Understanding Agile-Maneuver Driving Strategies Using Coupled Longitudinal/Lateral Vehicle Dynamics

Agile maneuvers performed by professional racing car drivers have shown superior travel time and agility. These agile unstable yet safe maneuvers can be potentially used for active safety feature for high-speed obstacle avoidance or other emergency driving. Understanding the driving strategies during these agile maneuvers is however still not clear. In this paper, we first present coupled longitudinal/lateral vehicle dynamics and stability. Based on the stability analysis, we discuss agile maneuver driving strategies under which the vehicle is operated outside the stability region while still maintaining the safety. A new concept of safety boundary is used to quantitatively capture the safe region in the state space of vehicle dynamics. We use pendulum-turn agile maneuver experiments and CarSim simulations as an example to illustrate the analysis. We demonstrate that driving strategies are not unique to achieve high agile maneuvers such as pendulum-turn maneuvers.