Fuzzy Control Of Automotive Anti-Lock System

In this dissertation, fuzzy control theory application on automotive anti-lock system is studied, based on combination of automotive theory and fuzzy control theory. After getting at shortcoming of previous general fuzzy control method, improvement and development are done, and simulation and test are carried out.The mathematic and MATLAB models of automotive dynamics, tyre and braking system are established, based on analysis on automotive braking process and ABS working principle. And the effectiveness of models are verified.General fuzzy controller of ABS is developed. Fuzzifier, defuzzifier and fuzzy rules are established. Fuzzy controller of ABS is developed with MATLAB fuzzy toolbox and simulated.Online interpolation fuzzy controller based on look-up table is developed to overcome shortcoming of general fuzzy controller and simulated.Convert fuzzy rules into algebraic expression to solve the deficiency of the two former, which cannot adjust control rules online. By putting emphasis on error-in-slip, look-up table of weight values on error-in-slip is established to adjust real-time control rules and simulated to regulate braking pressure.Another way to adjust real-time control rules. To avoid setting up look-up table, a method is developed to use absolute values of error-in-slip and change in error-in-slip as weight, and road identifying method is added and simulated, according to principle of feedback control.Real time hardware simulation and automotive test are done. Test and simulation results are compared. The conclusion testifies models and fuzzy control algorithm are correct, and algorithm can be improve continuously.