Study On State Estimation And Lateral And Longitudinal Control For The Intelligent Electric Vehicle

As an significant part of the intelligent transportation system,the intelligent electric vehicle is an integrated multidisciplinary technology.The development of the intelligent electric vehicle will substantially improve the traffic efficiency and safety of the road system.Motion control is an important part of the intelligent vehicle research and the basis for other related links.Therefore,this paper focuses on the following aspects of the intelligent electric vehicle driven by in-wheel motor:(1)Establish a dynamic model of the intelligent electric vehicle driven by in-wheel motor.In order to accurately estimate driving state parameters of the vehicle,a seven-degree-of-freedom vehicle model is bulit,including vehicle longitudinal,lateral,yaw,and four-wheel rotation movements.It also contains the related sub models of the tire model and the motor model.Moreover,the vehicle model is verified by CarSim vehicle dynamics software.(2)Research on estimation of driving status of intelligent electric vehicles.Accurate and real-time acquisition of the driving state information of the vehicle is the premise of realizing longitudinal and lateral control of the intelligent electric vehicle.According to the advantages and disadvantages of traditional and improved Kalman filtering,an adaptive unscented Kalman filter algorithm(AUKF)that considers unknown system noise is designed.What's more,the algorithm is verified by simulation under the condition of sine and double shift lines respectively.(3)Research on longitudinal and lateral control of the intelligent electric vehicle.Firstly,the frame of the intelligent electric vehicle longitudinal and lateral control system was built.The lateral PD closed-loop control method is used to analyze the characteristics of the lateral system,and the preview distance is set based on fuzzy control.Then the lateral controller,which is composed of feedforward control and fuzzy feedback control,and the longitudinal controller based on sliding mode control are established.Finally,the control algorithm is verified under the condition of lane changing and lane keeping and tracking.(4)Establish a platform of the intelligent electric vehicle driving.In order to verify the effectiveness and robustness of the intelligent vehicle automatic driving system,an automatic driving test platform is built based on hardware in the loop technology.Considering the influence of human driving operation on the effect of automatic driving controller,the longitudinal and lateral control of the intelligent electric vehicle is verified.