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    25 October 2006, Volume 26 Issue 05 Previous Issue    Next Issue
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    Mathematical Method for Orbit Determination Based on GEOSTAR System
    Wang Jiongqi Zhou Haiyin Zhao Deyong Wu Yi(National University of Defense Technology,Changsha 410073)
    2006, 26 (05):  1-5+56. 
    Abstract ( 1739 )   Save
    Generally,it is impossible to determine the kinetic states of satellite only by twoGEOSTAR's tracking distance data.In order to do this work,some accessory information must be given,forexample several measurement data and dynamic model of satellite.The mathematical principle of GEOSTARsystem for orbit determination is analyzed.By applying range measurement data fusion and integrating thedynamic model,the trajectory of the user satellite was achieved.Simultaneously,the transfer relation of er-ror was put forward.This method doesn't need the referenced orbit of satellite,so it is very convenient.Theoretical analysis and simulation calculation prove that this method is more feasible and precise.
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    Improved Generalized Side-lobe Cancellation Beam-forming Algorithm
    Zhang Xiaofei Xu Kun Xu Dazhuan(Electronic Engineering Department,Nanjing University of Aeronautics and Astronautics,Nanjing 210016)
    2006, 26 (05):  6-9+42. 
    Abstract ( 1878 )   Save
    The generalized side-lobe cancellation beam-forming based on the eigen-struture was proposed to overcome the disadvantage of the traditional GSC beam-forming.Simulation results reveal that this algorithm has the better beam-forming perfomance than conventional adaptive beam-forming algorithm in the lower,middle and high signal-noise-ratio SNR,and it has robust characteristic and the better perfomance.
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    Control Method Research of Space Manual-control Rendezvous and Docking
    Hu Haixia Xie Yongchun(Beijing Institute of Control Engineering,Beijing 100080)
    2006, 26 (05):  10-16+49. 
    Abstract ( 1741 )   Save
    The pilot on the chaser spacecraft manipulates the stick to dock by the camera- assisted view of the target.In order to release the pilot's pressure and guarantee the success of RVD,the pilot is only in charge of the control of relative position while the chaser's attitude is kept consistent with the target's by automatic control system.The relative position control strategy and method of the pilot are proposed.The all-coefficient adaptive control and PID control Method are applied to the relative attitude control.The result indicates the allcoefficient adaptive control is better to the pilot's relative position control because of its small overshoot and fast slew maneuver.
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    Numerical Model Study of Thermal Analysis on Multilayer Perforated Insulation Material in Orbit
    Li PengXiao ZejuanCheng Huier(Shanghai Jiao Tong University,Shanghai 200030)
    2006, 26 (05):  17-20+36. 
    Abstract ( 1877 )   Save
    The combined radiation and conduction heat transfer in multilayer perforated insulation material MLPIM in orbit were investigated.The energy equation of the reflective screen was established.Combining the finite differential method the model for transient temperature calculation of the reflective screens in MLPIM and the model of inner radiation were presented.The space environment was looked as a screen in the whole model,which was convenient to deal with the boundary condition.Comparing the calculational result with the model to the calculational and experimental result in the reference at the analogical conditions it was proved that the model was feasible to apply in the engineering.The calculational result in another example shows the characteristics of the transient temperature and heat flux of the MLPIM in orbit and the characteristics of the temperature distribution of the reflective screens.This model provides the theoretical basis for the thermal performance study and optimum design of perforated multilayer insulation material.
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    Influence of Formation Flying Satellites Spatial State Parameters Estimate to Velocity Precision in ATI
    Wang ZhiyuanYi DongyunYao Jing(Science College,National University of Defense Technology,Changsha 410073)
    2006, 26 (05):  21-28. 
    Abstract ( 1735 )   Save
    Based on the analysis of the characteristic parameters which have influence on the radical velocity precision,two mathematical association models were established.One was between spatial state parameters estimate and characteristic parameters,another was between characteristic parameters and radical velocity precision.By simulation,characteristic parameters precision in different scenarios,error propagation matrix and the precision factors of measurement error propagation relation were obtained,and the influence of formation flying satellites spatial state parameters estimate to radical velocity precision was investigated finally.
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    Cooperative Control of Two Flexible Manipulators Manipulating a Common Rigid Object
    Lei Yongjun Wu Hongxin(Beijing Institute of Control Engineering,Beijing 100080)
    2006, 26 (05):  29-36. 
