Research On Decoupling Of Height And Stiffness Parameters Of Air Spring

Air suspension,due to its variable height and stiffness,has become a consistent choice for many vehicles that comprehensively pursue smoothness,handling stability,and trafficability.It is increasingly widely used in passenger cars,high-end buses,and medium and heavy trucks.However,the height and stiffness parameters of the air spring,the key component of air suspension,are coupled with each other,which makes the height of the body and the vehicle stiffness cannot be adjusted independently,limiting the further development of the air suspension performance.In this paper,the decoupling of height and stiffness parameters of air spring is studied.In order to analyze the influence factors and volume change law of air spring height and stiffness,a more accurate simulation model is established.In order to check the model,the vertical static stiffness of the air spring is simulated and tested.The comparison between the simulation data and the test data shows that the air spring model has high accuracy.In order to obtain better decoupling effect,the influence factors of air spring height and stiffness and the change law of air spring volume are analyzed,which lays a foundation for the selection of decoupling air spring parameters and structure.Based on the previous model,the influence factors of air spring height and stiffness are analyzed.The simulation results show that the biggest factor affecting the height is the thickness of the airbag,and the biggest factor affecting the stiffness is the piston diameter.The bearing capacity and height adjustment ability of free diaphragm air spring and constrained diaphragm air spring are analyzed.The results show that the bearing capacity and height adjustment ability of the latter are stronger under the same initial conditions.The decoupling structure of two independent air chambers is proposed,and the axiomatic design theory of this structure is analyzed.The results show that the structure can realize the decoupling of air spring height and stiffness parameters.Starting from the target stiffness,combined with the vertical static stiffness calculation formula to complete the decoupling air spring structure size design.The finite element analysis method is used to analyze the decoupling effect of the height and stiffness parameters of the decoupled air spring.The simulation results show that the decoupled air spring can achieve continuous height change under certain load and stiffness,that is,the height can be continuously adjusted under the same stiffness,and the height and stiffness parameters are decoupled.In the research of air spring,a state needs to carry out multiple air pressure analysis,which has the problem of low simulation efficiency.Therefore,Abaqus software is redeveloped based on Python language.In this paper,the influence factors of air spring height and stiffness and the law of volume change are analyzed.A new scheme is proposed for the decoupling of air spring height and stiffness parameters.It is of great significance to further improve the performance of air suspension.