Tethered Dynamics Explorer and Tethered Atmospheric Probe - A low-cost, low-risk tethered satellite program

Ground-based implementation and verification of control laws for tethered satellites

“…A mass of 22 g was placed on the end of the tether to produce a static tension in the tether, which is slightly larger than the static tension the actual system will experience when fully deployed. 2 In such a configuration, the equations of motion governing the pendu- lum system are analogous to those of the system model used by Rupp 4 and Baker et al, 5 if air damping is ignored. Using a Lagrangian formulation, the equations are…”

“…2 The classical family of Bode magnitude and phase curves depicted in any standard text on vibrations, dynarnic systems, or control theory illustrates this dependency. It is seen that the slope of the phase curve at the point (GJ W , -90 deg) varies over a wide range from the critically damped ({"= 1) to the undamped (f=0).…”

“…The generalized second-order system transfer function transforms to the frequency transfer function (1) (2) Received Nov. 2,1990; revision received Feb. 14, 1991; accepted for publication Feb. 25, 1991. Copyright © 1991 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.…”

“…Originally a free-flying tethered system released from a getaway special canister on the orbiter, 1 the system is now one experiment in the tether dynamics explorer (TDE) series launched by a Delta II. 2 The system consists of a Delta II second stage and subsatellite connected by a single tether. The subsatellite contains a motorized reel mechanism that will be the primary means of control actuation.…”

Modeling of a Tethered Testbed for a VTVL Vehicle

“…Several ideas to support and accelerate the GNC development using demonstrators have been conceived in the past, for example NASA's Morpheus lander [1,2] or the HOMER demonstrator of Airbus Defense and Space [3,4]. In these and other developments of space systems, a wide variety of tethered experimental setups has been created [1,2,[5][6][7][8].…”