Robust Learning-Based Gain-Scheduled Path Following Controller Design for Autonomous Ground Vehicles

In this paper, a robust gain-scheduled path following controller for automated vehicles based on learning methods is presented. Two major challenges are overcome:1) Varying longitudinal velocity, uncertain cornering stiffness, and unmodelled uncertainties make dynamic-model-based controller design work complex. 2) Driving scenario changes deteriorate path following controller performance. An effective learning method, online updating least squares-support vector machine (LS-SVM) model is adopted for vehicle path following system considering varying velocity and cornering stiffness in this paper. Then the updating LS-SVM model is transformed into linear-parameter-varying (LPV) model with disturbance. The robust <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$H_\infty$</tex-math></inline-formula> controller design method is novelly employed to design path following controller for updating LS-SVM model. By this method a gain-scheduled output-feedback controller is designed. To improve transient performance, the poles of closed-loop system are assigned to desired regions. Simulation results using a high-fidelity and full-car model from CarSim have verified the effectiveness of the proposed control strategy.