Four-wheel independent steering(4 WIS) system and direct yaw moment control(DYC) have an important influence on vehicle lateral stability. However, DYC has a great effect on the longitudinal velocity, and the capabili...Four-wheel independent steering(4 WIS) system and direct yaw moment control(DYC) have an important influence on vehicle lateral stability. However, DYC has a great effect on the longitudinal velocity, and the capability of 4 WIS is limited to stability.To decrease the influence on the longitudinal velocity and improve the stability of electrical vehicles, a chassis controller integrated with a 4 WIS system and a DYC system with model predictive control(MPC) is designed. The framework consists of an unscented Kalman filter(UKF) observer and an MPC that contains three blocks: supervisor blocks, upper blocks and lower blocks. First, the sideslip angle, longitudinal velocity and lateral tire forces are estimated by the UKF observer;second, a bicycle model is utilized in the supervisor to calculate the desired values;third, the upper blocks are designed with the MPC to optimize the target steering angles and longitudinal tire forces under the constraints of subsystems;to facilitate the design of the MPC, a nonlinear tire is simplified based on the Taylor expansion method;finally, the target steering angles and longitudinal tire forces are achieved by the lower blocks. The integrated controller is simulated on the co-simulation platform of MATLAB-Carsim. The results show that the proposed integrated controller has less impact on longitudinal velocity and could effectively improve vehicle stability.展开更多
基金supported by the Natural Science Foundation Project of Chongqing(Grant No.cstc2018jcyjAX0077)the Open Fund of Key Laboratory of Advanced Manufacturing Technology for Automobile Parts,Ministry of Education(Grant No.2018KLMT06)the Graduate Research and Innovation Foundation of Chongqing,China(Grant No.CYB18059)
文摘Four-wheel independent steering(4 WIS) system and direct yaw moment control(DYC) have an important influence on vehicle lateral stability. However, DYC has a great effect on the longitudinal velocity, and the capability of 4 WIS is limited to stability.To decrease the influence on the longitudinal velocity and improve the stability of electrical vehicles, a chassis controller integrated with a 4 WIS system and a DYC system with model predictive control(MPC) is designed. The framework consists of an unscented Kalman filter(UKF) observer and an MPC that contains three blocks: supervisor blocks, upper blocks and lower blocks. First, the sideslip angle, longitudinal velocity and lateral tire forces are estimated by the UKF observer;second, a bicycle model is utilized in the supervisor to calculate the desired values;third, the upper blocks are designed with the MPC to optimize the target steering angles and longitudinal tire forces under the constraints of subsystems;to facilitate the design of the MPC, a nonlinear tire is simplified based on the Taylor expansion method;finally, the target steering angles and longitudinal tire forces are achieved by the lower blocks. The integrated controller is simulated on the co-simulation platform of MATLAB-Carsim. The results show that the proposed integrated controller has less impact on longitudinal velocity and could effectively improve vehicle stability.