Research On State Parameter Estimation Of Vehicle Stability Control System

The Electronic Stability Control system is a computer technology that improves the vehicle's stability by detecting and reduces loss of traction.It determines the vehicle stability state by detecting the vehicle slip angle and yaw rate.When vehicle is in a state of instability or impending instability,it brakes the wheels to ensure the stability of the vehicle.The estimation of vehicle state parameters is the premise and basis for the work of vehicle stability control system,and it belongs to the key technology of vehicle stability control system.ESC has achieved mass production in foreign countries,and China is still in the primary stage of research and development.Therefore the study of the ESC system and estimation of state parameters has a positive impact on improving the technical strength of China's ESC system and the development of related industries.This paper analyzes the control effect and sensing configuration of the vehicle stability control system.Through the current two-degree-of-freedom model,the ideal yaw rate curve of the vehicle at various speeds is deduced,and the ?-theory is used to illustrate the stability of the vehicle.The relationship between the ideal maximum vehicle slip angle and speed was influenced and derived,and how the slip affects the tire force was discussed based on the Kamm circle theory.An overall framework for estimating the state parameters of ESC was built.The longitudinal velocity was estimated by steady Kalman filter,the tire force was estimated by the HSRI model,the lateral velocity was estimated by the extended Kalman filter,and the vehicle slip angle,the tire adhesion coefficient and slip were calculated by the estimated parameters.Based on the deduced mathematical model,a simulation model was built in Simulink,and a simulation test environment was set up in CarSim according to ISO-3888's high and low adhesion coefficient double lane change conditions.The simulation results show that the proposed ESC estimation method can meet the accuracy and real-time needs under simulation conditions.The HIL bench and vehicle were built to carry out the HIL bench test and actual vehicle experiment.The experimental results show that the vehicle slip angle and the yaw rate are always within a safe range,indication that the estimation algorithm constructed in this paper can meet the control requirements of ESC under actual conditions.