Orbital maneuver for a rotating tethered system via tidal forces

Rotating tethered systems are regarded as fundamental space structures, attracting great interest among aerospace engineers, and have been discussed primarily for specific space missions including on-orbit capture and propellantless orbital transfer. The present work studies the dynamical behavior of a rapidly rotating tethered binary system under a central gravitational field and derives basic principles of orbital maneuvers. An averaging method is introduced to address the slow-fast system equation resulting from the characteristics of the coupled librational and orbital motions, and an equivalent model is derived. The general orbital motion is completely determined analytically, including the orbit geometry, the periodicity, the conservations, and the range of motion. Because the possibility of orbit control using tether reaction has been proved by previous studies, special attention is given to the transportation mode of angular momentum and mechanical energy between the orbit and the libration. The effect of tether length on the orbit is verified both in the averaged model and the original model. The results show that the orbital angular momentum and the mechanical energy can be controlled independently. Finally, the operating principles of tether reactions are derived for a special modification of the orbit.