Propellant Sloshing Torque H∞ – based Observer Design for Enhanced Attitude Control

Adaptive Minimal Control Synthesis for Satellite Attitude Control in Presence of Propellant Sloshing and Flexible Appendices

“…5. In contrast with the previously investigated control solutions, [7] and [8], where the closedloop system resulted incapable of recovering from instability consequent to actuation torque saturation, starting at target angle θ c ≈ 10[deg]; obtained results, for the proposed adaptive control strategy, confirm that even for long lasting saturation of the wheel, system convergence is still guaranteed both for large step and square wave, omitted here, tracking signal. However, a larger overshoot, and longer settling time, impossible to counteract due to the actuation system limitations, characterize the time response leading to unacceptable performances, starting at θ c = 25[deg].…”

“…In this framework, while preliminary results on Low Earth Orbit (LEO) small-sized satellites were very promising, reaction wheels saturation and coupling dynamics with flexible appendices remain unresolved issues [7], [8]. These dynamics can no longer be neglected in the case of geostationary (GEO) or interplanetary mission satellites, which are typically equipped with significantly larger solar arrays structures and propellant tanks.…”

Cryogenic propellant management in space: open challenges and perspectives

“…However, both these linear models have good accuracy for small amplitude liquid sloshing and axisymmetric tanks 61 – 64 . The biggest drawback is that these models do not take into account the dependency of the sloshing phenomena by the velocity and acceleration of the spacecraft that provokes non-negligible inertial forces/torques on the liquid 65 . More advanced studies, including non-linearities, were conducted by several authors 52 , 58 , 59 , 66 – 71 .…”

“…Most of the equivalent mechanical models 52 , 72 – 74 present the difficulty to identify its constitutive parameters (e.g., liquid friction force and torque) by a semi-empirical approach. Pioneering work on the sloshing control are proposed by the following references: 65 , 75 – 77 .…”