Finite-time attitude control for flexible spacecraft with unknown bounded disturbance

Abstract

This paper studies finite-time attitude control for a flexible spacecraft with unknown bounded disturbances. Aiming at reducing vibrations excited by attitude manoeuvring, we develop a new manoeuvre path by combining path planning with the input shaping technique. Also, based on terminal sliding mode and the exponential reaching law, we propose a modified fast non-singular finite-time control law, which can achieve rapid finite-time convergence in the reaching phase as well as in the sliding phase. Furthermore, we design a weighted homogeneous extended state observer to estimate and thus to attenuate the unknown bounded disturbances in finite time. Finite-time stability of the overall system is analysed via Lyapunov technique, and simulation results demonstrate the effectiveness and robustness of the proposed control scheme.

Attitude Maneuvering and Vibration Reducing Control of Flexible Spacecraft Subject to Actuator Saturation and Misalignment

“…Path Planning. From 2and 3, it is known that attitude maneuvering would excite appendages' vibration [8], which is closely related to the attitude angular acceleration. A sudden change in attitude signal, especially in the form of step signal, may cause a serious appendages' vibration.…”

“…Relevant drawback of these control strategies is either the extra necessity to measure the modal variables or to treat the rigid-flexible coupling effect as an additional disturbance acting on a rigid structure. With regard to the latter situation, an extended state observer [7,8] is designed to estimate and thus to attenuate the total disturbance in finite time, including an external disturbance torque and the coupling effect. As a result, the prior knowledge of the total disturbance is not required.…”

Disturbance observer-based second order sliding mode attitude tracking control for flexible spacecraft

“…In [16] the ESO technique and the control Lyapunov function approach are merged to design an attitude controller under actuator saturation. Zhong et al [35] developed a robust ESO-based SMC scheme to control attitude tracking and vibration suppression of flexible spacecraft. These ESO-based SMC schemes provide better robustness than the common SMC.…”

Finite-Time Attitude Stabilization Adaptive Control for Spacecraft with Actuator Dynamics

“…In addition, a smooth projection scheme was proposed to prevent drifting of the parameter estimates. In [12], the finite-time attitude control for flexible spacecraft was addressed. A controller was proposed using the fast nonsingular terminal sliding mode manifold with a weighted homogeneous extended state observer estimating unknown disturbance.…”