Adaptive finite-time prescribed performance attitude tracking control for reusable launch vehicle during reentry phase: An event-triggered case

Abstract

This paper is devoted to address the attitude tracking problem for reusable launch vehicle (RLV) with uncertain aerodynamic parameters, input saturation and limited transmission resources. Based on the framework of the backstepping technique, a novel event-triggered adaptive prescribed performance control protocol is presented. Firstly, an extended state observer is used to provide the estimation for the whole system uncertainties. Then, an event-triggered mechanism is applied to exactly determine when control signals should be updated, which successfully eliminates the unnecessary periodic/continuous sampling in time-triggered researches and creates less waste of transmission resources. To compensate the negative effects induced by the aperiodic updating of control signals in event-triggered mechanism, an appointed-time prescribed performance controller is devised. In this way, the stability and tracking performance for the attitude system of the RLV can be guaranteed simultaneously. Moreover, the detailed theoretical analysis confirms that Zeno-free triggering is completely guaranteed along with stability. Finally, extensive simulations are carried out to validate the effectiveness of the proposed control protocol.