Two-dimensional dynamics of a new configuration of continuous cislunar payloads transfer system

Based on the space tether, the concept of a motorized momentum exchange tether (MMET) using the momentum exchange principle has been proposed for many years. In this paper, a new symmetric configuration of MMET, referred to as HEX-MMET, is proposed. HEX-MMET has some unique advantages, such as higher payload transfer efficiency and shorter orbit reboost period compared to the MMET. In order to study the dynamic characteristic of HEX-MMET, using traditional Lagrange methods, a two-dimensional (2D) dynamic model of HEX-MMET is presented. Then, the numerical solutions based on MATLAB were implemented. The simulation results show that external torque has little evident influence on the orbital parameters, such as the radius of HEX-MMET's center-of-mass (COM) and the true anomaly; however, there is an apparent effect on the attitude parameters, such as the angle between the line of two payloads and the line of local gravity gradient. Furthermore, the gravity gradient torque also effects the attitude of HEX-MMET periodically.