Astrodynamics最新文献

{"title":"Self-organized control of spacecraft formation flying on irregular curves for cooperative observation","authors":"Hao Zhou,&nbsp;Zhaohui Dang,&nbsp;Jianping Yuan","doi":"10.1007/s42064-025-0284-2","DOIUrl":"10.1007/s42064-025-0284-2","url":null,"abstract":"<div><p>This paper comprehensively studies the self-organized deployment of a spacecraft cluster on a smooth irregular closed curve for cooperative on-orbit observation of a target spacecraft. The expected configuration curve is constructed by a set of control points through cubic B-spline interpolation, and it is closed and C2 continuous on the entire curve including its endpoints. As a necessary step for designing the control law, an efficient iterative algorithm for calculating the maneuvering spacecraft’s nearest point on the curve is developed using Newton downhill method. Then the double-layer feedback controllers are designed, in which the inner controller makes the temporary target positions approximately uniformly converge to the curve, and the outer controller guides the actual positions to the temporary target positions. In this way, the spacecraft cluster can be accurately deployed on the desired curvilinear formation. The stability of the closed-loop system with the double-layer controller is also proved. Finally, a boat-shaped target configuration curve for comprehensively cooperatively observing a spherical target spacecraft is simulated and analyzed. The detailed results demonstrate that the designed self-organized control law can successfully achieve the desired formation flying with low control magnitude, acceptable accuracy, and reduce the influence of single spacecraft’s failure to the final configuration’s uniformity and the observation tasks.</p><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 2","pages":"339 - 363"},"PeriodicalIF":6.5,"publicationDate":"2026-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147751216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Earth–Moon transfer via the L1 Lagrangian point using the theory of functional connections","authors":"Allan Kardec de Almeida Jr.,&nbsp;Vitor Martins de Oliveira,&nbsp;Timothée Vaillant,&nbsp;Dalmiro Jorge Filipe Maia,&nbsp;Alexandre C. M. Correia,&nbsp;Domingos Barbosa,&nbsp;Leonardo Barbosa Torres dos Santos","doi":"10.1007/s42064-025-0297-x","DOIUrl":"10.1007/s42064-025-0297-x","url":null,"abstract":"<div><p>Future exploration of the Moon will involve numerous both crewed and uncrewed launches, essential for transporting materials and instruments critical to the success of lunar missions. The <i>L</i>₁ Lagrangian point can represent an ideal transit hub for space missions due to its dynamical properties and strategic location between Earth and Moon. This paper shows an efficient and systematic technique based on the theory of functional connections to evaluate transfers from Earth to Moon, making use of the stable/unstable manifolds associated with the family of Lyapunov orbits around <i>L</i>₁. Tens of millions of transfers are evaluated, narrowing the space of solutions to the ones with the lowest costs in an extensive investigation. The transfer is designed under the circular restricted three-body problem formulation with a specific system of coordinates and constraints. A Moon flyby is followed by an entry into a Lyapunov orbit around <i>L</i>₁, from where a final transfer to the Moon is performed, with every leg aided by an invariant manifold. The results show a reduced fuel consumption of at least 58.80 m/s as compared to the literature. This difference can be useful for mission designers, while the efficiency of the technique can potentially extend the results to other types of transfers in space.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 4","pages":"607 - 623"},"PeriodicalIF":8.1,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s42064-025-0297-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148719127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic modeling and active vibration control of an on-orbit assembled planar phased array antenna with numerous revolute clearance hinges","authors":"Chaochen Jin,&nbsp;Xiang Liu,&nbsp;Guoping Cai,&nbsp;Fucheng Liu,&nbsp;Jun Sun,&nbsp;Dongfang Zhu","doi":"10.1007/s42064-025-0286-0","DOIUrl":"10.1007/s42064-025-0286-0","url":null,"abstract":"<div><p>The shape accuracy of a space phased array antenna is crucial in determining its performance. In the antenna structure, the clearances, geometric deviations, and flexibilities of numerous revolute hinges significantly affect the analysis and control of antenna shape accuracy. This paper proposes the comprehensive dynamic modeling method and active vibration control method of the antenna structure with numerous hinges. First, by introducing the nonlinear contact force of hinges into the finite element method, the nonlinear dynamic model of the antenna structure with hinge clearances