Study On Simulation Of Vehicle Ride Comfort Based On Pseudo Excitation Method

Ride of vehicle is the main performance index in reflecting if it's comfortable when we by car. There are two methods to evaluate ride of vehicle-sample car testing and numerical simulation. It's a long time for sample car to do a test, and much labor and money to be devoted make it not suited to today's fast update request. So numerical simulation is becoming much more important to be a assistance or even a main method. Vehicle ride performance modeling and simulation has an irreplaceable important role:first of all, it is not affected by testing conditions, avoid some random factors, comparable; secondly, in view of the existing automobile capable of simultaneously presented performance evaluation, but also on the new products of ride performance prediction. It can advance understanding of ride performance problems and resolved in a timely manner, can also optimize the matching relationship of parameters, to improve ride comfort index, shorten the design period, reduce the production cost, in early design to predict components of vehicle ride performance influence.Vehicle ride performance modeling and simulation at home and abroad have done a lot of research and its application, however, can find a simple, rapid and accurate to meet the research requirement of automobile modeling and simulation method, has been the automobile research and exploration of a very important research direction.On the research direction of the basis, combined with the national research and development project(10272033):National Natural Science Foundation of China:Based on manifold mechanical process virtual technology mechanics theory and method research. Pseudo excitation method on automobile ride comfort simulation system in-depth study and research, and its application to passenger car ride comfort experiment verification.This article is specifically:From the engineering application point of view, expand the stationary random vibration pseudo excitation method the basic theory, gives a rigorous derivation process, ultimately rich and complete virtual excitation method theory.Secondly, in the stationary random vibration pseudo excitation method based on, the vehicle ride simulation analysis, verified the validity of the application of virtual excitation method for solving. Through the comparison of analysis results and FFT method proved correctness and FFT method, at the same time, through the computation efficiency comparison than FFT method calculation speed.Furthermore, based on the finite element method and multi-body dynamics method, put forward to build the vehicle vibration structure model, assembly displacement vector, mass matrix, stiffness matrix and the total damping matrix. Through the preparation of procedures for automatic assembly of the vehicle structure vibration mathematical model, to verify the effectiveness of the proposed modeling method. Through the preparation of element analysis, overall analysis and restriction analysis of the program module, is simple and efficient structure system mathematical model of automobile vibration. At the same time, construct a kind of structure system convolutional functional, prove that the convolution variational zero and the system vibration equation equivalence. Furthermore, based on the variational theory, established a time-domain numerical method for general gradual recursion formula, application of gradual recursion formula, the stability analysis and numerical results show the time-domain numerical method accuracy and precision; the establishment of the cars nine degree of freedom vibration model, the application of new unit types at the same time, further improve the vehicle structure vibration mathematical modeling method.Finally, in automobile vehicle experiment conducted by the stationary and non-stationary Road on the basis of experiments, the pseudo excitation method, the modeling method and numerical method, for passenger car ride comfort, to stationary random road excitation and non stationary random excitation pavement of a more complete analysis, pseudo excitation method is proved in the surface analysis and the whole vehicle ride comfort prediction provides accurate and efficient analysis method.