Dynamics and energy analysis of continuous cislunar transfer system

To study the dynamics and energy of continuous cislunar transfer system, under the conditions of rigid rod presumption and overlooking the perturbations of the third-body gravitation, the oblateness of the Earth and the axial deformation, by using the Lagrange method, a three-dimensional rigid dynamic model of motorized momentum exchange tether (MMET) is built, which has been verified under numerical simulation, comparison and analysis. Studies show that the external torque has less influence on the orbit movement but has evident influence on those attitude parameters. Entry velocity condition and time period condition, which ensure that payload enters the cislunar transferring trajectory successfully, of MMET have been deduced theoretically. Furthermore, the time interval between two payloads transferring missions is solved. Under the given initial conditions, if the rotational angular velocity of MMET is 0.231 6 rad/s, when MMET rotates around its center of mass by 1 448.5 circles and MMET orbits Earth for 5 circles simultaneously, the payload can enter cislunar transfer trajectory successfully. The analysis of energy requirement, which is needed by MMET way or traditional impulse transfer way when transferring payloads from Earth to Moon, has been studied. It is illustrated that under the same conditions, the way of MMET needs less energy.