Research On The Control Strategy Of AFS System Based On The Driving Simulator

The economy of our country is in the period of quick development,and the number of automobile is increasing continually,especially the number of car.At the same time,the number of traffic accident is also very large,which causes huge loss to the country and its people.So how to enhance the security of driving and reduce the number of traffic accident becomes the important researching content of intelligent traffic area.Statistic data indicates that the rate of traffic accident at night is 3 times that of daytime,the rate of traffic accident on the road of good illumination is 30% that of bad illumination.So research of the front light of automobile is very important and AFS is comes into being.AFS is also called Adaptive Front-Light System.Its basic principle is as follows: When the automobile enters into the curve or other special road,it will bring the change of the velocity sensor and angle sensor because of the change of automobile velocity and the angle of steering wheel.The ECU catches these changes and sends instructions to the controlling unit of the front light.It can decide the angle of illumination of the front light when these changes are disposed by the controlling arithmetic in the ECU.Adaptive Front-Light System can be adaptive to the change of velocity and road condition better.It can enlarge the ken of the driver,enhance the safety of driving and reduce the rate of traffic accident.This text mainly researches the controlling arithmetic based on the Adaptive Front-Light System of the driving simulator.The Adaptive Front-Light System adopts the closed-loop to improve the controlling performance and controlling precision by using the PID arithmetic and fuzzy arithmetic.This text researches the signal gathering method of the driving simulator firstly. It gathers angle of steering wheel,gun and so on from driving simulator;secondly,the text mainly researches the relationship between the gesture of the automobile and the angle of the front light.These relationships include the relation among the angle of front wheel,velocity and left-right angle of the front light,the relation between pitching angle of the automobile and level angle of the front light,the relation between the cg and level angle of the front light;thirdly,the text researches the foundation of mathematic model of the Adaptive Front-Light System.This mathematic model is founded through system identification of least-square means. This method is simple and pellucid;research of the controlling arithmetic is the keystone of this text.This text studies the MATLAB simulation of the arithmetic of PID control and fuzzy control based on the mathematic model of system.The text also analyzes the dynamic performance of the system and the result indicates that fuzzy control is better than PID control;finally,experiment is done and the dynamic performance of the system is analyzed by using the tool of MATLAB.The result indicates that the researching method in the text is feasible and the purpose of the text is achieved.