Trajectory tracking control method and system based on longitudinal and transverse coordination

Abstract

The invention discloses a trajectory tracking control method and system based on longitudinal and transverse coordination. The trajectory tracking control method comprises the steps of information perception, trajectory planning, control layer modeling and driving execution. According to information perception, traffic environment information and vehicle state information of the intelligent vehicle are collected in real time; according to path planning, an expected path is planned according to information perception data; according to control layer modeling, a longitudinal and transverse coordination strategy is established according to a preview principle, an expected longitudinal and transverse control instruction is processed and the expected longitudinal and transverse control instruction is converted into an executable control instruction physical value; and according to driving execution, an execution mechanism of the vehicle is executed according to the physical value of the control instruction to realize the overall control of the vehicle. According to the method, a simple two-wheel dynamic model and kinematics are adopted for modeling the unmanned vehicle, feedback and feedforward steering control is designed through a backstepping method principle according to road information and vehicle motion characteristics, and compared with traditional PID control and nonlinearmodel prediction control, the accuracy and the real-time performance are improved.

Description

technical field [0001] The invention relates to the field of intelligent vehicle control, in particular to a trajectory tracking control method and system based on vertical and horizontal coordination. Background technique [0002] The control technology of unmanned vehicles is divided into lateral control and longitudinal control, so the automatic trajectory tracking technology needs to realize the fusion control of the two at the same time. At present, trajectory tracking control only considers the lateral control of the vehicle at a constant speed or a certain speed, and the longitudinal control based on the target speed. This type of technology can only ensure trajectory tracking in simple road conditions such as expressways and small curvature roads. . Under normal road conditions, the driver will properly adjust the speed of the vehicle according to the curvature of the road to ensure the stability of the vehicle. At this time, the steering control of the vehicle also...

AI Technical Summary

Problems solved by technology

The vehicle trajectory tracking longitudinal and lateral control algorithm designed based on motion geometry can guarantee a certain control performance on low-speed and low-curvature roads, and has the advantages of simple controller design and easy adjustment of control parameters. , because the change of the vehicle's own dynamic characteristics will reduce the performance of trajectory tracking control, it cannot meet the requirements of automatic driving control on high-speed and large-curvature roads

Using a complex vehicle dynamics model to couple longitudinal and lateral control, considering that the dynamic elements of the vehicle are relatively rich, the model is relatively accurate, but its complexity is not conducive to the design of control algorithms. In addition, the above two algorithms do not fully consider the influence of factors other than the vehicle (such as road factors, environmental factors, etc.) Requirements for vertical and horizontal control of human driving trajectory tracking

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