| Automatic parking system has been regarded as a hot number of automobile industry,it can be alleviate driver's physical and brain's work intensity. Automatic parking system is very complicated, and it needs high cost, while building its mathematic model and applying to suitable control strategy to perform simulation analysis is not only convenient to flexible adjusting design scheme and optimizing design parameter, but also decreases scientific research cost, shorten develop cycle. Path planning is the key problem of automatic parking system, solving this problem and exploiting content parking control is the precondition of designing automatic parking system Vehicle localization is the base of the whole parking system, action control solves the problem of"How should I get there?",by coming true them and associating with parking control we can design the whole automatic parking system.The intention of this thesis is designing the roof of automatic parking system, in which process the main content is studying the arithmetic of turning control and orientation by using ultrasonic sensors, the secondary aim is discussing action control.In Chapter One, it generally introduces the developing actuality of autonomous parking, the significance of automatic parking, the system of assistant backing a car and alarming in advance, the research and application in vehicle industry of fuzzy algorithm.Put forward the three main WWH problems, in the end, the main task of the paper is indicated combined with the research objects.In chapter two, the research on the simulation of automatic parking by using fuzzy controller is carried on. The first task is make sure of the car using for simulation and the size of garage, and then study the kinematic mode of the car, bring forward the description of the model by equations. Abstract the rule of fuzzy control on the base of expert experience, and then set up model using simulink,carry through the simulation and compare the result. The core of this arithmetic is the repository composed by"IF-THEN"rules, establish repository, achieve fuzzy consequence, gain the angle rate which change into the angle rate of the walking electromotor which drives the steering wheel by feeding back to the car.In chapter three, the research on the optimization of fuzzy controller parameters by using Genetic Algorithms is carried on. On the base of in-depth study of Genetic Algorithms, this chapter achieves the optimization procedures of Genetic Algorithms by using the mixed programming methods of Matlab and VC, which fully utilize the dynamic memory allocation technic and the pointer operation of VC and Matlab/Simulink powerful functions of calculation and modeling, in this way, it can play their advantages respectively , enhance the operating efficiency of the program. The parameters of fuzzy controller membership function by analyzing the optimization results can not only complete the task of automatic parking simulation, but also get a better simulation results.In chapter four the paper researches on the orientation arithmetic of automatic parking system. Analyse the disposal of many ultrasonic sensors and the problem of avoiding signal interference of several ultrasonic sensors, and then carry about the orientation arithmetic, on this base discuss the drive of ultrasonic sensors and data gathering, by measured the data calculate the posture of the car, then using fuzzy controller computation obtain the Spreading horizontally angular speed of the body of the car.Regarding the walking electromotor which drives the steering wheel to carry on the plan elaboration, by further calculating the Spreading horizontally angular speed of the body obtain the work requirement of the walking electromotor which drives the steering wheel.This article parked has done the research on the fuzzy controller, the ultrasonic localization and the action control, which has built the foundation for the platform of automatic parking system.
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