Orbital Deployment of Very Long Tethered Structures

摘要

Among the candidate configurations for future Radio Astronomy Explorer (RAE) spacecraft is a tethered orbiting interferometer consisting of two end bodies joined by a flexible cable several kilometers long. The system is launched as a single payload, then extended and gravitationally stabilized with its long axis nominally aligned with the local vertical. This paper presents some results of an inquiry into the feasibility of such a scheme, parametrically examining two potentially attractive in-orbit deployment techniques. The tether may pay out at near-zero tension to a preselected intermediate length, with librating capture and a subsequent 'deadbeat' extension to remove the libration. With reel-back capability, payout under a controlled tension can proceed continuously to librationless capture at the intended final length. Boundary conditions are established, engineering problems are discussed, and possible applications to other missions are explored. It is concluded that practicable means of implementation can be developed with existing technology. (Author)