and flexibilities is established. Based on the polynomial fitting method, a model order reduction method is employed to simplify the nonlinear dynamic model. Then, to address the geometric deviation problem of numerous hinges, a model updating method based on clustering optimization and frequency criterion is proposed. Finally, an active vibration control method using cable actuators is proposed to reduce the nonlinear vibration of the antenna structure with numerous hinges, and an actuator distribution optimization method is established. The numerical simulation results demonstrate that the proposed nonlinear dynamic model can well reflect the influence of the hinges on the antenna structure and that the proposed control method can effectively suppress the nonlinear vibration.</p><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 2","pages":"365 - 382"},"PeriodicalIF":6.5,"publicationDate":"2026-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147751220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Augmented temporal grid for graph neural networks and anomaly detection in spacecraft","authors":"Gamze Naz Kiprit,&nbsp;Andreas Koch,&nbsp;Michael Petry,&nbsp;Martin Werner","doi":"10.1007/s42064-025-0278-0","DOIUrl":"10.1007/s42064-025-0278-0","url":null,"abstract":"<div><p>Graph neural networks (GNN) for spatiotemporal problems incorporate a temporal module operating on a temporal grid of interconnected subsequent time steps. In this work, we explore adding connections to future time steps to the temporal grid in order to extract unique features for the task of anomaly detection in time series. We introduce strategies for determining future connections utilizing the autocorrelation function and different random sampling techniques. The effectiveness of resulting graph neural networks is demonstrated on multiple anomaly detection benchmarks, including spacecraft telemetry datasets. A selection of graph neural network models is further deployed on the AMD-Xilinx Versal AI Core SoC to measure the execution time and resource utilization when processing telemetry data.</p><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 on","pages":"403 - 416"},"PeriodicalIF":6.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s42064-025-0278-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148008710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Field-of-view constrained three-dimensional impact time and angle guidance via dual-step joint approach","authors":"Peng Zhang,&nbsp;Nan Zhang,&nbsp;Zheng Dai,&nbsp;Yu Chen,&nbsp;Shengping Gong","doi":"10.1007/s42064-025-0280-6","DOIUrl":"10.1007/s42064-025-0280-6","url":null,"abstract":"<div><p>A field-of-view constrained three-dimensional impact time and angle guidance law is proposed in this paper. The challenging guidance problem formulated in the three-dimensional scenario while considering multiple constraints is addressed via the proposed dual-step joint approach. The guidance process consists of two steps. In the first step, the equiangular spiral shaping trajectory is conducted to achieve the desired impact time while adhering to the field-of-view constraint. In the second step, the field-of-view constrained impact angle guidance law is derived by employing the error dynamics and auxiliary function. The switching point between the guidance laws in the two steps needs to be determined quickly and accurately. The guidance parameters can be obtained efficiently by employing the three-point secant method, solving a nonlinear implicit equality with 2–3 iterations. Numerical simulation examples are provided to verify the performance of the proposed guidance law on different guidance constraints.</p><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 2","pages":"299 - 317"},"PeriodicalIF":6.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147751215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of deployment and operational strategies for Starlink Stage I LEO constellation based on TLE","authors":"Yingying Qu,&nbsp;Jingshi Tang","doi":"10.1007/s42064-025-0293-1","DOIUrl":"10.1007/s42064-025-0293-1","url":null,"abstract":"<div><p>As satellite application tasks become increasingly complex, low Earth orbit (LEO) satellite constellations, with advantages such as low launch costs and excellent coverage performance, are gradually becoming the preferred solution for many missions. Many LEO constellation projects have been progressively deployed, with the Starlink satellite constellation being the largest in terms of the number of satellites launched. It was proposed and built by SpaceX, and the details of its deployment and operation strategy have not been fully disclosed. Many studies have analyzed Starlink’s strategy based on actual satellite orbital data, but these have focused mainly on earlier, smaller datasets, and have not discussed the deployment process of more recent launch batches or the use of low thrusters. This article attempts to analyze the recent deployment and operational strategy of Starlink’s first-stage LEO constellation based on the publicly available TLE (two-line element) data. First, the actual configuration of the Starlink constellation is examined. Then, the deployment strategy and the thrust are analyzed based on the changes in the orbital elements. Afterward, the backup and replacement strategy is analyzed by examining the satellite scheduling during their operational stage in their working orbital positions. Finally, the post-mission disposal and deorbit maneuver, if any, are discussed.