Composite Event-Triggered Intermittent Attitude Control of Spacecraft
Jiakun Lei, T.H. Meng, Kun Wang, Weijia Wang, Shujian Sun
Abstract
This paper focuses on the spacecraft attitude control problem with intermittent actuator activation, considering the parameter uncertainty and external disturbance issue simultaneously. To address this problem, we propose a Composite Event-Trigger Mechanism (CETM), which consists of two state-dependent triggers governing the activation and deactivation of actuators. Subsequently, by introducing the cascaded decomposition of the Backstepping control philosophy, the designed CETM trigger mechanism is applied to the decomposed dynamical subsystem, providing a layered intermittent stabilization strategy called the Composite Event-Triggered Intermittent Control (CETIC). Moreover, the proposed CETIC framework is further extended to address exogenous perturbations by introducing the extended-state observer technique, and a Disturbance Observer-based Composite Event-Triggered Intermittent Controller (DO-CETIC) is then developed. Further, by analyzing the boundedness of the Lyapunov certificate on each inter-event time interval, a uniformly, strictly decreasing upper bound of the lumped system is then characterized, completing the proof of the system's ultimate boundedness. Finally, numerical simulation results are illustrated to demonstrate the effectiveness of the proposed control scheme.