Adaptive Output Feedback Control of Steer-by-Wire Systems With Event-Triggered Communication

This article addresses the event-triggered output feedback control problem for steer-by-wire (SbW) systems with uncertain nonlinearity and time-varying disturbance. First, a new framework of event-triggered control systems is proposed to eliminate the jumping phenomenon of event-based control input, in which the tradeoff between saving communication resources and attenuating jumping phenomenon can be relaxed. Then, an adaptive fuzzy logic system (FLS) is developed to approximate the uncertain nonlinearity, and an adaptive FLS-based state observer is developed to estimate the augmented SbW system state, such that the unnecessary sensors can be removed. In light of the sliding mode control technique and FLS-based state observer, an adaptive event-triggered control is proposed for SbW systems, such that controller-area-network communication resources can be saved. Much significantly, the effect of observation error and event-triggered error can be counteracted by the dynamic gain technique. Furthermore, theoretical analysis based on Lyapunov stability theory is provided to verify both the observer error of state and the tracking error of the SbW system can converge to a neighborhood of the origin in finite time. Finally, simulations and experiments are given to evaluate the effectiveness and superiority of proposed methods.