Prospects of a Hybrid Magnetic/Electrostatic Sample Container Retriever

Martian sample return missions continue to be investigated to improve the understanding of planets. However, rendezvous and docking in deep space requires autonomous navigation and control capabilities. A deep-space satellite cannot be controlled by an Earth-based ground station in real time. As a solution of this deep-space docking challenge, the prospects of a sample container retriever using an electrostatic force and a flux pinning force are discussed in this paper. The proposed method uses the electrostatic interaction to retrieve an orbit sample (OS) container launched from a planet by a small rocket. The cylindrical OS studied in this research has three permanent magnets. To perform rendezvous and docking with the OS safely, a Martian sample return orbiter controls the angular velocity and attitude of the OS using electrostatic control when the sample is multiple meters away. When it is less than 1 m away, it is tugged to the orbiter and docked safely using the flux pinning effect. The feasibility of the proposed retrieval system is discussed from the aspects of the required electrical energy and the local space weather Debye length. To detumble the motion of the OS, a nonlinear controller is designed using a Lyapunov function as well as the Mukherjee and Chen theorem. The numerical performance simulations illustrate the feasibility and prospects of this method.