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Autonomous navigation of an asteroid orbiter enhanced by a beacon satellite in a high-altitude orbit

Astrodynamics 2024年第3期8卷 375-400页

作者： Weidong Yin Yu Shi Leizheng Shu Yang Gao University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing100094China

This study aims to assess the autonomous navigation performance of an asteroid orbiter enhanced using an inter-satellite link to a beacon *** navigation includes the orbit determination of the orbiter and beacon,and asteroid gravity estimation without any ground station *** measurements were acquired using satellite-to-satellite tracking(SST)and optical observation of asteroid surface *** study presents a new orbiter-beacon SST scheme,in which the orbiter circumnavigates the asteroid in a low-altitude strongly-perturbed orbit,and the beacon remains in a high-altitude weakly-perturbed *** used Asteroid 433 Eros as an example,and analyzed and designed low-and high-altitude orbits for the orbiter and *** navigation measurements were precisely modeled,extended Kalman filters were devised,and observation configuration was analyzed using the Cramer-Rao lower bound(CRLB).Monte Carlo simulations were carried out to assess the effects of the orbital inclination and altitudes of the orbiter and beacon as key influencing *** simulation results showed that the proposed SST scheme was an effective solution for enhancing the autonomous navigation performance of the orbiter,particularly for improving the accuracy of gravity estimation.

关键词： asteroid exploration gravity estimation orbit determination satellite-to-satellite tracking(SST) optical observation

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Close relative motion on distant retrograde orbits

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Chinese Journal of Aeronautics 2023年第3期36卷 335-356页

作者： Chihang YANG Ming WANG Hao ZHANG University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing 100094China

Distant Retrograde Orbits(DROs)in the Earth-Moon system have great potential to support varieties of missions due to the favorable stability and orbital ***,the close relative motion on DROs should be analyzed to design formations to assist or extend the DRO ***,as the reference DROs are obtained through numerical methods,the close relative motions on DROs are non-analytical,which severely limits the design of relative *** this paper,a novel approach is proposed to construct the analytical solution of bounded close relative motion on *** linear dynamics of relative motion on DRO is established at *** preliminary forms of the general solutions are obtained based on the Floquet *** the general solutions are classified as different modes depending on their periodic components.A new parameterization is applied to each mode,which allows us to explore the geometries of quasi-periodic modes in *** each mode,the solutions are integrated as a uniform expression and their periodic components are expanded as truncated Fourier *** this way,the analytical bounded relative motion on DRO is *** on the analytical expression,the characteristics of different modes are comprehensively *** natural periodic mode is always located on the single side of the target spacecraft on DRO and is appropriate to be the parking orbits of the rendezvous and *** the basis of quasi-periodic modes,quasi-elliptical fly-around relative trajectories are designed with the assistance of only two impulses per *** fly-around formation can support observations to targets on DRO from multiple viewing *** the fly-around formation is validated in a more practical ephemeris model.

关键词： Distant retrograde orbits Ephemeris model Floquet theory Formation flight Relative motion spacecraft Three-body problem Transfer singularity

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Improved sliding mode synchronous tracking control of dual linear motor based on manipulation efficiency learning 7

Improved sliding mode synchronous tracking control of dual l...

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7th IEEE International Electrical and Energy Conference, CIEEC 2024

作者： Li, Minghuang Cai, Zhiwei Wang, Zhe Guo, Ruicheng Zhang, Yongkang Zhang, Jianquan Technology and Engineering Center for Space Utilization University of Chinese Academy of Sciences Beijing China Technology and Engineering Center for Space Utilization Beijing China

ISBN: (纸本)9798350359558

In order to improve the microgravity level of the 4-second electromagnetic launch micro-gravity experimental device, in this paper, based on the vector control system of a dual linear induction motor, a new dual controller separation, and complementary control strategy are proposed to improve the synchronous performance of the dual motor. At the same time, an improved sliding mode controller (MEL-SMC) based on manipulation efficiency learning is designed to compensate for the error of position tracking in the inner capsule. Finally, the algorithm is written into the controller of the 4-second electromagnetic launch micro-gravity experimental device, which verifies the effectiveness of the control strategy and provides a high-precision microgravity environment. © 2024 IEEE.

