) scheme to address phase inconsistencies in actuator outputs within a decentralized control framework. The piezoelectric actuators embedded in flexible appendages are modeled as a multi-agent system that utilizes local information to improve coordination. A consensus-based cooperative controller is designed to synchronize actuator actions, with closed-loop stability rigorously established via Lyapunov’s direct method. The robustness of the controller is evaluated through Monte Carlo simulations under varying initial conditions. Comparative numerical results demonstrate that the proposed DCC achieves superior performance and energy efficiency over conventional decentralized control, along with inherent fault tolerance due to its distributed topology. Furthermore, the practical implementability of the approach is supported by discrete-time controller validation and automatic code generation, confirming its readiness for real-time embedded deployment. The study highlights the potential of DCC for enhancing vibration suppression in next-generation flexible spacecraft. Full article
(This article belongs to the Section Astronautics & Space Science)
►▼ Show Figures

Figure 1

25 pages, 1684 KB  
Review
Advanced Fiber Optic Sensing Technology in Aerospace: Packaging, Bonding, and Calibration Review
by Zhen Ma, Xiyuan Chen, Bingbo Cui and Xinzhong Wang
Aerospace 2025, 12(9), 827; https://doi.org/10.3390/aerospace12090827 - 15 Sep 2025
Viewed by 528
Abstract
With the continuous development of science and technology, aircraft structural health monitoring (SHM) has become increasingly important in the aviation field. As a key component of SHM, wing deformation monitoring is of great significance for ensuring flight safety and reducing maintenance costs. The [...] Read more.
With the continuous development of science and technology, aircraft structural health monitoring (SHM) has become increasingly important in the aviation field. As a key component of SHM, wing deformation monitoring is of great significance for ensuring flight safety and reducing maintenance costs. The traditional strain gauge measurement method can no longer meet the needs of modern aeronautical engineering. Fiber Bragg grating (FBG) sensors have been widely used in the engineering field due to their unique advantages, and have shown great potential in aircraft wing deformation monitoring. In the context of SHM in the aircraft field, this article provides an overview of four aspects: classification and principles of fiber optic sensors, packaging forms of FBG sensors, bonding technology, and calibration technology. The packaging forms includes tube-packaged, embedded package and surface-attached package. It then discuss the bonding technology of FBG sensors, and the principle and influencing factors of fiber optic bonding technology are analyzed. Finally, it conducts in-depth research on the calibration technology of FBG sensors. Through comprehensive analysis of these four aspects, the suggestions for optical fiber sensing technology in aircraft wing deformation measurement are summarized and put forward. Full article
(This article belongs to the Section Aeronautics)
►▼ Show Figures

Figure 1

17 pages, 4787 KB  
Article
The Development of a Prototype for Low Altitude Operations of Unmanned Aircraft Flight Plan Systems
by Siriporn Yenpiem, Soemsak Yooyen, Anucha Tungkasthan, Sasicha Banchongaksorn and Keito R. Yoneyama
Aerospace 2025, 12(9), 826; https://doi.org/10.3390/aerospace12090826 - 15 Sep 2025
Viewed by 316
Abstract
The use of Unmanned Aircraft has grown significantly in Thailand and worldwide, particularly for operations below 450 feet. However, unlike manned aviation, there remains a lack of integrated digital platforms to manage flight plans that align with regulatory and operational requirements specific to [...] Read more.
The use of Unmanned Aircraft has grown significantly in Thailand and worldwide, particularly for operations below 450 feet. However, unlike manned aviation, there remains a lack of integrated digital platforms to manage flight plans that align with regulatory and operational requirements specific to low altitude activity. This study employed both secondary research and expert interviews to gather technical and regulatory user requirements. The data were analyzed and validated using Structural Equation Modeling to identify key variables influencing safety operations. Based on these findings, a standardized low altitude flight plan format was developed and converted into a prototype web platform called GoFly. The system enables operators to register aircraft and pilot credentials and to submit flight plans digitally. This platform addresses the current fragmentation in Thailand’s flight planning process by centralizing operations and enhancing regulatory compliance. The study contributes to the foundational development of a digital Unmanned Aircraft Traffic Management system tailored for emerging airspace users in Thailand and demonstrates potential scalability to other international regulatory contexts. Full article
(This article belongs to the Special Issue Flight Guidance and Control)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-106
Previous Issue
Next Issue
Back to TopTop