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Adaptive Quasi Fixed-Time Orbit Control Around asteroid with Performance Guarantees

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 89-107页

作者： Renyong Zhang Caisheng Wei Zeyang Yin Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing100094China School of Aeronautics and Astronautics Central South UniversityChangsha410083China School of Astronautics Northwestern Polytechnical UniversityXi’an710072China

This paper investigates a novel quasi fixed-time orbit tracking control method for spacecraft around an asteroid in the presence of uncertain dynamics and unknown *** quantitatively characterize the transient and steady-state responses of orbit tracking error system,a continuous performance function is devised via using a quartic ***,integrating backstepping control technique and barrier Lyapunov function leads to a quasi fixed-time convergent orbit tracking controller without using any fractional state information and symbolic ***,two groups of illustrative examples are employed to test the effectiveness of the proposed orbit control method.

关键词： Prescribed performance adaptive control orbital control asteroid

DIFFUSION CHARACTERS OF THE ORBITS IN THE asteroid MOTION

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Applied Mathematics and Mechanics(English Edition) 2001年第7期22卷 808-819页

作者：周礼勇孙义燧周济林 Department of Astronomy Nanjing University Nanjing 210093 P R China

A symplectic mapping is studied carefully. The exponential diffusion last, in developed chaotic region and algebraic law in mixed region were observed. An area was found where the diffusion follows a logarithmic law. It is shown in the vicinity of an island, the logarithm of the escape time decreases linearily as the initial position moves away from the island. But when approaching close to the island, the escape time goes up very quickly, consistent with the superexponential stability of the invariant curve. When applied to the motion of asteroid, this mapping's fixed points and their stabilities give an explanation of the distribution of asteroids. The diffusion velocities in 4:3, 3:2 and 2:1 jovian resonances are also investigated.

关键词： diffusion symplectic mapping asteroid

Target selection and transfer trajectories design for exploring asteroid mission

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Science China(Technological Sciences) 2010年第4期53卷 1150-1158页

作者： CUI PingYuan1,QIAO Dong1,CUI HuTao2 & LUAN EnJie3 1 School of Aerospace Engineering,Beijing Institute of Technology,Beijing 100081,China 2 Harbin Institute of Technology,Harbin 150001,China 3 National Defense Science and Industry Bureau,Beijing 100048,China 1. School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China2. Harbin Institute of Technology Harbin 150001 China3. National Defense Science and Industry Bureau Beijing 100048 China

Technique of target selection and profiles of transfer trajectory for Chinese asteroid exploring mission are studied systemically.A complete set of approaches to selecting mission targets and designing the transfer trajectory is ***,when selecting a target for mission,some factors regarded as the scientific motivations are ***,when analyzing the accessibility of targets,instead of the classical strategy,the multiple gravity-assist strategy is *** suitable and possible targets,taking into account scientific value and technically feasible,are obtained via selection and *** designing the transfer trajectory for exploring asteroid mission,an approach to selecting gravity-assist celestial body is ***,according to the mission constraints,the trajectory profile with 2-years △V-EGA for exploring asteroid is *** analyzing the trajectory profile,unexpected result that the trajectory would pass by two main-belts asteroids is ***,the original proposal is extended to the multiple flybys *** adds the scientific return for asteroid mission.

关键词： exploring asteroid target selection multiple flybys transfer trajectory

Phase space transport in a map of asteroid motion

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Communications in Nonlinear Science and Numerical Simulation 2000年第1期5卷 1-5页

作者： Liyong ZHOU Yisui SUN and Jilin ZHOU Department of Astronomy, Nanjing University, Nanjing 210093, China e-mail: buffalol @public1 .ptt.js. cn Department of Astronomy Nanjing University Nanjing 210093 China

We have studied the chaotic transport in a nonlinear model directly applicable to asteroid motion. An exponential and an algebraic diffusion law are observed in different regions of the phase space. We have also investigated the effects of small perturbations and found they can not only accelerate but also decelerate the transport.

关键词： phase space transport symplectic map asteroid

Dynamical behavior of flexible net spacecraft for landing on asteroid

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Astrodynamics 2021年第3期5卷 249-261页

作者： Yu Zhang Yang Yu Hexi Baoyin School of Aerospace Engineering Tsinghua UniversityBeijing 100084China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

A new era of up-close asteroid exploration has been entered in the 21st ***,the widely rugged terrain and microgravity field of asteroids still pose significant challenges to the stable landing of spacecraft and may even directly lead to the escape of the *** to the substantial energy dissipation arising from the interaction among multiple bodies,the flexible net,which is a typical multibody system,may be capable of overcoming the above *** this study,a dynamical model was established to analyze the movement of the flexible net spacecraft(FNS)near and on the asteroid ***,we investigated the dynamical environment of the target asteroid by combining the polyhedron method and spherical harmonics parametric surface modeling ***,we constructed the multibody dynamics model of the explorer using the linear Kelvin–Voigt ***,we studied the collision process between the FNS and asteroid based on the spring–damper contact dynamics *** trajectory and speed of the FNS could be derived by solving the system dynamic equations in ***,we analyzed the deformation,descent,jumping motion,and surface movement process of the FNS during the ***,a promising scheme is provided for asteroid exploration missions in the future.

