ESA GNC Conference Papers Repository

Under the umbrella of the Clean Space Initiative, ESA has promoted activities in the area of Active Debris Removal (ADR). One of the main challenges driving the complexity of the rendezvous and capture of debris is its tumbling motion. Observations of several non-operational LEO satellites often show angular rates above 2 deg/s. It is highly desirable that kinetic energy dissipation devices damp the angular rates of debris in advance. Eddy currents in conductive structures only provide a very slow detumbling. A potentially faster solution proposed by ESA (patent pending Ref EP19182205) consists in short-circuiting the satellite Magnetic Torquers already on board LEO satellites. The tumbling motion of the satellite within the Earth magnetic field results in the induction of currents in the Magnetic Torquers coils, dissipating energy by Joule heating. The long-term dynamics evolution of non-controlled satellites in Low Earth Orbit is summarised. An analytical framework modelling the impact of the Gravity Gradient and Satellite residual dipole torques and short-circuited Magnetic Torquers currents is proposed. A set of driving parameters (debris inertias, altitude, spin axis orientation, and Magnetic Torquers characteristics) permits a rough estimation of detumbling durations. Precursor tests with short-circuited Magnetic Torquers performed by LusoSpace in 2019/2020 are presented. Preliminary analyses and simulations including the detrimental effect of Sun Radiation Pressure on tumbling Solar Arrays are presented, together with the identification of driving parameters and potential mitigation actions.