  Recently, the spinning tethered system is regarded as a typical and
fundamental space structure attracting great interest of the aerospace
engineers, and has been discussed primarily for specific space missions in past
decades, including on-orbit capture and propellantless orbit transfer etc. The
present work studies the dynamical behaviours of a fast spinning tethered
binary system under central gravitational field, and derives principles of the
basic laws of orbital maneuver. Considering the characteristics of coupled
librational and orbital motions, an averaging method is introduced to deal with
the slow-fast system equation, thus a definite equivalent model is derived. The
general orbit motion is completely determined analytically, including the orbit
geometry, periodicity, conversations and moving region etc. Since the
possibility of orbit control using tether reaction has been proved by previous
studies, special attention is paid to the transportation mode of angular
momentum and mechanical energy between the orbit and libration. The effect of
tether length change on the orbit shape is verified both in the averaged model
and original model. The results show the orbit angular momentum and mechanical
energy can be controlled independently, and the operating principles of tether
reactions are derived for special modification of orbit shape.
