Modeling and simulating the stratosail of stratopheric satellite

A stratosail has no engine thrust but has the traction by the tether, and the size and direction of the traction have close relationship with the spatial shape of the tether, the wind field and the relative position between the super-pressure helium balloon and the stratosail. This increases some new difficulty in modeling the stratosail. In so doing, the stratosail´ reliance on the local wind field to produce its control force is the major factor for consideration. This paper establishes the model for the coordinate system that describes the forces received by the stratosail in a stratospheric satellite and analyzes the actions of its gravity and aerodynamic force and those of the tension of the tether. It also calculates with simulation examples the attitude of the stratosail and the size and angle of tension of the tether under the moment-equilibrium condition, verifying that the model thus established is valid.