Analysis and Experiments of an Electromagnetic Docking Mechanism for Repeated Docking and Separation of the CubeSats

With the background of on-orbit repetitive connection and separation of CubeSats, an electromagnetic docking mechanism for repeated docking and separation is proposed. A reusable electromagnetic docking scheme combining lead screw transmission with electromagnets is introduced. The electromagnetic force/torque model and the attitude model of the CubeSat are derived based on the relationship between force and magnetic flux density in a magnetic field. The coil layout and the polarity of magnetic poles are optimized and analyzed, four different layout configurations are proposed, and their mechanical characteristics are analyzed. A multi-body dynamics simulation analysis of the entire mechanism is conducted to evaluate the attitude correction capability of the electromagnetic attraction separation unit. A three-degrees-of-freedom capture and separation test of the electromagnetic attraction separation unit is carried out in a microgravity-simulated environment to investigate the characteristics of capture and separation under different position and attitude deviation conditions of the energized solenoids. The designed electromagnetic docking mechanism has an adaptive attitude adjustment and docking range of a 30° cone. It can achieve low-impact, high-tolerance, and reusable docking and separation.