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 4","pages":"575 - 587"},"PeriodicalIF":8.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148719090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of trajectory design and optimization methods for ice giant exploration","authors":"Guoliang Liang,&nbsp;Yu Zhang,&nbsp;Hongwei Yang,&nbsp;Hexi Baoyin","doi":"10.1007/s42064-026-0308-6","DOIUrl":"10.1007/s42064-026-0308-6","url":null,"abstract":"<div><p>The exploration of ice giant systems represents one of the priority areas in deep space exploration for the coming decade. Owing to the vast orbital distances of these planets and the need for extensive in-system transfers during missions, trajectory design and optimization constitute a critical enabling technology for the exploration of ice giant systems. While numerous mission concepts and orbital design methodologies have been proposed to date, a comprehensive review of these methodologies is currently lacking, which hinders the further development of novel design techniques and the formulation of new mission proposals. This survey systematically synthesizes both established and state-of-the-art methods across four primary mission phases: interplanetary transfer, ice giant capture, planetary satellite tours, and other scientific observations targeting planets and comets. For each phase, different design strategies are introduced, with their advantages and capabilities described and analyzed to reveal technological progress. Finally, perspectives on future developments are provided, aiming to establish a reference framework for further research in trajectory design and optimization for ice giant system exploration.\u0000</p><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 2","pages":"199 - 218"},"PeriodicalIF":6.5,"publicationDate":"2026-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147751217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Orbit reconstruction for HERMES-SP/TP satellite mission","authors":"Mile Karlica,&nbsp;Pavel Jefremov,&nbsp;Andrea Colagrossi,&nbsp;Michèle R. Lavagna,&nbsp;Andreja Gomboc","doi":"10.1007/s42064-025-0289-x","DOIUrl":"10.1007/s42064-025-0289-x","url":null,"abstract":"<div><p>We present techniques for the reconstruction of satellite’s low Earth equatorial orbit during a GPS coverage gap for HERMES Pathfinder mission. The HERMES Scientific+Technological Pathfinder mission is conceived to consist of six satellites in a circular, equatorial, low Earth orbit at a height of 500–550 km. Each satellite will be equipped with a single GPS antenna. Therefore, GPS coverage gaps, where the satellite cannot establish contact with at least four GPS satellites, can last up to 25 min. We developed two methods for orbit determination within the coverage gap using known satellite positions before and after the gap: (1) polynomial and Fourier interpolation and (2) first- and second-order corrections to the Keplerian orbit. We tested both methods on simulated data and found them suitable, giving the accuracy required for the location of a satellite ⩽30 m in &gt; 99% of simulated gaps. The robustness of the methods was examined against simulated orbits with different values of inclinations and eccentricities. The first method gives consistent performance against eccentricity for coverage gaps lasting up to 20 min, while it shows a noticeable drop in performance at eccentricities above 0.01 for 25 min long gaps. The performance of the second method does not change with eccentricity within the investigated range, it also does not strongly depend on inclination and remains &gt; 98%. With varying inclination, in the first method, the decrease in performance becomes evident for gaps longer than 20 min. The first method gives satellite position in the form of analytical function and can be used as a continuous satellite position determination procedure between two GPS telemetry updates, while the second method is limited by discrete output at expected GPS telemetry updates. Concerning the influence of solar activity on nanosatellite motion, all methods show similar levels of robustness and stability.