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Robust extended Kalman filter with input estimation for maneuver tracking

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Chinese Journal of Aeronautics 2018年第9期31卷 1910-1919页

作者： Yuzi JIANG hexi baoyin School of Aerospace Engineering Tsinghua University

This study investigates the problem of tracking a satellite performing unknown continuous maneuvers. A new method is proposed for estimating both the state and maneuver acceleration of the satellite. The estimation of the maneuver acceleration is obtained by the combination of an unbiased minimum-variance input and state estimation method and a low-pass filter. Then a threshold-based maneuver detection approach is developed to determinate the start and end time of the unknown maneuvers. During the maneuvering period, the estimation error of the maneuver acceleration is modeled as the sum of a fluctuation error and a sudden change error. A robust extended Kalman filter is developed for dealing with the acceleration estimate error and providing state estimation. Simulation results show that, compared with the Unbiased Minimum-variance Input and State Estimation(UMISE) method, the proposed method has the same position estimation accuracy, and the velocity estimation error is reduced by about 5 times during the maneuver period. Besides, the acceleration detection and estimation accuracy of the proposed method is much higher than that of the UMISE method.

关键词： Extended Kalman filters Input estimation Maneuver detection Maneuver tracking Orbit determination

A new physical model on the capillary phenomenon of granular particles

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Applied Mathematics and Mechanics(English Edition) 2019年第1期40卷 127-138页

作者： Nan ZHANG Bin CHENG hexi baoyin Department of Aerospace Engineering Tsinghua University

Similar to the capillary phenomenon of liquid, granular particles can move up to a certain height along a vertically vibrating tube. The certain height, which is called the equilibrium height, is related to some parameters, e.g., the inner diameter of the tube, the amplitude, and the vibration frequency. In this paper, a theoretical model is proposed to explain the physical origin of the capillary phenomenon and the effects of the inner diameter of the tube, the amplitude, and the vibration frequency on the equilibrium height. In this model, the volumes of the inflowing and outflowing particles in a vibration period are calculated, which can significantly broaden our understanding in the flow of particles in the bottom of the tube. In order to prove the assumption of this physical model that the particles in the bottom of the tube move in the form of sine, several experiments are conducted. The granular climbing heights at different granular positions and different time stages are measured. The results show that granules move in the form of sine, which almost coincides with the motion of the tube. Moreover, motivated by the sampling on the asteroid regolith based on this mechanism, the sampling efficiencies for various vibration amplitudes and frequencies are discussed based on the new proposed model. It is found that there is an optimum frequency at which sampling is the most effective.

关键词： granular matter vertical vibration nonlinear dynamics theoretical analysis

Solar sail attitude control using shape variation of booms

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Chinese Journal of Aeronautics 2022年第10期35卷 326-336页

作者： Feng ZHANG Shengping GONG Haoran GONG hexi baoyin School of Aerospace Engineering Tsinghua UniversityBeijing 100084China School of Astronautics Beihang UniversityBeijing 100083China

Active attitude control of solar sails is required to control the direction of the force generated by Solar Radiation Pressure(SRP). It is desirable to control the attitude through propellantfree means. This paper proposes a new method for attitude control of solar sails: A boom consisting of "smart" structural material can be deformed by the piezoelectric actuator, and Solar Radiation Pressure torque will be generated due to shape variation of sail membrane caused by boom deformation. The method has the advantages of simple structure, small disturbance and small additional load, and is not limited by the size of the solar sail. The case of rendezvous with the Asteroid 2000SG344 is used to verify the attitude control around the pitch and yaw axes.

关键词： Attitude control Boom deformation Dynamics Solar radiation pressure Solar sail

Design and optimization of a trajectory for Moon departure Near Earth Asteroid exploration

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Science China(Physics,Mechanics & Astronomy) 2011年第4期54卷 748-755页

作者： CHEN Yang baoyin hexi LI JunFeng School of Aerospace Tsinghua University Beijing 100084 China

The lunar probe often has some remaining fuel on completing the predefined Moon exploration mission and may carry out some additional tasks from the Moon orbit using the *** possibility for the lunar probe to escape from the Moon and the Earth is *** and optimization of the trajectory from the Moon orbit to the Near Earth Asteroids (NEAs) using the spacecraft's residual fuel is *** first,the semi-major axis,inclinations and the phase relations with the Earth of all the numbered NEAs are investigated to preliminarily select the possible *** on the Sun-centered two-body problem,the launch window and the asteroid candidates are determined by calculating the minimum delta-v for two-impulse rendezvous mission and one-impulse flyby mission,*** a precise designed trajectory,a full ephemeris dynamical model,which includes gravities of the Sun,the planets and the Moon,is adopted by reading the JPL *** departure time,arrival time,burning time duration and thrust angles are set as variables to be designed and *** optimization problem is solved via the Particle Swarm Optimization (PSO) ***,two feasible NEA flyby missions are presented.

