摘要
The electric sail is an innovative propellantless propulsion concept that gains continuous momentum from the solar wind. In this work, the electric sail's attitude dynamics is established from a multibody perspective. Firstly, the dynamics of a single charged tether is described by a dumbbell model. Comparisons with an elastic multipoint model show that the dumbbell model is simpler and accurate enough to describe the motion of tether when the spin rate meets a specific lower bound. Then, the electric sail's attitude dynamics model is established through Kane's method based on the dumbbell model of the tethers. Finally, a case study is performed for the electric sail. It is shown that a 4-kmradius electric sail with 12 tethers of which the voltage is 25 kV could provide the sailcraft with a characteristic acceleration of 0.1 mm/s(2). The results also indicate that the satellite bus's acceleration oscillates with the undiminished out-of-plane swing of the electric sail, in which the period and amplitude are in inverse proportional to the spin rate and its square, respectively. Besides, a dynamical equilibrium point for system's attitude exists when the electric sail is perpendicular to the solar wind. The presented work offers a basic referential model for the real-time feedback control problems of the electric sail's attitude.
- 出版日期2018-12
- 单位北京理工大学; 中国空间技术研究院