Swing principle for deployment of a tether-assisted return mission of a re-entry capsule

Dynamics and control of a tether-assisted return mission of a re-entry capsule are considered. Efficiency of the braking process of the capsule depends on a deflection angle of the tether from a local vertical before separating the capsule from the tether. The aim is of this paper to find a tether length control law that allows to increase the deflection angle of the tether from the local vertical. The control law is based on a principle of a swing. This control law may be applied to the final phase to two possible options to perform a tether-assisted deorbit maneuver: static and dynamic release. An approximate analytical solution for the deflection angle from the local vertical is obtained for the control law. The numerical simulations have shown that the application of the control law allows a reduction in the required tether length of a tether-assisted deorbit maneuver. The proposed control law can be applied to develop new space tethered systems.