Orbital radius keeping of floating partial space elevator in cargo transposition

A floating partial space elevator (PSE) is a PSE with a floating main satellite. This work aims to keep the orbital radius of the main satellite of a floating PSE in cargo transposition without the use of thrusts. A six-degree-of-freedom two-piece dumbbell model was built to analyze the dynamics of a floating PSE. By adjusting the climber’s moving speed and rolling of the end body, the main satellite’s orbital radius can be kept. A novel control strategy using a proportional shrinking horizon model predictive control law containing a self-stability modified law is proposed to stabilize both the orbital and libration states to regulate the speed of only the climber. Simulation results validated the proposed control strategy. The system provides a successful approach to the desired equilibrium by the end of the transposition.