The motion of the aerodynamic tether system includes two stages โ the deployment and the motion of the deployed system. The initial condition for the deployment model is that of a spacecraft with a rigidly connected second body in a circular orbit about the planet. The deployment process is based on the aerodynamic forces acting on bodies. After the separation of the rigid connection, further motions of the bodies are then controlled by the tether release mechanism which unreels the tether and controls the rate at which the tether is unreeled. The
motion of the system is described by the multi-point model, splitting the tether into a number of
parts and using the series of separations of material points from the spacecraft, thus forming a mathematical model of the system with distributed parameters. The aerodynamic forces acting on the tether are taken into consideration. This model makes it possible to calculate numerically elastic deformations and curvature of the tether and provides more accurate modelling if
compared with the two-point model
