Study On FUZZY-PID Cntrnol Method Of Vehivle Semi-active Suspension

With the rapid increase of people’s material living standards, people areincreasingly high demands for cars, they pay more attention to the comfort and safetyperformance of the car. How can cost-effectively improve vehicle stability andsmooth performance, is a big challenge in front of the car manufacturers. One of themost critical car systems is the suspension system. The suspension system play a roleof relieve external shocks and make a greater impact to the vehicle handling stability,ride performance and service life.. The automobile suspension system is the guarantee car bearing system with awheel or a bridge between each other with elastic contact and can transfer load,moderate impact, damped vibration and adjustment of the car body position and otherrelated device body, used to relieve disturbances on the impact of the car body, ensurethe ride comfort and handling stability. The semi-active suspension system in thecontrol quality is superior to the active suspension, according to the situation of theroad in between wheel and body active timely adjustment and produce a desiredsuspension control, to suppress the vibration of the body, make the suspension in theoptimal damping state. The semi-active suspension system control goal is to acquire agood ride comfort and handling stability, the traditional control theory and methodsare difficult to its performance fully. Fuzzy PID control with the fuzzy control andPID control two kinds of method, suitable for semi-active suspension system control.This paper will be automotive semi-active suspension system multibody modelof controlled object, first of all, based on system dynamics theory, a suspensionsystem multi-body model equation, Matlab/Simulink environment according to createdynamics equations of the two degrees of freedom to create the suspension model.Then, in the Matlab/Simulink to realize suspension system in the design of the fuzzycontroller and PID controller design and control rules defined as design variables.Finally, the simulation analysis to the whole system. In order to validate the controleffect of the fuzzy controller and the optimization of genetic algorithm performance,in50km/h under the speed of semi-active suspension system and passive suspensionsystem are compared and analyzed. The results of the semi-active suspension systemfuzzy PID control can improve the control effect of the fuzzy controller, improve the ride comfort of the car, at the same time also verified that the joint simulation method,the feasibility and accuracy.