Research On The Optimization Of The Stiffness Matching Of The Front And Rear Stabilizer Bars On The Frequency Response Characteristics Of A Vehicle

Based on the research content of this paper,this paper introduces the background and significance of related research,mainly related to the vehicle’s handling stability and anti-roll bar.On this basis,the remaining problems are explained.Then the antiroll bar’s structural parameters and stiffness calculation methods are introduced.Based on this,the finite element simulation of anti-roll bar is made.In order to carry out the corresponding test verification on the basis of theoretical analysis,and complete the corresponding optimization,according to the real vehicle parameters,the structural dynamics models of the suspension and the whole vehicle were established.And the established model has been tested,the test results show that the model can output the curve of each parameter normally.After establishing the suspension and the vehicle model,the influence mechanism of anti-roll bar on suspension was analyzed theoretically.The suspension model is simulated and analyzed accordingly,the results show that the changes of suspension parameters and theoretical analysis can be echoed.The mechanism of the influence of the anti-roll bar on the vehicle’s characteristics is analyzed,then the corresponding simulation test is carried out for the built car model.The results show that the variation of parameter curve is consistent with the theoretical analysis of the vehicle.On the basis of theoretical analysis,a 3-DOF dynamics model of the vehicle is established.After Laplace transform,the transfer function of the vehicle’s transient characteristics such as yaw rate gain,roll angle gain and resonance frequency are obtained.Through DOE test analysis,the variation trend of vehicle’s transient parameters with the stiffness of the front and rear anti-roll bars was obtained.On the basis of theoretical analysis,based on the sine sweep steering wheel angle input simulation,the stiffness of the front and rear anti-roll bars was taken as the optimization variable,the vehicle transient characteristic index was taken as the optimization objective,the corresponding optimization algorithm was used to optimize the stiffness matching of the front and rear anti-roll bars.Finally,the corresponding iteration graph and the Pareto solution set graph are obtained.A Pareto solution was selected,and the transient and steady-state characteristics were compared with the original vehicle.The result shows that in the steering wheel angle sine sweep frequency input simulation,both the yaw rate gain value at 0.5Hz,maximum yaw rate gain value,the resonance frequency and the delay time of the yaw rate relative to the lateral acceleration have been improved.There are individual indicators have not reached the ideal state,but the changes in their values are within an acceptable range.Compared with the original vehicle,the main indexes in step steer input simulation of the optimized vehicle are improved.In the simulation test of vehicle steady-state characteristics,the understeer characteristics of the optimized vehicle are improved,and the roll Angle is increased compared with the original vehicle,but within a reasonable range of roll angle.Therefore,in general,the handling stability of the car has been improved compared to the original car.