THE INTEGRATED NAVIGATION EGUIPMENT FOR LOW-ORBIT SPACE VEHICLES EXPLORING THE EARTH SURFACE

摘要

The global navigation satellite systems (GLONASS created in Russia and GPS created in U.S.) quickly change the architecture of future space vehicles (SV) and space systems for other purposes. GPS/GLONASS navigation equipment is used by developers of space systems intended for both civil and military applications. At present, a number of U.S. organizations and agencies begins to develop and test the satellite navigation devices purposed especially for operation on space platforms. The U.S. Commission which estimated managerial/organizational issues of U.S. space activity in the interests of national security has made a conclusion on particular importance of space aids for functioning all national infrastructure (Commission's paper of January, 2001). It is proposed that the onboard control systems of modern low-orbit SV for Earth's remote sensing (SV ERS) would realize functions of autonomous navigation support allowing to provide users onboard SV with motion parameters. As regards the operation environment of SV ERS, a high dynamics of SV's motion around the center of mass takes place. It is caused by a necessity to change the SV's attitude when pointing an optical axis of sensing equipment to the appropriate objects at the Earth's surface. The requirements of quick-acting, when sensing one or the other of objects, define also a high dynamics of center-of-mass motion due to necessity to purposefully change flight orbital parameters. Accuracy and quick-acting, when obtaining motion parameters, set, first of all, characteristics of programs for SV's purpose-oriented functioning which are generated by the control system and, finally, the efficiency of remote sensing process realized by SV's.