Research On Attitude Dynamics Of Satellite In Electrodynamic Tethered Satellite Deorbiting And Attitude Determination Validation Based On MEMS Inertial Navigation Devices

In recent years,research on tethered satellite system becomes one of the hotspots in aerospace research.The research scope covers from physical field modeling,dynamic features analysis to control law design with lots of researches implemented.Meanwhile,space agencies of many countries have launched tethered satellite systems into space.One main branch of tethered satellite systems research is the electrodynamic tethered satellite system.The electrodynamic tether interacts with the geomagnetic field,affected by electrodynamic force with the opposite direction of motion,thus making the whole system descend gradually.In most of previous research on tethered satellite system,researchers focus on the dynamics of tether,and treat satellites as mass points without considering the influence of satellite attitude dynamics on the whole system.In contrast with previous research,we mainly focus on the attitude of satellite in electrodynamic tethered system deorbiting process.On one hand,by modeling the kinetic and dynamic equations of satellite,we implement numerical simulation.On the other hand,we emphasize the importance of attitude determination in tethered satellite system.Based on the research on error characteristics of MEMS inertial measurement devices,we implement a preliminary validation of measuring attitude of satellite in electrodynamic deorbiting processing MEMS INS/GPS.So researches are implemented on satellite attitude in tethered satellite system in both dynamic and geodetic ways,thus paving way for optimizing the performances of tethered satellite system and expanding its applications.The first innovation point of this thesis is that we mainly focus on the attitude dynamics of satellite in tethered satellite system.Based on the assumption that the tether is a rigid rod and the mass assumption of satellite is homogeneous,we analyze the attitude dynamics of satellite in electrodynamic tethered satellite system deorbiting process.In addition,the significance of research on satellite attitude control in electrodynamic tethered satellite system is demonstrated.In addition,the thesis sheds light on attitude measurement based on multi-sensor technology.Usage of MEMS INS/GPS integrated navigation on satellite position,velocity and attitude determination is put forward in this thesis.And research is implemented,focusing on error characteristics of MEMS INS sensors in both experimental and theoretical ways.Besides,validation simulation is demonstrated in which MEMS INS/GPS integrated navigation is used for attitude measurement in the dynamic process of eletrodynamic tethered satellite system deorbiting process.