Parametric Modeling And Multi-body Dynamics Simulation Analysis Of Nonlinear Rubber Bushing

Vehicle driving stability has an important influence on users' subjective feelings and objective evaluation of vehicles.Road excitation causes vibration of vehicle body during vehicle driving,resulting in poor ride comfort of vehicles.Therefore,vibration reduction system must be applied to improve vehicle performance.Among them,the spring and damper of suspension system are mainly used to reduce the low frequency vibration of vehicles,while high-frequency vibration is usually treated by rubber bushing at the suspension.Rubber bushing mainly includes cushioning,transmitting load and reparation tolerance.It is necessary to establish an accurate dynamic model of rubber bushing to increase the reliability of the simulation results when using the multibody dynamic analysis software Adams for the early development and design analysis of the vehicle.Therefore,based on the static and dynamic test of rubber bushing,a rubber bushing model considering stiffness nonlinearity is proposed,and the simulation software is used to analyze the vehicle response characteristics of the model,and the validity of the model is verified.The main contents of this text are as follows:(1)Outline the internal microstructures and mechanical effects of rubber materials.The static and dynamic loading tests of a suspension rubber bushing are carried out in different working conditions.Then processe and analyze the test results.obtain.The static and dynamic property and amplitude-frequency correlation of the rubber bushing are obtained,which provides the experimental basis for the subsequent modeling.(2)The theoretical model of the existing rubber bushing is introduced,including the Kelvin-Voigt model,the Maxwell model and the Berg model.The advantages and disadvantages of the model are analyzed,eventually build a model of rubber bushing using three parts which are superelastic,friction and viscoelastic.the model parameters suitable for multiple working conditions are get after fitting the model with the experimental data.(3)Based on the rubber bushing model proposed in this paper,the liner bushing model is replaced by the Gforce six direction force element,so that the nonlinear expression of the mechanical characteristics of the rubber bushing can be realized.The model of front suspension is established in Adams/Car.K&C test and dynamic stimulation simulation are carried out for the front suspension of the nonlinear rubber bushing and linear model.The results are analyzed and compared to verify the validity of the model.(4)On the basis of the front suspension,add its residual subsystem to assemble the whole vehicle model,establish the random pavement spectrum,The ride comfort simulation of the vehicle model is carried out under the random road document and the convex platform.Then the response and differences of the linear model and the nonlinear model are compared and analyzed,which verifies the necessity of considering the nonlinear rubber bushing in the vehicle simulation analysis.