#### Table of Content

25 August 2000, Volume 20 Issue 04
 Finiteness of Singular Points in a Certain Kind of Single Gimbal Control Moment Gyroscope Systems Wu Zhong Wu Hongxin (Beijing Institute of Control Engineering,Beijing 100080) Chou Wusheng (Beijing University of Aeronautics and Astronautics,Beijing 100083) 2000, 20 (04):  .  Abstract ( 1714 )   Single Gimbal Control Moment Gyroscopes (SGCMGs) are torque produ cing devices which are internal to a spacecraft and operate based on principles of momentum exchange.Normally,three or more SGCMGs are used in the spacecraft in order to realize 3 axis control.However,SGCMG systems do suffer from a serious drawback-singularity sometimes,and can not produce desired control torque when many SGCMGs work coordinately.In order to avoid system singularity,distribution of singular points must be studied in gimbal space for SGCMG systems.In this paper,it is proved that the correspondent singular points in gimbal space are finite to any point in angular momentum space for redundant systems which axes are mounted non coplanarly,pyramidally and symmetrily.
 Data Fusion Method on Orbit Determination Using GEOSTAR System Zhou Hongchao Wang Zhengming (National University of Defence Technology,Changsha 410073) 2000, 20 (04):  .  Abstract ( 1647 )   A third positioning parameter is requisite for GEOSTAR system.GEOSTAR system and multiple existent shooting range tracking system are synthesized.By applying data fusion method,positioning and speed parameters are achieved.Meanwhile,system error of GEOSTAR and shooting range tracking system are presented.Theoretical analysis and simulation calculation prove that the method is more precisive.
 The Simulation Test for Gauging Liquid Propellant Remaining on a Satellite Zhang Tianping Da Daoan Cheng Bin Li Yuhong Liu Zhidong Huo Hongqing (Lanzhou Institute of Physics,Lanzhou 730000) 2000, 20 (04):  .  Abstract ( 1817 )   The ground simulation test for gauging liquid propellant remaining on a satellite is introduced.The test results obtained from the isothermal model are presented in details,mainly including the transient characteristics of the pressure and temperature,the measurement accuracy and its relation with other factors.The possibility that the accuracy is better than 1% of the total tank volume is indicated,and some related problems are discussed.
 An Object-Oriented Analysis Method for Liquid Rocket Engine System Huang Weidong (Naval Academy of Aeronautical Engineering,Yantai 264001) Wang Kechang Chen Qizhi (National University of Defense Technology,Changsha 410073) 2000, 20 (04):  .  Abstract ( 1675 )   An object oriented analysis method for liquid rocket engine system is stu died ,and the concepts and structure of three types of generalized components named as function component,checking component and system regulator are presented.The proces ses of dividing up and sequential calculation for the actual system are described,and the mathematical description of the method is given clearly.Applying the method to engine configuration study,the general methods for engine cycle power balance calculation and static characteristic analysis are established,and the methods are also achieved by object oriented programming.The engine configuration can be analyzed accurately and quickly with these programs.
 Design of Combinatorial Countering Algorithm for Selecting Positioning Constellations Liu Huijie Zhang Naitong (Harbin Institute of Technology Communication Research Center,Harbin 150001) 2000, 20 (04):  .  Abstract ( 1685 )   Data processing technologies are studied for satellite positioning system receiver,The optimal selection of positioning constellations is presented.That is a combinatorial optimization problem.Through further analysis,a m sequence based combinatorial countering algorithm is designed.Simulation and analysis is given for the algorithm result,Finally,the conclusion is provided.
 Effect of Spectral Bandwith in Infrared Earth Sensor on Design of Infrared Bandpass Filter for Satellite Huang Xingeng (Beijing Institute of Control Engineering,Beijing 100080) 2000, 20 (04):  .  Abstract ( 1700 )   Based on the film system design of infrared bandpass filter for satellite, analyzes the effects of different spectral bandwith in earth sensor on absorption and transmitted of Ge substrate and PbTe cladding material,and on equivalent index of refraction and reflectance loss of filter film system.The result of the design is given.Best spectral bandwith of earth sensor for satellite is proposed.
 Research on Buffer Performance Parameters of Docking Mechanism Influence on Docking Process Guan Yingzi Cui Naigang (Harbin Institute of Technology,Harbin 150001) 2000, 20 (04):  .  Abstract ( 1709 )   The nature of buffer system is very important factor to determine the dynamic properties of the success of docking operation in space.Due to lack of the experiment equipments,the dynamic simulation on computer is an effective method to test and verify the parameters or evaluate the performance of the buffer system designed.In this paper,for the androgynous and peripheral type docking mechanism with electromechanical buffer system,the influence of the buffer system on the docking process is studied in help of the dynamic simulation in detail.The conclusion provides basis of the engineering design of the buffer system.