关键词： Microgravity

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A review of periodic orbits in the circular restricted three-body problem

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Journal of Systems engineering and Electronics 2022年第3期33卷 612-646页

作者： ZHANG Renyong Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing 100094China

This review article aims to give a comprehensive review of periodic orbits in the circular restricted three-body problem(CRTBP),which is a standard ideal model for the Earth-Moon system and is closest to the practical mechanical *** focuses the attention on periodic orbits in the Earth-Moon *** work is primarily motivated by a series of missions and plans that take advantages of the three-body periodic orbits near the libration points or around two gravitational celestial ***,simple periodic orbits and their classification that is usually considered to be early work before 1970 are summarized,and periodic orbits around Lagrange points,either planar or three-dimensional,are intensively studied during past ***,stability index of a periodic orbit and bifurcation analysis are presented,which demonstrate a guideline to find more periodic orbits inspired by bifurcation ***,the practical techniques for computing a wide range of periodic orbits and associated quasi-periodic orbits,as well as constructing database of periodic orbits by numerical searching techniques are also *** those unstable periodic orbits,the station keeping maneuvers are ***,the applications of periodic orbits are presented,including those in practical missions,under consideration,and still in conceptual design *** review article has the function of bridging between engineers and researchers,so as to make it more convenient and faster for engineers to understand the complex restricted three-body problem(RTBP).At the same time,it can also provide some technical thinking for general researchers.

关键词： periodic orbit restricted three-body problem classi-fication orbit family bifurcation

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AdaPIP: Adaptive picture-in-picture guidance for 360° film watching

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Computational Visual Media 2024年第3期10卷 487-503页

作者： Yi-Xiao Li Guan Luo Yi-Ke Xu Yu He Fang-Lue Zhang Song-Hai Zhang Department of Computer Science and Technology Tsinghua UniversityBeijingChinaand Beijing National Research Center for Information Science and Technology(BNRist)Tsinghua UniversityBeijingChina Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijingChina Victoria University of Wellington WellingtonNew Zealand

360°videos enable viewers to watch freely from different directions but inevitably prevent them from perceiving all the helpful *** mitigate this problem,picture-in-picture(PIP)guidance was proposed using preview windows to show regions of interest(ROIs)outside the current view *** identify several drawbacks of this representation and propose a new method for 360° film watching called *** enhances traditional PIP by adaptively arranging preview windows with changeable view ranges and *** addition,AdaPIP incorporates the advantage of arrow-based guidance by presenting circular windows with arrows attached to them to help users locate the corresponding ROIs more *** also adapted AdaPIP and Outside-In to HMD-based immersive virtual reality environments to demonstrate the usability of PIP-guided approaches beyond 2D *** user experiments on 2D screens,as well as in VR environments,indicate that AdaPIP is superior to alternative methods in terms of visual experiences while maintaining a comparable degree of immersion.

关键词： 360°videos picture-in-picture(PIP) virtual reality(VR) visual guidance

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Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2025年第1期68卷 195-207页

作者： Peng ZHANG Xin LIU Guanghui LIU Wei DAI Hanzhe YANG Haibo ZHENG Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG Guang ZHANG Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing100094China Beijing Hegong Simulation Co. LtdBeijing100089China

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration *** classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar *** this study,we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation *** scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic *** modeling of the dry magnetic separation device is conducted,and the three-dimensional distribution of magnetic parameters is calculated and *** on the characterization and analysis of the Chang E-5's samples,the morphologies and physical parameters of lunar regolith particles are modeled and simulated.A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed,and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are *** results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum ***,we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process,showing that these factors can obviously enhance the beneficiation process of lunar *** study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith,providing a theoretical basis for the scientific tasks of collecting,processing,and utilizing lunar mineral resources.

关键词： Lunar regolith In-situ resource utilization Magnetic separation Classified sampling

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A multi-frame sparse self-learning PWC-Net for motion estimation in satellite video scenes

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Science China(Information Sciences) 2023年第9期66卷 213-225页

作者： Tengfei WANG Yanfeng GU Shengyang LI School of Electronics and Information Engineering Harbin Institute of Technology Technology and Engineering Center for Space Utilization Chinese Academy of Sciences University of Chinese Academy of Sciences

Motion estimation is an important approach to acquiring motion information of all targets in satellite video while it provides the ability to real-time monitor the Earth observation region. Compared with the case in computer vision, motion estimation in satellite video has to face two main difficulties: the large scale of observation and numerous weak targets of low signal-to-noise ratio. In this paper, a multi-frame sparse self-learning PWC-Net(MSSPWC-Net) is proposed to implement motion estimation of the weak targets in satellite video. To overcome the shortage that the existing PWC-Net fails to extract motion information from numerous weak targets, motion consistency and sparse self-learning are introduced to modify the pyramid,warping, and cost volume convolutional neural networks(CNN) network(PWC-Net). The motion consistency between neighboring frames as a multi-frame framework is mainly used to improve the accuracy of motion estimation of the weak targets, and sparse self-learning is adopted to deal with the case that labeled samples in satellite video are insufficient to train PWC-Net. Numerical experiments are conducted on 4 real satellite video datasets. Experimental results demonstrate that the proposed MSSPWC-Net achieves the excellent performance of motion estimation of the weak targets in satellite video and outperforms the state-of-the-art methods.

