Fault-Tolerant Controller Design for Path Following of the Autonomous Vehicle Under the Faults in Braking Actuators

Abstract

This article proposes a fault-tolerant control (FTC) strategy for path following of autonomous vehicles considering faults in the braking actuator. Distinguished from other relevant research, a fault model is designed, and a synthetic fault factor is calculated for the electrohydraulic brake (EHB) system in the case of differential braking. By considering the synthetic fault factor as a time-varying parameter, robust gain-scheduling linear parameter-varying ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LPV</i> ) synthesis <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">H</i> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_\infty $ </tex-math></inline-formula> performance fault-tolerant controller (LPV/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{H}_\infty $ </tex-math></inline-formula> -FTC) is designed to ensure autonomous vehicle stability and safety. In order to deal with different types of braking actuator faults, a generalized fault model is built first. Then, in the case of differential braking, a fault model is proposed for the EHB system based on the generalized fault models, which makes for the analysis and design of the controller. After that, an <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LPV</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">H</i> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_\infty $ </tex-math></inline-formula> output feedback fault-tolerant controller and a braking allocation scheme are designed to ensure the autonomous vehicle’s stability and safety under the faults in braking actuators. Finally, the experiments in the HIL system are carried out to verify the effectiveness and real-time performance of the proposed control strategy, and the results show that the proposed control strategy can improve the vehicle’s stability and safety under a wide range of types of faults in the EHB system.

Topics & Concepts