关键词： asteroid flexible net energy dissipation multibody dynamics contact dynamics

Effects of solar radiation pressure on asteroid surface hopping transfers for high area/mass ratio rovers

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Research in Astronomy and Astrophysics 2021年第6期21卷 337-348页

作者： Chuan-Jun Dong Hong-Wei Yang Shuang Li Xue-Wen Liu College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The high area/mass ratio hopping rovers have potential applications in future asteroid surface *** paper systematically investigates the effects of solar radiation pressure(SRP)on ballistic surface hopping transfers for the asteroid 101955 *** of SRP on the traveled distance and the trajectory design of hopping transfers are analyzed and *** simulation results indicate that it is necessary to take SRP into account to ensure the success of hopping transfers and the proper use of SRP can help design the trajectories of hopping transfers with low initial impulses and short transfer *** also reveals the potential possibility in using SRP to control the post-hopping transfers with specific control policies in the future surface exploration of asteroids.

关键词： asteroid hopping solar radiation pressure dynamics trajectory

Stabilities of asteroid orbits in resonances

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Science China Mathematics 2002年第1期45卷 122-128页

作者：周礼勇周济林孙义燧 1. Department of Astronomy Nanjing University 210093 Nanjing China

A map of the asteroid motion is studied carefully. An exponential diffusion law in the chaotic sea and an algebraic law in the mixed region are observed. The effects of perturbations on diffusion are also discussed. The fixed points, their stabilities and the diffusion properties of the map give qualitative explanations of the distribution of asteroids, i.e. the depletion and accumulation of asteroids in the outer main belt, particularly in the first order mean motion resonances with Jupiter.

关键词： asteroid map diffusion.

A Tiny Piece of Basalt Probably from asteroid 4 Vesta

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Acta Geologica Sinica(English Edition) 2004年第5期78卷 1025-1033页

作者： LINYangting WANGDaode WANGGuiqing InstituteofGeologyandGeophysics ChineseAcademyofSciencesBeijing100090 GuangzhouInstituteofGeochemistry ChineseAcademyofSciencesGuangzhouGuangdong510640

Grove Mountains (GRV) 99018 is a new eucrite (0.23 g), consisting mainly of pyroxene (50.5 vol%) and plagioclase (37.2 vol%) with minor silica minerals (7.0 Vol%) and opaque minerals (5.2 vol%). It was intensely shocked, leading to partial melting, formation of abundant tiny inclusions in pyroxenes and plagioclase, and heavy brecciation. Exsolution of most pyroxenes (1-3μm in width of the lamellae), recrystallization of the shpck-induced melt pockets and veins (5-20μm in size), and homogeneous compositions of pyroxenes of various occurrences suggest the intense thermal metamorphism of GRV 99018 in the asteroidal body Vesta. This new eucrite will bring additional constraints on the chemical composition and multi-stage thermal and shock history of Vesta.

关键词： meteorite basalt eucrite asteroid magmatism shock metamorphism thermal history

Visual localization for asteroid touchdown operation based on local image features

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Astrodynamics 2020年第2期4卷 149-161页

作者： Yoshiyuki Anzai Takehisa Yairi Naoya Takeishi Yuichi Tsuda Naoko Ogawa The University of Tokyo Tokyo113-8654Japan RIKEN Center for Advanced Intelligence Project Tokyo103-0027Japan Japan Aerospace Exploration Agency Sagamihara252-5210Japan

In an asteroid sample-return mission,accurate position estimation of the spacecraft relative to the asteroid is essential for landing at the target *** the missions of Hayabusa and Hayabusa2,the main part of the visual position estimation procedure was performed by human operators on the Earth based on a sequence of asteroid images acquired and sent by the *** this approach is still adopted in critical space missions,there is an increasing demand for automated visual position estimation,so that the time and cost of human intervention may be *** this paper,we propose a method for estimating the relative position of the spacecraft and asteroid during the descent phase for touchdown from an image sequence using state-of-the-art techniques of image processing,feature extraction,and structure from *** apply this method to real Ryugu images that were taken by Hayabusa2 from altitudes of 20 km-500 *** is demonstrated that the method has practical relevance for altitudes within the range of 5-1 *** result indicates that our method could improve the efficiency of the ground operation in the global mapping and navigation during the touchdown sequence,whereas full automation and autonomous on-board estimation are beyond the scope of this ***,we discuss the challenges of developing a completely automatic position estimation framework.

关键词： visual navigation structure from motion asteroid touchdown Hayabusa2