Collision Avoidance with Transitional Drift Control

Enhancing driving safety is a continuing effort towards safer transportation in the automotive industry. It is generally accepted that one of the benefits brought about by increasing levels of automation in vehicles is increased safety. In this paper we propose an automated emergency maneuver controller for safely and stably operating the vehicle at its handling limit in emergency situations. This paper explores the possible scenarios where such an ability is critical to keep an autonomous vehicle safe in an emergency scenario, by implementing a mode switching control design that successfully enhances safety in a driving scenario that would have caused an accident had the vehicle been operated by traditional vehicle control algorithms. The proposed mode switching control design uses geometric and kinematic criteria to determine the mode of operation for a vehicle, and applies tailored optimal control in each mode to minimize the safety risk in a finite planning horizon. The proposed method outperforms two control baselines including a drift sustaining controller in simulation by having the additional flexibility in following a challenging direction-changing path at considerable speed.