关键词： satellite video scenes motion estimation small blurry targets

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Overview of the Lunar In Situ Resource utilization Techniques for Future Lunar Missions

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space(Science & technology) 2023年第1期3卷 293-310页

作者： Peng Zhang Wei Dai Ran Niu Guang Zhang Guanghui Liu Xin Liu Zheng Bo Zhi Wang Haibo Zheng Chengbao Liu Hanzhe Yang Yifan Bai Yang Zhang Dong Yan Kefa Zhou Ming Gao Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing 100094China

Along with the rapid development of space technology,extraterrestrial exploration has gradually tended to further-distanced and longer-termed planet *** the first step of an attempt for humans to build a perpetual planet base,building a lunar base by in situ resource utilization(ISRU)will drastically reduce the reliance of supplies from *** resources including mineral resources,water/ice resources,volatiles,and solar energy will contribute to the establishment of a lunar base for long-term life support and scientific exploration missions,although we must consider the challenges from high vacuum,low gravity,extreme temperature conditions,*** article provides a comprehensive review of the past developing processes of ISRU and the latest progress of several ISRU technologies,including in situ water access,in situ oxygen production,in situ construction and manufacture,in situ energy utilization,and in situ life support and plant cultivation on the *** being able to provide some material and energy supplies for lunar base construction and scientific exploration,the ISRU technologies need continuous validation and upgrade to satisfy the higher requirements from further lunar exploration ***,a 3-step development plan for lunar ISRU technologies in the next decade is proposed,which consists of providing technological solutions,conducting technical verification on payloads,and carrying out in situ experiments,with the ultimate aim of establishing a permanent lunar station and carrying out long-term lunar surface scientific *** overview of ISRU techniques and our suggestions will provide potential guidance for China’s future lunar exploration missions.

关键词： planet payload lunar

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MTCR-CR Routing Strategy for Connection-Oriented Routing over Satellite Networks

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China Communications 2024年第5期21卷 280-296页

作者： Li Changhao Sun Xue Yan Lei Cao Suzhi The University of Chinese Academy of Sciences Beijing 100094China Key Laboratory of Space Utilization Chinese Academy of SciencesBeijing 100094China Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing 100094China

The high-speed movement of satellites makes it not feasible to directly apply the mature routing scheme on the ground to the satellite ***-DVTR in the snapshot-based connectionoriented routing strategy is one of the representative solutions,but it still has room for improvement in terms of routing *** this paper,we propose an improved scheme for connection-oriented routing strategy named the Minimal Topology Change Routing based on Collaborative Rules(MTCR-CR).The MTCR-CR uses continuous time static topology snapshots based on satellite status to search for intersatellite link(ISL)construction solutions that meet the minimum number of topology changes to avoid route *** simulation results in Beidou-3 show that compared with DT-DVTR,MTCR-CR reduces the number of routing changes by about 92%,the number of path changes caused by routing changes is about38%,and the rerouting time is reduced by approximately 47%.At the same time,in order to show our algorithm more comprehensively,the same experimental index test was also carried out on the Globalstar satellite constellation.

关键词： ISL routing stability satellite networks satellite routing dynamic strategy

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Research on Adaptive Model Pooling Method for Data Stream Anomaly Detection Based on Variational Auto-Encoder

Research on Adaptive Model Pooling Method for Data Stream An...

引用

2024 China Automation Congress, CAC 2024

作者： Li, Mingwei Fan, Zimeng Song, Lei Guo, Lili Key Laboratory of Space Utilization Technology and Engineering Center for Space Utilization Chinese Academy of Sciences University of Chinese Academy of Sciences Beijing China Key Laboratory of Space Utilization Technology and Engineering Center for Space Utilization Chinese Academy of Sciences Beijing China

ISBN: (纸本)9798350368604

Abnormal detection is vital for fault warning in industrial production and safety in daily life. However, the challenge of constantly evolving data streams, influenced by external factors and performance degradation, presents a significant hurdle in this regard. Unfortunately, existing anomaly detection methods are unable to cope with these issues effectively. The models are unable to adapt to data streams with constantly changing distributions, which results in poor anomaly detection performance. To address this problem, this paper proposes VAE-ARCUS, an adaptive model pooling online abnormal detection method based on variational autoencoders. This is achieved by modifying the original autoencoder model, which is implemented within the ARCUS framework, into a variational autoencoder. This enables the model to achieve greater accuracy and to grasp the characteristics of the data distribution more effectively, thus alleviating the issues associated with the overfitting of the base autoencoder model to noisy data. Finally, experimental results conducted on six high-dimensional and concept drift datasets show that the model outperforms other autoencoder-based models and common stream anomaly detection methods in detecting anomalies and generalizing the model's capabilities. © 2024 IEEE.

关键词： Signal encoding

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