Propulsive Capability of a Reel-In Tether with Safe Separation Between Payload and Orbiter.

摘要

This study investigates the use of a massless reel-in tether for propulsion of a payload following deployment from an orbiter. The distance between the payload and orbiter at closest passage is addressed. A literature review revealed several tether concepts, extensive tether research, and numerous mathematical models. However, previous work in the area of reel-in tethers is limited to propulsion feasibility. The reel-in tether is operated following optimum ejection of the payload from the orbiter using a free arc and subsequent full arc. The free arc of zero tether tension provides initial separation. Switching to a full arc of continuously-maximum tension at the optimum time accelerates and propels the payload until the mission is complete. Tether and winch capabilities are assumed to be satisfactory during the arcs. Families of trajectories are examined for a range of mission times and minimum final payload energy. Families for two ejection speeds provide comparison of propulsion capability, tether length, and minimum separation radius. Safe separation is achievable through variation of the mission duration and/or the ejection speed.