Research On Key Technology Of Automobile Vibration Model Establishment And Verification Based On Real Vehicle Driving Condition

With the rapid development of computer technology,CAE technology has been used more and more often in the development of automotive performance.How to establish an accurate vehicle vibration model has become a big problem.At present,the vehicle comfort simulation analysis mainly focuses on the simulation based on the theoretical model.Most of them use the common model to build the vehicle,and input the standard random road spectrum to make the vibration simulation,both the parameters of the model and the input of the road are quite different from actual situation.So,it is difficult to guarantee the accuracy of the simulation results.Based on this,this paper focuses on the key technologies of vehicle vibration modeling technology,model parameter extraction technology,road surface spectrum generation technology and verification technology,which is based on the actual driving condition of automobile.Firstly,based on the analysis of Lagrangian mechanics and multi-body dynamics theory,simplify and equivalence the complex vehicle system.According to the structural characteristics and parameters of the target vehicle,establishes the eight degree freedom vibration mathematical model of automobile.At the same time,paper established the former McPherson suspension model,the rear torsion beam rigid and flexible coupling model,the tire model and the pavement model by using ADAMS/View.Then,set up the high-performance synchronous data acquisition system.According to the enterprise test specification,the acceleration sensor,the displacement sensor and the six-force sensor are arranged in the relevant position.The key load is collected in a vehicle test field based on the actual driving condition,Providing basic data for road surface generation and simulation verification.At the same time,the suspension spring and shock absorber stiffness test system were constructed by using MTS electrohydraulic servo system.The key parameters such as spring and shock absorber were tested and calibrated to improve the accuracy of the suspension model.Next,established the dual-mass vibration system theoretical model of the automobile,research the method of using differential equation calculating the roughness of the road,Using the sprung and unsprung mass acceleration data collected by the actual driving condition solve and verify the pavement roughness.According to the present pavement unevenness density standard of GB and ISO,the mathematical expression equation of non-standard road surface density under the condition of real vehicle driving condition is deduced to quantitatively express ADAMS/Sayers road model,GB and ISO,which solved the problem of practical application of arbitrary pavement in multi-body dynamics simulation.Finally,combined with the multi-body dynamics model of automobile vibration,the non-standard pavement spectrum under the condition of real vehicle driving condition is taken as the input.The dynamic simulation of the system is carried out,and the simulation accelerate data of driver's seat slide position,the four wheel sprung mass position was carried out.The results show that the RMS and the peak-valley error are small,the spectrum analysis are in good agreement,the simulation is accurate and reliable.