CHARACTERISTICS OF COUPLED ORBITAL-ATTITUDE DYNAMICS OF FLEXIBLE ELECTRIC SOLAR WIND SAIL

This paper studies the dynamics of a tethered system with a moving climber in circular orbits in the framework of arbitrary Lagrangian-Euler (ALE) finite element method. The tethered space system is modeled by the nodal position finite element method, and the climber is implemented by positioning it at a moving node on the one-dimension medium, which is realized by variable-length element at either side of the moving node. The moving of climber is described by the increasing of the length on one side of the one-dimensional medium and a corresponding decreasing of the other side. The governing equations for the coupled system are derived in terms of D'Alembert's principle and the constraint equations are formulated in the standard form of differential algebraic equations of multibody systems. The technology of eliminating and adding of node is implemented to describe the climber moving along the flexible tether system. The dynamic response of the system when the moving climber moves along the tether connecting the two satellites is computed and analyzed.