Research On Ride Comfort Of Automobile Active Suspension Based On PID Control Strategy

With the advancement of the automotive industry technology and the increase in people's requirements for vehicle performance,how to more effectively improve the various performances of automobiles,including ride performance,handling stability,and safety performance,has attracted more and more attention from researchers.At present,the suspension systems used in automobiles can be divided into three types: passive suspension,semi-active suspension,and active suspension.Comparing these three different types of vehicle suspensions,passive suspensions have the largest use because of their low cost.However,passive suspensions can only provide good vibration isolation on the road surface under certain road conditions.As for the complicated and changeable road environment,the passive suspension cannot show good adaptability to the road environment,and often cannot meet people's requirements for automobile performance.Control strategy is the soul of active suspension,and it is also the key to determining the performance of active suspension.The PID algorithm has a simple form,is easy to implement,and has a wide range of applicability.PID control strategies often show good control results.The controller designed based on the PID control algorithm will show different control effects due to changes in control parameters.This paper combines the related research results of scholars at home and abroad in the past to set the parameters of the PID controller for active suspension did research.First,the time-domain simulation models of B-level and C-level pavement were established in MATLAB/Simulink environment,and according to the mechanical models of passive suspension and active suspension,sub-simulation models of 1/4 passive suspension and 1/4 active suspension are built.Secondly,this paper establishes a PID controller in combination with the PID control algorithm,and designs a PID controller with enhanced filtering function without changing the basic principle of the PID control algorithm.At the same time,based on fuzzy control principles and fuzzy + PID joint control principles,fuzzy controllers and fuzzy + PID joint controllers were established respectively.In addition,combined with the sub-simulation model of 1/4 active suspension,the simulation model of 1/4PID control active suspension,1/4 fuzzy control active suspension simulation model and 1/4 fuzzy + PID joint control active suspension simulation are established model.Third,given that the control parameters of the PID controller are directly related to the control quality of the PID controller,this article proposes two implementations of two parameter tuning schemes that optimize tire dynamic displacement as the main goal and optimize suspension dynamic stroke as the main goal,the control parameters of PID controller were tuned by using range analysis method and orthogonal test method combined with quadratic surface method.Through the comparison of the two implementation schemes,the parameters set with the main goal of optimizing the dynamic travel of the suspension as the optimal control parameter combination of the PID controller are selected.Finally,from the comparison of simulation results: under the input condition of C-level road surface,in terms of improving tire dynamic displacement,compared with passive suspension systems,fuzzy control,fuzzy+PID joint control,PID control are respectively reduced by 0.84%,0.3% and 0.5%;in terms of improving suspension dynamic travel,compared with passive suspension systems,fuzzy control,fuzzy + PID joint control and PID control are respectively reduced by 17.99%,23.96% and 24.1%;in terms of improving the vertical acceleration of the body,compared with the passive suspension system,fuzzy control,fuzzy + PID joint control and PID control are respectively reduced by 7.58%,12.47% and 12.96%.Under the input condition of B-level road surface,in terms of improving tire dynamic displacement,compared with passive suspension systems,fuzzy control,fuzzy + PID joint control,PID control are respectively reduced by 0.91%,-0.3%,0.48%;in terms of improving suspension dynamic travel,compared with passive suspension systems,fuzzy control,fuzzy+PID joint control and PID control are respectively reduced by 19.87%,23.37% and 24.08%;in terms of improving the vertical acceleration of the body,compared with the passive suspension system,fuzzy control,fuzzy + PID joint control and PID control are respectively reduced by 8.65%,12.27% and 12.64%.Through the analysis of the test results of the three smooth performance indicators of the suspension system,through the setting of control parameters,PID control active suspension system has better ride performance than passive suspension system,fuzzy control active suspension system and fuzzy+PID combined control active suspension system,that is theoretically proved that setting the control parameters of the PID controller can tap the control potential of the PID controller and improve the smooth performance of the automobile suspension system.