Evaluation of E-sail parameters on central spacecraft attitude stability using a high-fidelity rigid–flexible coupling model

This study examines the impact of electric solar wind sail(E-sail)parameters on the attitude stability of E-sail’s central spacecraft by using a comprehensive rigid–flexible coupling dynamic model.In this model,the nodal position finite element method is used to model the elastic deformation of the tethers through interconnected two-node tensile elements.The attitude dynamics of the central spacecraft is described using a natural coordinate formulation.The rigid–flexible coupling between the central spacecraft and its flexible tethers is established using Lagrange multipliers.Our research reveals the significant influences of parameters such as tether numbers,tether’s electric potential,and solar wind velocity on attitude stability.Specifically,solar wind fluctuations and the distribution of electric potential on the main tethers considerably affect the attitude stability of the spacecraft.For consistent management,the angular velocities of the spacecraft must remain at target values.Moreover,the attitude stability of a spacecraft has a pronounced dependence on the geometrical configuration of the E-sail,with axisymmetric E-sails proving to be more stable.

Optimal orbit transfer of single-tether E-sail with inertially fixed spin axis

This study analyzes the optimal transfer trajectory of a spacecraft propelled by a spinstabilized electric solar wind sail(E-sail)with a single conducting tether and a spin axis with a fixed direction in an inertial(heliocentric)reference frame.The approach proposed in this study is useful for rapidly analyzing the optimal transfer trajectories of the current generation of small spacecraft designed to obtain in-situ evidence of the E-sail propulsion concept.In this context,starting with the recently proposed thrust model for a single-tether E-sail,this study discusses the optimal control law and performance in a typical two-dimensional interplanetary transfer by considering the(binary)state of the onboard electron emitter as the single control parameter.The resulting spacecraft heliocentric trajectory is a succession of Keplerian arcs alternated with propelled arcs,that is,the phases in which the electron emitter is switched on.In particular,numerical simulations demonstrated that a single-tether E-sail with an inertially fixed spin axis can perform a classical mission scenario as a circle-to-circle two-dimensional transfer by suitably varying a single control parameter.