|Integrated Path Tracking Control of Steering and Differential Braking Based on Tire Force Distribution
Guodong Wang, Li Liu, Yu Meng*, Qing Gu, and Guoxing Bai
International Journal of Control, Automation, and Systems, vol. 20, no. 2, pp.536-550, 2022
Abstract : "The integrated path tracking control of steering and differential braking can significantly improve the tracking performance of autonomous vehicles in collision avoidance in the limit conditions. However, the distribution of steering and braking control rights has not received sufficient attention in the existing control method. The distribution strategy is relatively simple and lacks theoretical support. Therefore, aiming at the problem of the distribution of steering and braking control rights in the integrated path tracking control, a tire force distribution rule is proposed in this study, and a path tracking control method based on holistic model predictive control (MPC) is designed. To describe the coupling and strong nonlinearity of tire dynamics, a UniTire tire model with combined slip conditions is established in the controller model. Furthermore, the nonlinear controller model is linearized by Taylor expansion and a linear time-varying MPC controller is designed to improve the real-time performance of the system. Finally, the effectiveness of the proposed method is verified via the co-simulation tests of CarSim and Simulink. The simulation tests at the different speeds and road friction coefficients demonstrate the superiority of the proposed method in path tracking performance, lateral stability, and traffic efficiency.
Autonomous vehicles, differential braking, model predictive control, path tracking control, tire force distribution.