Study on the stability of Tethered Satellite System

Tethered Satellite System has turned into a reality from theory, and has become a new research focus in the field of space science. However, the system's stability will directly affect the success of the mission. In this paper, the systems stability is deeply studied. First, the system's equilibrium conditions are derived according to the systems dynamics model, and the maximum extent that these conditions can be reached is determined. Second, the stability of the system equilibrium state is analyzed by utilizing Taylor expansion formula and stability criterion, and the required conditions that the tether parameters should be satisfied during a stable equilibrium state are also deduced. Finally, based on the stability of studied above, a range-rate control algorithm is developed to achieve the stable control of tethers deploying, keeping, and retrieving. Simulation results verify the validity of these conclusions, which provide a good reference for future experiments of Tethered Satellite System.