Design And Research Of Lateral Control System Of FSAC Racing Car

Since the first FSC of FSAE(Formula SAE of china)was successfully held in 2010,it has gradually formed a comprehensive competition integrating FSC(fuel car race),FSEC(electric car race)and FSAC(unmanned car race).The development of the competition also highlights the automobile industry toward the new four(electric,intelligent,network,sharing)direction forward.The most technically demanding of the three was the FSAC.Motion control is one of the key technologies of unmanned racing,including lateral motion control and longitudinal motion control.This paper focuses on lateral motion control.In view of the special competition environment of FSAC and the large track tracking error of racing car at present,the lateral motion control system of unmanned vehicle is studied in this paper.On the basis of satisfying the security and operation stability,the control strategy and the design of lateral motion controller are studied,and the robustness of the controller is verified by the simulation of Simulink and Carsim.In this paper,the design and research of lateral motion control system for FSAC racing car are described as follows:1.Sensor layout and actuator design.Analyze the rules of the game and determine the modified design of the unmanned car with the original electric car.Analyze the working principle of the main sensor,determine the sensor selection through investigation and comparison,and determine the layout according to the rules of the game and the characteristics of the sensor.The steering actuator is designed based on the EPS principle to determine the servo motor and controller.2.Establishment of vehicle model.Taking the E05 of Guangdong University of Technology as the research object,the vehicle dynamics model and the kinematics model are established under the condition of ensuring accurate and stable path tracking.Based on the "magic formula",the mechanical properties of the tire were analyzed.Based on the theory of vehicle dynamics,a three-degree-of-freedom nonlinear vehicle dynamics model was established.Based on the Ackerman steering principle,a two-degree-of-freedom vehicle kinematics model is established.3.Controller design.Firstly,based on the model predictive control theory,a linear time-varying model predictive controller is designed.Then,based on the pure tracking theory,the algorithm is improved on the basis of the vehicle kinematics model,and the feedforward control based on the transverse preview deviation and the feedback control based on the course deviation are established.4.Simulation verification.According to the dynamic competition of FSAC competition,double shift line was determined as the simulation reference path,and the Simulink and Carsim joint simulation platform was built.The simulation of model prediction controller was carried out based on four working conditions of speed,the adhesion coefficient,prediction time domain and control time domain respectively,and the influencing factors of model prediction controller were analyzed.The simulation results show that the model predictive controller has a wider application range and is more stable than feed-forward feedback controller.