Fuzzy Control System Research Of Vehicle Hydraulic Active Suspensions

A suspension system of a vehicle is an important part of a vehicle.The traditional passive suspension cannot meet the requirements of vehicle performance.The active suspension of a vehicle has great advantages in performance compared with the traditional suspension.A well-functioning suspension system can improve the comfort of the car and play a very important role in safety.With the higher and higher demands on vehicles and the correspondingly higher suspension performance,the research on the control method and control device of active suspension has important theoretical value and social benefits.On the basis of investigating and studying the current situation of the development of hydraulic active suspension in domestic and foreign vehicles,firstly,the T-S fuzzy model of the suspension system is established for the hydraulic active suspension system of a quarter vehicle,the continuous fuzzy controller and the digital fuzzy controller of the suspension system are designed respectively,and the solution method of continuous fuzzy controller and digital fuzzy controller gains are given in the form of linear matrix inequality.Then,based on the stability theory of Lyaponov,the stability and constraint requirements of the active suspension closed-loop system are analyzed theoretically.Finally,the validity of the designed controllers is verified by simulation.For the digital control of a quarter-car hydraulic active suspension system,a single chip microcomputer of STM32 series is used as the control core and the relevant hardware circuits and software programs are designed.The hardware circuit can collect the spring mass speed,un spring mass speed,suspension displacement,tire displacement and servo valve displacement of the system,and store and display them by using the data storage circuit.The CAN bus data are transmitted to the vehicle’s operating control system.The software part of the system mainly includes the main program of the single-chip microcomputer,the Clock driven subroutine,the CAN bus sub-program and the display sub-program.Control of the system is achieved through these programs.