H-Infinity Observer for Vehicle Steering System with Uncertain Parameters and Actuator Fault

Hongwei Wang,Qianyu Wang,Haotian Zhang,Jie Han

doi:10.3390/act11020043

Abstract

In this paper, an actuator fault diagnosis and reconfiguration problem is discussed for an uncertain vehicle steering system with external disturbances. Aiming at the factors affecting the control performance, a fault reconstruction strategy based on H-infinity observer is designed to improve the vehicle stability under complex conditions when the actuator fails. Firstly, aiming at the uncertain part caused by the road condition transformation, a mathematical model of dual input and dual output four-wheel steering system is established. Secondly, an augmented system is constructed in which the augmented state vector consists of the original state and actuator faults. Thirdly, the H-infinity observer is designed, and the gain of the observer is obtained by the Lyapunov function and linear matrix inequality. Finally, the effectiveness of the proposed strategy is verified by MATLAB/Simulink and Carsim co-simulation.

Highlights

With the increase in the number of vehicles on the road, the frequency of traffic accidents is gradually increasing [1]
The steer-by-wire (SbW) system is an electronically controlled vehicle system and can greatly improve the dynamic performance of vehicle [2,3], but actuator fault often occurs in the vehicle steering system due to long period, high load and high strength, which affects the normal operation of equipment and even causes safety accidents
Research on the actuator fault diagnosis of vehicle steering systems is of great significance to reduce the probability of traffic accidents

Summary

Introduction

With the increase in the number of vehicles on the road, the frequency of traffic accidents is gradually increasing [1]. Most actuator fault diagnosis methods are model-based because of their high speed and load independence. A robust control algorithm based on output feedback is proposed for the vehicle steering control system with actuator fault and the uncertainties in the tire cornering stiffness [20]. Authors of [25] consider external interference and the uncertainty of tire sidetrack stiffness and propose an observation-based control strategy to improve the maneuverability and stability of four-wheel independent-drive electric vehicles with an active front-wheel steering system. In the Section an convenient actuator and fault diagnosis observer i of the control strategy, the research object of this paper was a simplified vehicle model, Section 4, the proposed H-infinity observer is simulated and verified. Robust H-infinite observer was designed based on the Lyapunov method and LMI technology, and theoretical proof was constructed

System

D TP α4 γ

Simulation

Fault Occurs at Different Times

Slippery

Conclusions