Handling Stability Advancement With 4WS and DYC Coordinated Control: A Gain-Scheduled Robust Control Approach

Abstract

This paper focuses on the stability control algorithm for four-wheel independent steering (4WIS) and four-wheel independent drive (4WID) electric vehicle (EV) with the coordinated control of four-wheel steering (4WS) and direct yaw-moment control (DYC) techniques. In order to design an adaptive gain-scheduled robust controller for stability control, linear parameter-varying (LPV) system and H∞ optimal control theory are applied. The polytopic model is proposed to build the LPV system for 4WIS-4WID EV. Taking structured uncertainties and sensor noise into consideration, gain-scheduled robust controller is designed and worked out using linear matrix inequality (LMI). To verify the performance of the adaptive gain-scheduled robust controller, fishhook maneuver and sinusoidal steering maneuver are carried out based on hardware-in-the-loop (HIL) tests. Test results indicate that the adaptive gain-scheduled robust controller can improve vehicle s handling stability especially in extreme conditions. Meanwhile, the designed controller shows strong robustness to suppress system parametric perturbation.