Research On Commercial Vehicle Electronic Stability Control Strategy

When the vehicle is running,it will always encounter many extreme conditions,such as high-speed emergency lane change and sharp turn,etc.At this time,the vehicle is prone to slip and other dangers.When the vehicle is in danger of slipping or other dangers,the cost is often heavy.For trading trucks,the cost will be even more tragic.The appearance of the ESC system has effectively reduced the occurrence of slipping and other phenomena,effectively improving the handing stability of the vehicle.In order to improve the active safety performance of China's trading trucks,the Ministry of Transport takes the lead in organizing the research and formulation of the "Technical Conditions for the Safety of Commercial Trucks." The electronic stability control system(ESC)is also a mandatory installation system of this standard.Therefore,this paper takes the formulation of the standard as an opportunity.Studying the control strategy of commercial vehicle electronic stability system aims to provide a theoretical basis for the promotion and application of ESC system in the trading trucks.In this paper,through the study of the ESC system,the control strategy is determined,where the yaw rate and the centroid slip angle are used as the control variables.And the fuzzy PID was used as the control method.By analyzing the dynamics of the test vehicle,a differential equation of motion is established.And based on this differential equation,a 2DOF reference model of the Simulink is established,and the steady-state value of the control variable is determined.Based on the TruckSim,a complex nonlinear dynamic vehicle model was established.Taking a two-axle truck as the test vehicle,a vehicle performance test system is built and records the lateral acceleration data of the vehicle pylon course slalom test.Based on the data,the accuracy of the Simulink reference model and the TruckSim vehicle dynamics model are verified and improved.This paper proposes a control strategy on account of fuzzy PID control algorithm,and designs upper and lower double-layer controllers.The upper controller takes the error and change error of vehicle yaw rate as the input to design a yaw rate fuzzy PID controller,and takes the error and change error of vehicle slip-angle as the input to design a slip-angle fuzzy PID controller.The output of the yaw rate fuzzy PID controller and slip-angle fuzzy PID controller are calculated by the weighted module to calculate the additional yaw moment.The lower controller designs brake wheel selection module and brake force distribution module based on MATLAB/Stateflow,and the additional yaw moment is converted into single-wheel braking force.With the co-simulation environment of TruckSim and MATLAB/Simulink,the paper conduct the typical condition simulation,which consist of Step Steer test,Fishhook test and Double Lane Change test.The simulation results show that the fuzzy PID double-layer controller for the commercial vehicles is effectively improved the handling stability of the vehicle.