Hybrid controller approach for an autonomous ground vehicle path tracking problem

Abstract

This paper proposes a geometric model based lateral control system for a ground vehicle. Lateral control algorithm takes the advantages of two different path tracking methods at different path geometries. Two of the well-known geometric path tracking methods, namely Pure-Pursuit method and Stanley method, are combined with a simple and easy to implement approach. Pure-Pursuit method is very good at low speeds. However, as speed increases cutting corner behavior occurs and vehicle tends to converge to path relatively slow. In contrast, Stanley method convergence to the road is very fast and there is no cutting corner behavior. However since there is no look ahead behavior in Stanley method, it tends to overshoot from the desired path for sharp turns. In this work we propose a hybrid method to improve convergence to the path, prevent cutting corner and overshoot from the desired path.