Dynamics of Variable-Length Tethered Formations near Libration Points

摘要

The dynamics of multitethered satellite formations near libration points are presented. The system consists of anparent satellite and subsatellites, connected together in a hub–spoke configuration via variable-length tethers. BasednonHill’s approximation, a new dynamical formulation for nonrotating or rotating tethered formations is developed.nThe equilibrium positions are determined, and linearized analysis is performed for the nonrotating system withnconstant-length tethers. Numerical simulations using the full nonlinear and time-varying motion equations arencarried out for the stationkeeping and reconfiguration stages. For nonrotating systems, the motion of the parentnatellite is less stable for larger initial equilibrium positions during stationkeeping, and the tether librations duringndeployment are more stable than those during retrieval. For rotating systems, the orbital amplitude, orbitalndirection, and mass ratio have some impact on the stability of the system, and the retrieval is more conducive tonkeeping the system in its planar configuration when compared with the deployment.