Attitude and Power Analysis of Two-Node Multitetheral Coulomb Structures

The tethered coulomb structure is a novel approach to generating a large deployable and reconfigurable, near-rigid space structure. This concept uses electrostatic forces to repel a three-dimensional formation of spacecraft nodes interconnected through fine low-mass tethers. The tethered coulomb structure rotational stiffness characteristics are quantified through numerical analysis of the tethered coulomb structure node attitudes. With a two-node configuration, the rejection of angular rotation disturbances up to 50 deg/mm is computed. The maximum absolute angular deflection is reduced as much as 75% by using a triple tether over a single tether. Furthermore, the triple-tether setup can provide full three-dimensional stiffness, even for a two-node system. Variations in tethered coulomb structure nodal parameters show that low inertia nodes with wide tether attachments significantly increase the rotational stiffness. With applications targeted for geosynchronous Earth orbit, results Show that the differential gravity gradient forces have minimal effect on relative nodal attitudes. In addition, representative geosynchronous Earth orbit plasma conditions are modeled to demonstrate that plasma partial shielding has minimal effect on structure inflation under coulomb forces. Charging a tethered coulomb structure to negative potentials is advantageous, in that only watt levels of power are required to maintain quasi-rigid formations.