Chad T. Zagorski

Optimal braking and steering control for active safety

The paper summarizes the development of an optimal braking and steering control for collision avoidance maneuver. The goal is to minimize the distance to the target vehicle ahead of the host vehicle subject to vehicle and environment constraints. Comparative study of standalone steering versus braking in a collision avoidance maneuver is given and results are discussed. The collision avoidance steering maneuver is effective only when the forward velocity is above a certain limit dictated by the surface friction coefficient and vehicle/tire characteristics. The algorithms were implemented in Simulink and verified in CarSim. The results indicate that there is an optimal braking and steering control resulting in minimal distance needed for collision avoidance maneuvers.

Path Planning for Collision Avoidance Maneuver

This paper summarizes the development of an optimal path planning algorithm for collision avoidance maneuver. The goal of the optimal path is to minimize distance to the target vehicle ahead of the host vehicle subject to vehicle and environment constraints. Such path constrained by allowable lateral (centripetal) acceleration and lateral acceleration rate (jerk). Two algorithms with and without lateral jerk limitation, are presented.The algorithms were implemented in Simulink and verified in CarSim. The results indicate that the lateral jerk limitation increases time-to-collision threshold and leads to a larger distance to the target required for emergency lane change. Collision avoidance path without lateral jerk limitation minimizes the distance to the target vehicle and is suitable for path tracking control in real-time application; however tracking such a path requires very aggressive control.Copyright