Adaptive Finite-Time Fault-Tolerant Control for Half-Vehicle Active Suspension Systems with Output Constraints and Random Actuator Failures

Jie Lan,Tongyu Xu,Rui Wang

doi:10.1155/2021/5964034

Abstract

The problem of adaptive finite-time fault-tolerant control (FTC) and output constraints for a class of uncertain nonlinear half-vehicle active suspension systems (ASSs) are investigated in this work. Markovian variables are used to denote in terms of different random actuators failures. In adaptive backstepping design procedure, barrier Lyapunov functions (BLFs) are adopted to constrain vertical motion and pitch motion to suppress the vibrations. Unknown functions and coefficients are approximated by the neural network (NN). Assisted by the stochastic practical finite-time theory and FTC theory, the proposed controller can ensure systems achieve stability in a finite time. Meanwhile, displacement and pitch angle in systems would not violate their maximum values, which imply both ride comfort and safety have been enhanced. In addition, all the signals in the closed-loop systems can be guaranteed to be semiglobal finite-time stable in probability (SGFSP). The simulation results illustrate the validity of the established scheme.

Highlights

With the development of modern industrial automation, vehicles play a more and more important role in people’s production and life
Many progresses have been made for uncertain nonlinear active suspension systems (ASSs), and a few studies were on the constraint of half-vehicle models
Motivated by the above observations and existing research results, this study proposes an adaptive neural network (NN) finite-time fault-tolerant control (FTC) scheme for uncertain nonlinear half-vehicle ASSs with output constraints. e three main advantages of the proposed scheme can be listed as follows: (1) Compared with existing adaptive FTC studies, the problem for half ASSs subject to infinite stochastic actuator failures and the states of multiactuators modeled by different Markovian processes has not received enough attention

Summary

Introduction

With the development of modern industrial automation, vehicles play a more and more important role in people’s production and life. Motivated by the above observations and existing research results, this study proposes an adaptive NN finite-time FTC scheme for uncertain nonlinear half-vehicle ASSs with output constraints. (2) In comparison with existing constraints, it is asymmetry, which can restrain different outputs of displace and pitch angle more reasonable and reduce the vibration in uncertain nonlinear half ASSs. the finite-time FTC control strategy can enable the practical control systems to realize the transient system stability. (3) In comparison with existing adaptive finite-time control, it considers a class of uncertain nonlinear half-ASSs subject to stochastic actuator failures. It should dispose random terms which makes the existing stability criteria in [53,54,55] are invalid.

System Description and Preliminaries

Simulation Example

Conclusions