Research On Braking And Control Performance Of Disc Type Magneto-rheological Antilock Brake System

Magneto-rheological fluid(MR)is a new type of intelligent controllable material.Its rheological properties show millisecond,continuous and reversible rheological properties with the change of applied magnetic field.Magneto-rheological brake can realize linear control of braking moment by adjusting the current to change the yield strength.In the near future,with the fast development of electric vehicles,a great number of researchers take focus on the technology of on-line control braking,as well as gradually raising the requirement of automobile braking system.The traditional hydraulic braking system always causes the phenomenon of braking delay and pulsation when braking,because of its own structural characteristics.Moreover,the chassis of traditional hydraulic ABS(Antilock Brake System)is complex,which increases the probability of accidents.At present,the research of MR brake is still in the developing stage,and it is a preliminary attempt for its application in ABS.Therefore,the research on MR ABS brake system is of great significance.The main contents of this paper include:(1)Referring to the relevant literatures,this paper expounds the shortcomings and future development trend of automobile braking system,and introduces the domestic and foreign background of MR fluid,as well as the status of traditional ABS braking system.(2)The ABS system of automobile based on a disc MR brake is studied.The static electromagnetic field of this disc MR brake is analyzed by finite element method using ANSYS software,and a torque measuring test bench is built to get the its braking torque.(3)The hardware configuration and software model design of the hardware-in-the-loop simulation test of braking torque control are carried out.The hardware-in-the-loop simulation platform combined with MATLAB/Simulink is built by using Arduino development board and L298N driver.Later,the preliminary port test is carried out and the step control test,sinusoidal following test and braking force holding test of braking force are carried out by using PID control method.(4)According to the mathematical characteristics of the braking torque of MR brake,the simulation model of MR brake is established in Simulink,and its correctness is verified.Based on the designed MR Fuzzy Logic Sliding Mode Controller(FLSMC),the braking system of a quarter vehicle model is also established and the simulation and hardware-in-the-loop simulation tests of MR ABS are carried out to verify the rationality of MR ABS control process.