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Start from the automotive theory and fuzzy control theory , a combination of both , to study the application of fuzzy control theory in automotive anti- lock braking system (ABS) . Predecessors only the lack of conventional fuzzy control method , the control method on the improvement and development , and simulation . First analyzes the vehicle dynamics model , the tire model and the brake model and , on this basis , combined with the study requirements and existing conditions , removing the vertical damping of the tire , the establishment of a single wheel car model applies to the process of simulated vehicle straight line braking . Subsequent car straight line braking , the ABS system model (including a model of the vehicle , tire models and brake model ) using Matlab and Simulink software module , the basic fuzzy controller is designed , single wheel vehicle model ABS system brake computer simulation : braking of a quarter vehicle model simulation verify the correctness of the basic fuzzy controller . Fuzzy controller is designed based on the anti-lock control theory , to calculate the wheel slip ratio according to vehicle speed, wheel speed wheel slip rate . Calculated by reference slip rate slip rate of the error , the error rate of change as the input variables of the controller , the brake pressure as output , the completion of the fuzzy control fuzzy , fuzzy reasoning and fuzzy decision . Fuzzy reasoning , considering the different error levels , using different correction factors , in order to achieve self-adjusting fuzzy control rules . Simulation results show that the fuzzy controller better adaptive ability during braking , the slip rate of change is more close to the ideal change .
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