</p><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 2","pages":"383 - 400"},"PeriodicalIF":6.5,"publicationDate":"2026-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147751142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AI-assisted hazard detection for safe lunar landing","authors":"Luca Ostrogovich,&nbsp;Alfredo Renga,&nbsp;Roberto Del Prete,&nbsp;Simone Giannattasio,&nbsp;Luca Andolfi,&nbsp;Giuseppe Tomasicchio","doi":"10.1007/s42064-025-0288-y","DOIUrl":"10.1007/s42064-025-0288-y","url":null,"abstract":"<div><p>Identifying hazards that could compromise a safe landing is a critical step of the final phases of a lander’s descent trajectory. Landing on a harsh terrain can lead to the lander tipping over or prevent a deployed payload from fulfilling its mission. Many attempts to develop hazard detection systems failed to provide a comprehensive and robust assessment of the hazards present in the landing area, particularly under adverse lighting conditions. The proposed algorithm utilizes deep learning techniques combined with standard processing methods to deliver a secure landing site to the onboard guidance, navigation, and control (GNC) system. By integrating data from optical images and LiDAR point clouds, the algorithm evaluates slope, extent, local roughness, presence of obstacles, transient shadows, and permanently shadowed regions, while also considering the fuel expenses required to reach the designated site. The deep learning algorithm’s training and validation, as well as the hazard detection pipeline’s testing, were conducted using synthetic images and point clouds generated from a virtual simulation environment created in Unreal Engine, which enabled varying lighting conditions and lander orientation and altitude. The terrain was generated by enhancing the resolution of the lunar reconnaissance orbiter (LRO) digital elevation model (DEM), with the possibility to introduce synthetic obstacles such as rocks and craters, allowing for a realistic and comprehensive assessment of the algorithm’s performance in different lunar surface scenarios. The algorithm has yielded satisfactory outcomes, effectively pinpointing a secure landing location across all conducted tests, thus reaffirming the validity of the approach.</p><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 on","pages":"449 - 464"},"PeriodicalIF":6.5,"publicationDate":"2026-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148009966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization and deployment method of cislunar communication and navigation constellation based on libration point orbits","authors":"Zheyu Xu,&nbsp;Zicong An,&nbsp;Defeng Gu,&nbsp;Lan Du,&nbsp;Xiao Chen,&nbsp;Lisheng Tong","doi":"10.1007/s42064-025-0279-z","DOIUrl":"10.1007/s42064-025-0279-z","url":null,"abstract":"<div><p>The Earth–Moon libration point orbit (LPO) offers unique advantages in terms of location and dynamical characteristics, providing new opportunities for designing communication and navigation constellations. However, LPOs cannot be described by Keplerian elements and require significant computational resources for initial value searches, limiting their optimization potential. This paper proposes a two-step optimization algorithm based on a two-layer initial value library. The first layer represents orbit families, while the second layer contains orbits with varying amplitudes within each family. The first step of the algorithm quickly filters orbit families, and the second step selects the orbits that form the constellation, significantly reducing both the optimization scope and the number of parameters. We introduce a novel grid-based division of key cislunar regions and expand the constellation service area using a three-phase construction strategy. To evaluate the optimized constellation’s navigation capabilities, we test its performance with typical orbits, including Earth–Moon transfer orbit (EMTO), elliptical lunar orbits (ELO), and geosynchronous orbit (GEO). Experimental results show that a single near rectilinear halo orbit (NRHO) satellite provides single coverage of the Earth–Moon transfer critical region at sampling times, with an orbit determination (OD) accuracy of 475.7 m for the EMTO. Seven satellites, positioned on the <i>L</i>1, <i>L</i>2, <i>L</i>4, <i>L</i>5, and NRHO orbits, achieve quadruple coverage for both the Earth–Moon transfer and near-Moon regions, with OD accuracies of 25.7 and 17.3 m for the EMTO and ELO, respectively. In the third phase, adding two <i>L</i>3 LPO satellites forms a nine-satellite constellation, extending coverage across the entire cislunar space, achieving OD accuracies of 15.1, 13.4, and 2.2 m for the EMTO, ELO, and GEO, respectively. This study provides valuable insights for the future design and deployment of cislunar communication and navigation constellations.</p><div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":52291,"journal":{"name":"Astrodynamics","volume":"10 2","pages":"279 - 298"},"PeriodicalIF":6.5,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147751218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}