关键词： trajectory design full ephemeris model Near Earth Asteroid exploration Particle Swarm Optimization

Formation reconfiguration in restricted three body problem

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Acta Mechanica Sinica 2007年第3期23卷 321-328页

作者： Shengping Gong Junfeng Li hexi baoyin Yunfeng Gao School of Aerospace Tsinghua UniversityBeijing 100084 China

Reconfiguration of formation flying around a halo orbit of the Sun-Earth restricted three body system is investigated with impulse maneuvers. For a short time reconfiguration, the two-impulse maneuver is investigated with both analytical and numerical methods and the Beginning-Ending （BE） method is proven to be an energy-optimal one of all two-impulse （TI） reconfigurations, and the energy consumption of BE is independent of the position of the chief spacecraft, and decreases with the reconfiguration time. Then, genetic algorithm is adopted to optimize the energy consumption. The results show that the optimal energy increases with radius difference between the initial and final orbits, and decreases with the reconfiguration time.

关键词： Three body problem Halo orbit Formation reconfiguration Formation flying

Entropy method of measuring and evaluating periodicity of quasi-periodic trajectories

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Science China(Physics,Mechanics & Astronomy) 2018年第6期61卷 30-49页

作者： Yanshuo Ni Konstantin Turitsyn hexi baoyin Junfeng Li School of Aerospace Engineering Tsinghua University Department of Mechanical Engineering Massachusetts Institute of Technology

This paper presents a method for measuring the periodicity of quasi-periodic trajectories by applying discrete Fourier transform （DFT） to the trajectories and analyzing the frequency domain within the concept of entropy. Having introduced the concept of entropy, analytical derivation and numerical results indicate that entropies increase as a logarithmic function of time. Periodic trajectories typically have higher entropies, and trajectories with higher entropies mean the periodicities of the motions are stronger. Theoretical differences between two trajectories expressed as summations of trigonometric functions are also derived analytically. Trajectories in the Henon-Heiles system and the circular restricted three-body problem （CRTBP） are analyzed with the indicator entropy and compared with orthogonal fast Lyapunov indicator （OFLI）. The results show that entropy is a better tool for discriminating periodicity in quasiperiodie trajectories than OFLI and can detect periodicity while excluding the spirals that are judged as periodic cases by OFLI. Finally, trajectories in the vicinity of 243 Ida and 6489 Golevka are considered as examples, and the numerical results verify these conclusions. Some trajectories near asteroids look irregular, but their higher entropy values as analyzed by this method serve as evidence of frequency regularity in three directions. Moreover, these results indicate that applying DFT to the trajectories in the vicinity of irregular small bodies and calculating their entropy in the frequency domain provides a useful quantitative analysis method for evaluating orderliness in the periodicity of quasi-periodic trajectories within a given time interval.

关键词： quasi-periodic trajectories entropy quality evaluating

Coupled trajectory and attitude stability of displaced orbits

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Acta Mechanica Sinica 2010年第1期26卷 127-140页

作者： hexi baoyin Junfeng Li School of Aerospace Tsinghua University 100084 Beijing China

Coupled trajectory and attitude stability of displaced solar orbits is studied by using sailcraft with a kind of two-folding construction with two unequal rectangular plates forming a right angle. Three-dimensional coupled trajectory and attitude equations are developed for the coupled dynamical system, and the results show that all three types of displaced solar orbits widely referenced can be achieved through selecting an appropriate size of the two-folding sail. An anal- ysis of the corresponding linear stability of the trajectory and attitude coupled system is carried out, and both trajectory and attitude linearly stable orbits are found to exist in a small range of parameters, whose non-linear stability is then examined via numerical simulations. Finally, passively stable orbits are found to have weak stability, and such passive means of station-keeping are attractive and useful in practice because of its simplicity.

关键词： Solar sail Displaced solar orbit Coupled trajectory and attitude stability Passive station-keeping

Timeline Club:An optimization algorithm for solving multiple debris removal missions of the time-dependent traveling salesman problem model

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Astrodynamics 2022年第2期6卷 219-234页

作者： Nan Zhang Zhong Zhang hexi baoyin School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

With the increase of space debris,space debris removal has gradually become a major issue to address by worldwide space *** debris removal missions,in which multiple debris objects are removed in a single mission,are an economical approach to purify the space *** missions can be considered typical time-dependent traveling salesman problems(TDTSPs).In this study,an intelligent global optimization algorithm called Timeline Club Optimization(TCO)is proposed to solve multiple debris removal missions of the TDTSP *** adopts the traditional ant colony optimization(ACO)framework and replaces the pheromone matrix of the ACO with a new structure called the Timeline *** Timeline Club records which debris object to be removed next at a certain moment from elitist solutions and decides the probability criterion to generate debris sequences in new *** hypothetical scenarios,the Iridium-33 mission and the GTOC9 mission,are considered in this *** results show that TCO offers better performance than those of beam search,ant colony optimization,and the genetic algorithm in multiple debris removal missions of the TDTSP model.

关键词： Timeline Club global optimization multiple debris removal time-dependent traveling salesman problem(TDTSP)

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