Loading...

Table of Content

    25 October 2014, Volume 34 Issue 5 Previous Issue    Next Issue
    For Selected: Toggle Thumbnails
    Attitude Pointing Adaptive Control of Intersatellite Laser Power Beaming
    YANG Ye-Wei, HUANG Yong, LI Xiao-Jiang
    2014, 34 (5):  1-9.  doi: 10.3780/j.issn.1000-758X.2014.05.001
    Abstract ( 1053 )   PDF (348KB) ( 1090 )   Save
    Basedonthebacksteppingtechnique,amethodwasproposedfordevelopinganattitudepointingadaptivecontrollerofintersatellitelaserpowerbeaming.ThemodifiedRodriguesparameterwasusedtodescribethesatelliteattitude,andtheexpectedattitudewascalculatedbytheattitudematrixtransformation.Consideringtheuncertaintiesinmomentofinertia,thelimitedinputsandexternaldisturbances,anadaptivecontrollawwasestablishedbasedontheattitudekinematicsequations.Finally,thesystemwasprovedsteadybytheLyapunov′sstabilitytheory.Thesimulationresultsshowthattheerrorsofattitudeandangularvelocityreachzeroin15 s.Boththeangularvelocityandthecontrollingmomentarekeptundercontrol.Therefore,theinitialattitudeoftheusersatellitecanbecontrolledtotheexpectedonebyusingthecontroller,andboththeangularvelocityandthecontrollingmomentcanbekeptundercontroliftheparameterisfitting.Thatprovesthecontrolleriseffectiveandfeasible.
    Related Articles | Metrics
    ReconfigurabilityEvaluationofMomentumWheelControlSystemUnderEnergyandReliabilityConstraints
    HU Yu-Sang, WANG Da-Yi, LIU Cheng-Rui
    2014, 34 (5):  10-17.  doi: 10.3780/j.issn.1000-758X.2014.05.002
    Abstract ( 1082 )   PDF (374KB) ( 1176 )   Save
    Since the energy consumption and system reliability constraint was rarely considered in the control system reconfigurability evaluation, the reconfigurability measurement and evaluation method were studied under the constraints for the satellite attitude control system. The control system model including the actuator failure factor was established. Based on the controllability Gramian Matrix, the reconfigurability measurement index under energy consumption was obtained. Furthermore, the control reconfigurability index was introduced into the system reliability constraint, which narrowed the set of reconfigurable systems. Finally, the combined index was obtained. From the control system with momentum wheels simulation, the reconfigurability comparison results among different constraints can be acquired. The results show that this evaluation method is effective.
    Related Articles | Metrics
    SSPS-OMEGA:ANewConcentratorSystemforSSPS
    YANG Yang, DUAN Bao-Yan, HUANG Jin, LI Xun, ZHANG Yi-Qun, FAN Jian-Yu
    2014, 34 (5):  18-23.  doi: 10.3780/j.issn.1000-758X.2014.05.003
    Abstract ( 2469 )   PDF (296KB) ( 1750 )   Save
    The concentrator system of the space solar power station (SSPS) has a dimension of km scale, which requires the knowledge of optics, mechanics, thermology, ontrol, and other disciplines. The existing concentrator schemes of the SSPS, such as the SSPS-ALPHA scheme, have the disadvantages of low efficiency and/or large fluctuation in solar concentration, large mass, and complicated control system. Thus,the SSPS scheme with high efficiency, light weight and simple control strategy was proposed. The SSPS-ALPHA scheme was analyzed, and then a new scheme called SSPS-OMEGA was presented under the premise of the same power hypothesis with the ALPHA scheme. With the same power collection of the ALPHA scheme, the proposed scheme has higher and more stable solar concentration efficiency, and the power-mass ratio is higher with 31.68%.
    Related Articles | Metrics
    Feature Reconstruction and Pose Determination for Large Space Target Based on Point Structured Light
    LIANG Bin, GAO Xue-Hai, XU Wen-Fu
    2014, 34 (5):  24-31.  doi: 10.3780/j.issn.1000-758X.2014.05.004
    Abstract ( 1272 )   PDF (347KB) ( 1779 )   Save
    A vision system of space robot can not observe a whole feature image of a large non-cooperative target to measure the relative position and attitude. To overcome this problem, a point structured light vision system composed by a point structured light and a single camera was established to determine the relative pose. An unknown size partial rectangular framework of the target was chosen as the measurement object. Firstly, themeasurement model of the point structured light vision system was built and the relationships were presented. Secondly, according to the intrinsic constraint of the point structured light vision system, a whole feature was reconstructed and four feature points were calculated. Thirdly, the relative transform matrix between the measurement system and the target was computed by the  four feature points. And the relative position and attitude was derived from the transform matrix. Finally, numerical simulations were studied to verify the method and the measurement errors were analysed. The results show that this method is effective.
