Path Planning and Motion Control in Evasive Steering Assist

Frontal collision is the leading cause of passenger vehicle occupant death in the recent years. Active safety systems like automatic emergency braking has been demonstrated to be able to mitigate frontal collision or to reduce collision impact. However, braking is not as effective as steering when host vehicle is at high speed, since it typically requires more minimum safety distance for braking than for steering to avoid a frontal collision. Evasive steering assist (ESA) is designed to improve driver’s steer maneuver in the case of a potential imminent front collision with another vehicle or VRU. If driver initiates a steering maneuver but that steering input is not enough to avoid the collision, then evasive steering assist will kick in to apply an additional steering in the direction of the driver’s input, to help driver complete the evasive steering maneuver stably and safely. This paper discusses our recent development effort in ESA, including architecture design, path planning, steering control, and experimental verification. A 5th order jerk-optimal path planner and an LQR controller for ESA are elaborated. Real vehicle tests are conducted in test track with an EuroNCAP-style balloon car as obstacle. The effectiveness of our ESA algorithm under different test cases are verified.