Path Planning And Tracking Of Automatic Parking System

With the increase in car ownership,parking is difficult to become a common phenomenon.The narrow space of the parking spaces led to frequent accidents during the parking process.The emergence of automatic parking system,can effectively avoid the accident in the parking process.Therefore,the automatic parking system has become the research hotspot of domestic and foreign enterprises and research institutions.In this paper,the vehicle is driven by the front wheel drive,and the parking path is planned by using the polynomial.The fuzzy controller is designed to track the parking path.Firstly,this paper analyzes the working condition of the parking process and establishes the kinematic model of the vehicle.Through the analysis of the parallel parking spaces,vertical parking spaces and inclined parking spaces,the parking detection method of automatic parking system based on ultrasonic sensor is determined.Through the MATLAB / Simulink software platform,the parking detection logic is simulated and the feasibility of the parking detection method is verified.Secondly,according to the geometric relationship of the vehicle,the minimum parking space size and the parameters needed in the path planning are determined.At the same time,through the analysis of the parking process of parallel parking spaces,vertical parking spaces and lathe parking spaces,respectively,to determine the parking starting location area of different parking spaces based on the shortest parking path.To lay the foundation for the path planning of automatic parking system.Thirdly,in this paper,the polynomial is used to plan the parking path.Path planning using a polynomial calculation is simple.Can guarantee the path curvature continuous,at the same time to meet the requirements of the steering system.The position constraint,attitude constraint and obstacle avoidance constraint of the planning path are determined.The available parking paths are calculated by MATLAB / Simulink in three types of parking spaces.Lay a good foundation for path tracking.Finally,the driving experience of the driver is summarized and the input,output,membership function and fuzzy logic of the fuzzy controller are determined.And through MATLAB / Simulink software platform,path tracking is simulated.The validity of the fuzzy controller can be verified by analyzing the position error of the midpoint of the rear axle,heading error and front wheel steering angle.