    Related Articles | Metrics
    Relative Position and Velocity Error Covariance Analysis of Two Spacecraft in Lunar Orbit Rendezvous and Docking
    CHEN Shao-Wu, DONG Guang-Liang, FAN Min, LI Hai-Tao, HAO Wan-Hong
    2014, 34 (5):  32-40.  doi: 10.3780/j.issn.1000-758X.2014.05.005
    Abstract ( 1570 )   PDF (402KB) ( 1531 )   Save
    To establish steady relative navigation between two spacecraft in lunar orbit rendezvous and docking, accurate relative state determination between two spacecraft is needed in the long range ground based navigation. Same beam interferometry (SBI), as a high precision technology for relative angle measurement, is of great sigficant in the relative state determination. However, the systemmethodforanalyzing the influence of SBI on the relative states of two spacecraft in lunar orbit rendezvous was not developed. The information matrix of measurements with the relative states was deduced according to the covariance theory, and the model of the relative states error covariance was established. The simulation results show that the relative position and velocity errors are within the meter and millimeter per second under the current range, range rate, VLBI and SBI measurement errors. The error and its influence was obtained, and the influence of cycle ambiguity error on relative state error was analyzed. The resutls show that the cycle ambiguity of SBI reduce from 2 to 0, andthe relative position error on T and N is decreased greatly.
    Related Articles | Metrics
    Attitude Control Technology of Upper Stage During Orbital Transfer
    WANG Zhao-Hui, JIN Lei, JIA Ying-Hong, DUAN Jia-Jia
    2014, 34 (5):  41-48,55.  doi: 10.3780/j.issn.1000-758X.2014.05.006
    Abstract ( 1435 )   PDF (345KB) ( 1524 )   Save
    A method which providing three-axis attitude control by the gimbaled thruster gimbal and yaw attitude control thruster was proposed. Firstly, the multi-body dynamics equations with the upper stage body, gimbaled thruster and gimbal support were built based on the Kane equation. The gimbaled thruster′s disturbance torque and gimbal angle formulas when the gimbaled thruster working were derived. Sceondly, the upper stage attitude control law was designed based on the variable structure control law, that not only achieved 10-3 atttiude control precision, but allowed the gimbaled thruster′s thrust direction achieve the direction determined by the guidance system as well as was via the mass center of upper stage. Finally, the validity of the proposed method was verified by numerical simulations.
    Related Articles | Metrics
    Underactuated Spacecraft Attitude Hold Control Based on Bias Momentum Wheel
    GUO Chao-Li, WANG Shu-Yi, ZHANG Du-Zhou
    2014, 34 (5):  49-55.  doi: 10.3780/j.issn.1000-758X.2014.05.007
    Abstract ( 1001 )   PDF (298KB) ( 1451 )   Save
    To maintain the three axis attitude of the underactuated nadir-pointing spacecraft, an attitude hold control method based on the pitch-axis bias momentum wheel and roll-axis thruster was proposed.The method was based on coupling between the roll and yaw axes of biased-momentum spacecraft, and could avoid the problem that zero momentum spacecraft′s underactuated axis and actuated axis were almost decoupled. Spacecraft attitude dynamics was divided into long period dynamics and short period dynamics, and the control laws were designed by the pole assignment method. The scale of control parameters was confirmed, and the stable state error of the control system was obtained. The simulation results show that the designed controller can eliminate initial attitude error of the spacecraft and resist the external disturbance, and the spacecraft attitude is maintained at the equilibrium point.
    Related Articles | Metrics
    Motion Compensation Compressive Imaging in Optical Remote Sensing
    WANG Ze-Long, ZHU Ju-Bo, YAN Feng-Xia, LIU Ji-Ying
    2014, 34 (5):  56-63.  doi: 10.3780/j.issn.1000-758X.2014.05.008
    Abstract ( 1087 )   PDF (443KB) ( 1312 )   Save
    A compressive imaging method based on motion compensation was proposed to overcome the low-quality problem resulted from the motion of single-pixel imager. Firstly, the compressive sampling model with motion condition was built.Secondly, two image reconstructions, namely, frame-by-frame recovery and joint recovery, were analyzed. Meanwhile, its adaptability to different motion types as well as the distributions of its imaging quality was also discussed. The proposed method makes use of motion information to program the samples instead of reducing integrate time or sampling number,which avoids the decrease of imaging quality. Mathematical simulations and semi-physical experiments show that the proposed method has higher imaging quality than the imaging method without motion compensation.
