Lateral and Longitudinal Coordinated Control of Intelligent Vehicle Based on High-Precision Dynamics Model under High-Speed Limit Condition

This study focuses on improving the trajectory
tracking control for intelligent vehicles in high-speed and large
curvature limit conditions. To this end, a high-precision fivedegree-of-freedom (5-DOF) dynamics model (HPM) that incorporates suspension characteristics is introduced. Furthermore, a
coordinated lateral and longitudinal control system is developed.
The lateral model predictive control (MPC) involves two crucial
stages: initially, a desired trajectory with associated speed data
is generated based on path curvature. Subsequently, using the
high-precision 5-DOF dynamics model, an objective function
is formulated to minimize the difference between the vehicle’s
current state and the desired state. This process determines the
optimal front wheel steering angle, taking into account vehicle
positional constraints and steering limitations. Additionally, a
double proportional–integral–derivative (PID) controller for longitudinal control adjusts the throttle and brake pressure based
on real-time position and speed data, ensuring integrated control
over both lateral and longitudinal movements. The effectiveness
of this approach is confirmed through real vehicle testing and
simulation. Results show that the high-precision 5-DOF dynamics
model markedly enhances the accuracy of vehicle response modeling, and the coordinated control system successfully executes
precise trajectory tracking. In extreme scenarios of high-speed
and large curvature, the enhanced model substantially improves
trajectory accuracy and driving stability, thus promoting safe
vehicle operation.