Research on Lateral-Longitudinal Coupling Trajectory Tracking Control Method for Bilateral Electric Drive Tracked Vehicle

To improve the trajectory tracking accuracy of a tracked vehicle with a bilateral electric drive power system, a lateral-longitudinal coupling trajectory tracking control method is proposed in this paper. Firstly, the longitudinal reference speed sequence is generated by an iterative algorithm with consideration of rollover and sideslip constraints. Based on the model predictive control (MPC) method, reference speed, kinematic model of the tracked vehicle, and dynamic constraints, a lateral-longitudinal coupling trajectory tracker is established to solve the motor speed control command on both sides. According to the ROS-VREP co-simulation test, the path tracking accuracy of the proposed control method is improved by 28.49% and 43.75% under the steering conditions of small curvature and large curvature, compared with the decoupling control method, respectively. In addition, the vehicle presents higher driving stability without sacrificing time cost. The algorithm is tested on the actual vehicle platform, and the results are compared with the simulation tests. It is observed that the accuracy is roughly the same, while the error is within an acceptable range.