    Related Articles | Metrics
    Study on Void Distribution Rule in Two-dimensional Quadrate Cavity of PCM Container
    JIAN Lu-Jing, ZHANG Jia-Xun, ZHAO Xin, HUO Yu-Hua
    2014, 34 (5):  64-70,78.  doi: 10.3780/j.issn.1000-758X.2014.05.009
    Abstract ( 921 )   PDF (325KB) ( 1205 )   Save
    To study the influence of the void on phase change heat transfer process under microgravity, the void model using temperature sorting algorithm was built based on the enthalpy method, which can simulate the interaction between the void and the temperature distribution. The 2D model of phase change material container was built to study the void migration rule under the periodical heat flux boundary condition. The results show that from the initial time to the 8th period the void disappears gradually in the low temperature region and appears in the high temperature region. The void moves to the high temperature region and diffuses along the isotherms. The void migration increases heat resistance along the heat transfer route and the temperature difference about 3℃ between cold and hot boundaries.
    Related Articles | Metrics
    AnalysisofSpacecraftField/WireCouplingBasedonImprovedFDTD/LumpedEquivalentSourceModel
    ZHANG Yu-Ting, ZHANG Hua
    2014, 34 (5):  71-78.  doi: 10.3780/j.issn.1000-758X.2014.05.010
    Abstract ( 1038 )   PDF (312KB) ( 1293 )   Save
    Aiming at the typical problems of electromagnetic pulse influencing wires of the spacecraft, the spacecraft field/wire coupling analysis model was built. To calculate the electromagnetic field, the finite difference time domain method was improved. The average electrical parameters was adopted, and the object edges was modified, which cannot match the Yee grids. To analyze the field/wire coupling, the multiconductor transmission line transient reponse model based on the lumped equivalent sources was proposed. The distributed voltage and current sources excited by the incident field were decoupled with the exponential multiconductor transmission lines matrix. The lumped equivalent voltage and current sources model were built. The model was used to analyze a wire in the launch vehicle which was influenced by the electromagnetic pulse. The analysis results show that the interference of the electromagnetic pulse to the wires can destroy the equipment, even though there is shield.
    Related Articles | Metrics
    OptimizationControlofBatteryRechargingBasedonSpaceInformationforGEOSatellite
    BIAN Bao-Gang, WANG Xin, FAN Heng-Hai, FANG Dong
    2014, 34 (5):  79-86.  doi: 10.3780/j.issn.1000-758X.2014.05.011
    Abstract ( 1036 )   PDF (345KB) ( 1219 )   Save
    The dynamic variation of the battery recharging efficiency of the satellite was studied, and the effects of the satellite orbit, attitude, the sun position, and the battery temperature on the performance degradation of GEO satellite battery were analyzed. The optimized calculating model was designed to predict the best battery recharging time. In-orbit application shows that the proposed method can improve the effective recharge capacity by 5 times, comparing with the automotive recharge. The problem of shortage battery is solved during the shadow period.
    Related Articles | Metrics
    PathPlanningforLunarRoverBasedonModifiedFruitFlyOptimizationAlgorithm
    MAO Zheng-Yang, FANG Qun, LI Ke-Xing, ZHANG Chuan-Xin
    2014, 34 (5):  87-93.  doi: 10.3780/j.issn.1000-758X.2014.05.012
    Abstract ( 1595 )   PDF (326KB) ( 1462 )   Save
    Given that fruit fly optimization algorithm was restricted for falling into local optima easily, the smell concentration judge value S in fruit fly optimization algorithm was modified for dynamic path planning on lunar surface. The optimizing performance for path planning between the fruit fly optimization algorithm and the particle swarm optimization algorithm was compared through the simulations. Results show that the path planning based on the modified fruit fly optimization algorithm has better instantaneity and can not fall into local optima easily. Finally, an avoidance strategy was proposed for avoiding the unknown static obstacles that the lunar rover encounters in a dynamic environment.
    Related Articles | Metrics