Based On Slip Rate Real-time Anti-lock Braking System And Its Simulation Research

Anti-lock braking system (Anti-lock Braking System) ABS as a typical representative of active safety devices, the main purpose is to prevent an wheels hugging, maintaining vehicle directional stability and manageability and shorter braking distances when the emergency brake, so that the effectiveness of brake performance into full play. Target of the best ABS based on combination of vehicle dynamics control system is to control wheel slip rate, which involves a series of key technical studies, such as the wheel speed signal processing method, vehicle speed estimation method and the best slip rate estimation methods. In order to improve the logic of the traditional limitations of ABS threshold, The main studied of this article is key technology and implementation of the above-mentioned methods based on the slip rate of car anti-lock braking system.In this article based on summing up previous work, mainly focused on automotive ABS slip rate control algorithm for real-time.First of all, the article analyzes the working principle of ABS, introduced the current commonly used control methods of ABS, including the logic threshold control method and fuzzy control methods. According to the basic structure of ABS, establish the anti-lock braking system model, using Newtonian mechanics to establish one-wheel vehicle braking model, and select the magic formula as the vehicle braking model tire model.Then, describing the wheel speed signal acquisition and processing, study the advantages and disadvantages of the frequency of the measurement method and measuring cycle method, analysis of the two methods wheel speed signal measurement error and using a joint velocity method to calculate the wheel speed;At the same time, because of the problem of sensors and other equipment for the expensive and in order to make front and rear wheel slip rate remained the same or both tend to hugging, studied the vehicle velocity estimation methods, which can be more precise calculation of real-time vehicle speed.In addition, because different road surface have different adhesion coefficient so establish road recognition module, and by the velocity of the wheel speed and vehicle to calculate real-time slip rate, according to different road conditions to determine the optimum slip ratio, and controlling the corresponding variable of wheel slip rate to always maintain wheel slip rate in the best condition, thus ensuring the ABS system more effective to play a role in ensuring security and stability of the wheels.