    Abstract ( 1694 )   Save
    With load distribution the control of two flexible manipulators manipulating a common rigid object is reduced into the individual control of two equivalent flexible manipulators.Meanwhile,it is demonstrated that the equivalent flexible manipulator has the same dynamic property as the actual flexible manipulator.The desired trajectory of each equivalent flexible manipulator is solved with the corresponding equivalent rigid manipulator respectively.And then,the controller of each manipulator for both trajectory approximately tracking and internal force regulating is designed respectively using the output redefinition.At last,a numerical simulation is performed on two flexible manipulators moving a common rigid object,and the results illustrate the efficiency of the proposed approach in the design of the cooperative controller of flexible multi- manipulator.
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    Relative Motion of Leader-follower Formation on Circular Orbit
    Xue DanCao XibinWu Yunhua(Research Center of Satellite Technology,Harbin Institute of Technology,Harbin 150080)
    2006, 26 (05):  37-42. 
    Abstract ( 1784 )   Save
    A group of relative motion equations were given with the Keplerian motion assumption,which was proved to be true in physical concept.On the basis of these equations,an efficient approach for relative navigation of satellites flying in formation through inter-satellite measurements was developed,and an EKF was designed to estimate the orbit states of slave satellite.The simulation results verify the validity of these equations and the navigation method.
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    Influence of Aerodynamic Force on a Parachute's Oscillation in Steady Descent
    Liao Qianfang~1 Liao Bo~2 Cheng Wenke~1 Song Xumin~1(1 National University of Defense Technology,Changsha 410073)(2 Second Artillery Equipment Academe,Beijing 100085)
    2006, 26 (05):  43-49. 
    Abstract ( 1708 )   Save
    A five degrees of freedom model of the parachute-load system is performed to analyze its dynamic stability in steady descent,and the distinct differentia of the oscillations are found under different aerodynamic forces through a simulation,the influence of aerodynamic parameters on the system's oscillation angle and frequency is discussed emphatically.
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    Influence Analysis of the Spacing among the Apparatus and Equipments on the Flow and Heat Transfer inside the Spacelab Racks
    Jian Lujing Zhang Jiaxun(China Academy of Space Technology,Beijing 100094)
    2006, 26 (05):  50-56. 
    Abstract ( 1736 )   Save
    In order to make the best of the limited space in the rack to improve the heat dissipation environments of the apparatus,an analytical model of the spacelab rack was established.And by using numerical methods,the flow fields and the temperature fields inside the rack under diverse spacing of the apparatus were received.The average flow velocity and average convective heat exchange coefficient were also studied.The heat dissipation characteristics can be improved effectively by designing the spacing of the apparatus in suitable range, and this can provide the references to thermal design of racks mounted in spacelab
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    Optical Performance for CCD Optical Sensor of Rendezvous and Docking in Space
    Liu Xiaojun~(1) Ni Guoqiang~(1) Lu Xin~(2) Wang Yu~(3) Wei Zhijun~(3)(1 Beijing Institute of Technology,Beijing 100081)(2 Beijing Institute of Control Engineering,Beijing 100083)(3 National Institute of Metrology,Beijing 100013)
    2006, 26 (05):  57-63. 
    Abstract ( 1678 )   Save
    With radiometry as a standard,cooperative targets opto-power models and equation of CCD camera detection were established.The restrictive relationship between cooperative targets opto-power and CCD camera parameters was obtained.Imaging definition which CCD camera works in limited distance was solved by using hyperfocal distance.Telecentric optical system was employed in order to solve the precision of measuring systems.The relationship of pixel number CCD camera detect and operating distance was analyzed.It is studied what influences CCD camera when the sun radiates FOV of CCD camera and mechanic part of docking reflects from the sun.
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    Design and Analysis of the Transition Phase from Absolute Navigation to Relative Navigation in Spacecraft Rendezvous Mission
    Zhu Renzhang Lin Yan(Beijing University of Aeronautics and Astronautics,Beijing 100083)
    2006, 26 (05):  64-70. 
    Abstract ( 1657 )   Save
    Subject to the homing and phasing maneuvers as well as constraints of the maximal link distance of the relative navigation,the limited liaison time of the relative navigation and the maximal delay permitted by the crew schedule.For various homing maneuver modes,the relationship between the velocity error from the phasing maneuver and the dispersion zone of the initial point of the drift phase were established,and the dispersion zone of the nominal position of the initial point of the drift phase were given.
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