Semiglobal Finite-Time Stabilization of Saturated Spacecraft Rendezvous System by Dynamic Event-Triggered and Self-Triggered Control

Abstract

This article proposes the dynamic event-triggered control (ETC) and self-triggered control (STC) to achieve the semiglobal finite-time stabilization (SGFTS) of spacecraft rendezvous system with input constraints. Based on the Clohessy–Wiltshire equation, a bounded dynamic ETC algorithm is first designed, where the time-varying control gain will approach to infinity at finite-time and only be scheduled on a specified time determined by an dynamic event-triggered mechanism. This algorithm can achieve the SGFTS of the closed-loop system and save the communication resources. Moreover, the corresponding dynamic STC that only uses the data information at the previously triggered time to precompute the next triggered time is designed. By exploring the properties of the parametric Lyapunov equation, a positive minimal interevent time (MIET) of the designed dynamic ETC and STC can be obtained, such that the Zeno phenomenon is avoided. In some cases, the MIET can totally avoid the relationship with the system itself and be designed as an arbitrarily large bounded constant. Finally, simulation results verify the effectiveness of the designed algorithms.