Abstract:

 With the continuum modeling method based on the energy equivalent principle, the configuration of the multi-rotary joints SPS is simplified to an equivalent flexible beam model. In the presence of the gravity gradient, the coupling dynamical model of the attitude motion and structural vibration is established. The improved method which combines the Runge-Kutta method with the Newmark method is proposed for the coupling equations of the attitude motion and structure vibration. The numerical efficiency is greatly improved compared with the classical Runge-Kutta method. It is used to obtain the dynamical responses under the different parameters. The relationship is derived that the order of magnitude of the structural vibration increases with the sixth order of magnitude of the structural size. The instability phenomenon which may be caused by the extreme oversize is found through the simulation results. The influence of the rotation and the gravity gradient on the frequency and the amplitude of the structural vibration is investigated. The increase of the period of the attitude motion due to the flexibility of the structure is discussed, which is more obvious in the lower orbit and the larger initial attitude angle.

Key words: Space solar power station, Continuum equivalent modeling, Flexible beam structure, Attitude Structure coupling, Gravity gradient