Stability and control of an atmospheric tether with a lifting probe

This paper explores the stability and control of an atmospheric tether syst em that includes a lifting probe with a moveable attachment point. The dyna mics of the system with the tether modeled as a rigid rod are linearized ab out equilibria for circular equatorial orbits. Examination of the eigenvalu es of the linearized system shows that there is always at least one unstabl e mode that needs to be controlled. A linear control system that uses the a ttachment point motion and thrust at the orbiter as inputs is shown to be s uitable for the conditions considered. The system is also controllable with any single control input.