Collision Imminent Steering Using Nonlinear Model Predictive Control

Collision imminent steering is an automotive active safety feature designed to swerve and avoid an obstacle on the road if the vehicle detects a forward collision cannot be avoided by braking alone. A collision imminent steering system is formulated in this paper to generate an optimal control sequence that performs an aggressive lane change maneuver in the shortest distance possible in a highway driving environment. The algorithm uses nonlinear model predictive control that pushes the vehicle to its dynamic handling limits, which are established through limits on the tire slip angle. Additionally, the algorithm is developed to leverage active four wheel steering to improve the performance over traditional front only steering. Numerical results show a window exists for which the vehicle can change lanes safely, even at highway speed. A Pareto front is generated to quantify the trade-off between maximum allowable tire slip and safe steering distance.