ESO-based saturated deployment control of tethered satellite system with finite-time tracking performance guarantees

This paper investigates a novel finite-time saturated deployment control approach for the tethered satellite system in the presence of uncertain dynamics and space perturbations, as well as state constraints. First, an integral Lyapunov function is constructed to remove the hard state constraints characterized by a finite-time convergent performance function. Then, a backstepping finite-time deployment controller is devised via using an extended state observer (ESO) to approach the unknown dynamics, perturbations and saturation deviation. Compared with the existing finite-time control methods, the prominent advantage of the proposed one is that the finite-time saturated deployment control is achieved without violating the state constraints and using fractional state feedback. Finally, an illustrative example is organized to validate the effectiveness of the proposed approach.