Research On The Control Strategy Of Automobile Brake Performance Under Limited State

The control strategy of the automobile is a key research topic of automobile braking performance. The application of the automobile anti lock braking system(anti lock braking system, ABS) can greatly improve the vehicle braking safety.As an important brake safety control device in vehicles encountered unexpected emergency brake, to control the hydraulic brake wheel cylinder pressure, thereby regulating braking pressure, prevent wheel lock produces sideslip, drift phenomenon, to shorten the braking distance, ultimately ensure vehicle braking direction stability, improving the braking performance. Nowadays, ABS has been a kind of effective automobile braking standard configuration. The research on ABS control strategy has been carried out a lot. However, the use of ABS mechanism under the limit state of the brake can prolong the braking distance, affect the braking effect, how to optimize the control strategy and develop the brake safety control mechanism, so as to make the maximum improvement of braking performance will become a hot research in the future.Firstly, the significance, basic components and working principle of ABS system are introduced. The development status and development trend of the control strategy of automobile anti lock braking system are summarized. The influence of the existing ABS control strategy on the braking performance is analyzed, and the necessity and feasibility of improving ABS control method are clarified. Based on parametric modeling of Carsim software establish vehicle dynamics simulation model; were designed based on the slip ratio error PID logic threshold ABS controller and fuzzy PID controller; in the ADAMS software to establish a mechanical brake safety control mechanism model; construction of road surface of ice and snow、split road as emergency braking condition, combined with anti lock braking control, select vehicle longitudinal velocity, lateral angle, braking distance and evaluation standard, make of comparison of braking performance of the vehicle with the configuration of the original ABS controller, to verify the modified ABS controller effectiveness is used in the model building process. Simulation results show that the PID logic threshold ABS controller and fuzzy PID controller can effectively improve the braking effect of the vehicle under extreme conditions, and greatly improve the vehicle handling stability and driving safety. The brake safety control mechanism obtain shorter braking distance and better direction stability, the normal running of the vehicle is not affected.