Predictive Force-Centric Emergency Collision Avoidance

A controller for critical vehicle maneuvering is proposed that avoids obstacles and keeps the vehicle on the road while achieving heavy braking. It operates at the limit of friction and is structured in two main steps: a motion-planning step based on receding-horizon planning to obtain acceleration-vector references, and a low-level controller for following these acceleration references and transforming them into actuator commands. The controller is evaluated in a number of challenging scenarios and results in a well behaved vehicle with respect to, e.g., the steering angle, the body slip, and the path. It is also demonstrated that the controller successfully balances braking and avoidance such that it really takes advantage of the braking possibilities. Specifically, for a moving obstacle, it makes use of a widening gap to perform more braking, which is a clear advantage of the online replanning capability if the obstacle should be a moving human or animal. Finally, real-time capabilities are demonstrated. In conclusion, the controller performs well, both from a functional perspective and from a real-time perspective.

[1]  Mathias R Lidberg,et al.  On optimal recovery from terminal understeer , 2014 .

[2]  Zvi Shiller,et al.  Emergency Lane-Change Maneuvers of Autonomous Vehicles , 1998 .

[3]  Anil V. Rao,et al.  Faster, Higher, and Greener: Vehicular Optimal Control , 2015, IEEE Control Systems.

[4]  Lars Nielsen,et al.  Using Crash Databases to Predict Effectiveness of New Autonomous Vehicle Maneuvers for Lane-Departure Injury Reduction , 2021, IEEE Transactions on Intelligent Transportation Systems.

[5]  Lars Nielsen,et al.  Yaw-Moment Control At-the-Limit of Friction Using Individual Front-Wheel Steering and Four-Wheel Braking , 2019 .

[6]  Martin Törngren,et al.  Adaptive Trajectory Planning and optimization at Limits of Handling , 2019, 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS).

[7]  J. Christian Gerdes,et al.  Design of a feedback-feedforward steering controller for accurate path tracking and stability at the limits of handling , 2015 .

[8]  J. Christian Gerdes,et al.  A synthetic input approach to slip angle based steering control for autonomous vehicles , 2017, 2017 American Control Conference (ACC).

[9]  Lars Nielsen,et al.  Models and methodology for optimal trajectory generation in safety-critical road–vehicle manoeuvres , 2014 .

[10]  Yangyan Gao,et al.  Modified hamiltonian algorithm for optimal lane change with application to collision avoidance , 2015 .

[11]  Moritz Diehl,et al.  CasADi: a software framework for nonlinear optimization and optimal control , 2018, Mathematical Programming Computation.

[12]  Taxonomy and definitions for terms related to driving automation systems for on-road motor vehicles , 2022 .

[13]  Derong Yang,et al.  Optimal motion control for collision avoidance at Left Turn Across Path/Opposite Direction intersection scenarios using electric propulsion , 2018, Vehicle System Dynamics.

[14]  Yangyan Gao,et al.  Optimal control of brakes and steering for autonomous collision avoidance using modified Hamiltonian algorithm , 2019, Vehicle System Dynamics.

[15]  Hans B. Pacejka,et al.  Tire and Vehicle Dynamics , 1982 .

[16]  A. Kullgren,et al.  Injury risk functions in frontal impacts using data from crash pulse recorders. , 2012, Annals of advances in automotive medicine. Association for the Advancement of Automotive Medicine. Annual Scientific Conference.

[17]  Lorenz T. Biegler,et al.  On the implementation of an interior-point filter line-search algorithm for large-scale nonlinear programming , 2006, Math. Program..

[18]  H. Bock,et al.  A Multiple Shooting Algorithm for Direct Solution of Optimal Control Problems , 1984 .

[19]  Francesco Borrelli,et al.  Predictive Control of Autonomous Ground Vehicles With Obstacle Avoidance on Slippery Roads , 2010 .

[20]  Nabil Aouf,et al.  A Comparison of Trajectory Planning and Control Frameworks for Cooperative Autonomous Driving , 2021 .

[21]  Lino Guzzella,et al.  Optimal emergency maneuvers on highways for passenger vehicles with two- and four-wheel active steering , 2010, Proceedings of the 2010 American Control Conference.

[22]  E. Velenis,et al.  Minimum Time vs Maximum Exit Velocity Path Optimization During Cornering , 2005, Proceedings of the IEEE International Symposium on Industrial Electronics, 2005. ISIE 2005..

[23]  Derong Yang,et al.  Closed-loop Controller for Post-Impact Vehicle Dynamics Using Individual Wheel Braking and Front Axle Steering , 2012 .

[24]  Matthew Brown,et al.  Coordinating Tire Forces to Avoid Obstacles Using Nonlinear Model Predictive Control , 2020, IEEE Transactions on Intelligent Vehicles.

[25]  J. Christian Gerdes,et al.  From the Racetrack to the Road: Real-Time Trajectory Replanning for Autonomous Driving , 2019, IEEE Transactions on Intelligent Vehicles.

[26]  Huei Peng,et al.  Vehicle dynamics applications of optimal control theory , 2011 .

[27]  Jo Yung Wong,et al.  Theory of ground vehicles , 1978 .