Research On Finite Frequency Domain Control Strategy Of Intelligent Suspension Systems Based On T-S Fuzzy Model

As an industrial product that improves the quality of life,people have higher requirements for the driving comfort,safety,and handling stability of automobiles.Active suspension can more extensively adjust the performance of the suspension system,and it has become one of the effective means to meet people’s requirements.In the research on active suspension,the control strategy is undoubtedly the focus of attention,because different control strategies acting on the same physical structure will also produce hugely different control effects.In addition,the actual suspension system is not an ideal model,because there are variable parameters,and the actuator has problems such as uncertainty and time delay.How to meet the constraints of the suspension system while solving various practical problems is of great significance.Based on this,the main research contents of this article are:First of all,this paper establishes two pavement excitation models,namely,a block pavement and a non-stationary random pavement considering speed changes,to simulate actual vehicle driving conditions on the road.In addition,based on the classic quarter active suspension model,considering the uncertainty of system quality parameters,the T-S fuzzy model is used to describe the suspension system model more accurately.At the same time,the time-frequency response of the passive suspension system is analyzed to provide a basis for the design of the control algorithm.Secondly,considering the 4-8Hz frequency range where the human body is most sensitive vertically,based on the T-S fuzzy model and the generalized KYP lemma,a fuzzy limited frequency domain control algorithm is designed to effectively suppress the vibration response of a specific frequency band and improve ride comfort.At the same time,considering that the actuator is prone to aging,failure and other uncertain factors,which seriously affects the effect of the controller,in this regard,a non-fragile fuzzy finite frequency domain controller is designed,which can better handle the actuator.Simulation results show that the designed controller can resist the performance degradation caused by this kind of uncertain parameter disturbance.In addition,time-delay inevitably occurs in the implementation of the execution force and the transmission of signals,and the suspension is a real-time response system,and the time-delay will seriously affect its performance.In this regard,based on the T-S fuzzy model,this paper transforms a new constraint set into an unconstrained LMI,and associates it with the delay-related Lyapunov function through the projection lemma,and further generalizes the strict S-procedure.The design of a finite frequency controller with time-delay is promoted,and a non-fragile fuzzy finite frequency domain controller with time delay is designed.Simulation results show that the designed controller can well deal with the uncertainty and time delay of the actuator in the limited frequency domain.Finally,this paper uses the Quanser suspension test bench to verify the designed control algorithm.The experimental results show that the designed non-fragile fuzzy finite frequency domain controller considering time-delay can produce good control effects,which are consistent with the results obtained in the simulation.This shows that the control algorithm designed in this paper has good practical application value.