Research On Robust Control Of Intelligent Vehicle Trajectory Tracking

Intelligent vehicle trajectory tracking control and trajectory planning is the key technology and research hotspot to realize safe automatic driving,which has attracted the attention of many scholars and researchers,but there are still some problems in related fields.As an important channel for communication between vehicle components,the network time delay in the vehicle control system will weaken the control performance of the controller and reduce the driving stability of the vehicle,which will lead to safety accidents in serious cases.In addition,intelligent vehicle trajectory tracking control usually adopts feedback control method,which fails to make full use of road curvature and expected vehicle speed information,resulting in limited trajectory tracking control accuracy.In order to solve the above problems,this paper studies the intelligent vehicle trajectory robust tracking control,network time-delay control and lane changing trajectory tracking control as follows:(1)The vehicle dynamics model and vehicle road error model are established.Based on Serret-Frenet coordinate system,the vehicle kinematics model and three degree of freedom vehicle dynamics model are established,and the system state space model is obtained simultaneously.In order to solve the linear matrix inequality,the TS fuzzy method is used to deal with the four time-varying parameters of vehicle yaw rate,road curvature,vehicle speed and reciprocal of vehicle speed in the state space model.In order to solve the problem of calculation interval expansion caused by the coupling of vehicle speed term and vehicle speed reciprocal term,a smaller calculation interval is designed based on geometric method,which reduces the number of fuzzy rules and reduces the conservatism and calculation of the system.(2)A trajectory tracking controller without and with network time-delay control is designed.In order to realize the tracking control of the desired trajectory,a state feedback trajectory tracking controller without network time delay is designed based on the robust H∞ control algorithm and trajectory tracking model.In order to reduce the disturbance caused by network time delay,a state feedback trajectory tracking controller with time delay control is designed.The simulation results show that the designed controller has good tracking control performance.In addition,the time-delay controller has strong anti-interference ability to time-delay,and still has good performance even in the case of time-delay.(3)A feedforward angle compensation controller is designed.In order to improve the accuracy of trajectory tracking control,the feedforward compensation angle is calculated based on the vehicle kinematics model.Taking the actual vehicle speed and tracking lateral error as inputs,a feedforward angle compensation control algorithm based on variable universe fuzzy is proposed to calculate the scale factor in the feedforward compensation angle,which improves the utilization of the universe interval.The simulation results show that the feedforward angle compensation controller improves the accuracy of vehicle trajectory tracking control.(4)The lane change trajectory tracking control algorithm is designed.In order to ensure that the vehicle has better tracking control performance in the case of lane change,the optimal lane change trajectory is generated based on the quintic polynomial.Through the trajectory tracking control method designed above,the lane change trajectory tracking is realized,and a good tracking effect is obtained.The quality of the lane change trajectory and the tracking control effect of the designed controller are further verified.