Study On Characteristics Of Vehicle-road Coupling Vibration System Based On Semi-analytic Solution

In highway transportation,the transportation of large flow and high load goods often leads to road surface damage and worsens the unevenness of the road surface.This in turn affects vehicle performance,such as reducing vehicle smoothness,affecting driving stability and safety.Therefore,vehicles and roads are a coupled vibration system,and studying the vibration characteristics of this coupled system and optimizing its parameters is of great significance for improving vehicle performance and reducing road damage.This article focuses on the coupling vibration system between vehicles and deformable roads,and conducts in-depth research on different coupling models in terms of dynamic response calculation,vibration characteristics analysis methods of vehicle road systems,and parameter optimization.The main research contents are as follows:(1)Considering the deformable characteristics of the road,the elastic characteristics of the foundation,and the unevenness of the road,a vehicle road coupled vibration system model is established and the coupled system response is solved.The road foundation adopts the Winkler model,and the road surface is simplified as finite and infinite Euler Bernoulli beams.The numerical solution of the coupled vibration system response between the vehicle and the finite length road is obtained through modal superposition method,and the analytical solution of the coupled vibration system response between the vehicle and the infinite length road is derived using integral transformation method.(2)Apply the residue theorem to solve the semi analytical solution of the coupled vibration system response between vehicles and infinite roads.By analyzing the integral domain characteristics of the integrand function,the application conditions of the residue theorem in the response calculation of vehicle road coupling systems are obtained.According to the characteristics of complex coefficient quartic equation under different coupled system models,the expression of integrand can be obtained by formula method or numerical method combined with residue theorem.Then,the poles of the integrand are obtained by Newton’s method,and the semi analytical solution of the response of the coupled vibration system is obtained by using the residue theorem.(3)Compare and analyze the response calculation methods of different vehicle road coupling system models,and discuss the use of numerical and semi analytical methods.Establish a mobile coordinate system to analyze the vertical displacement and acceleration of vehicles,as well as the road displacement at the contact point between the vehicle and the road.The results indicate that the vehicle infinite road coupling model is superior to the finite road coupling model.The effective application of semi analytical solution in vehicle road coupling response calculation was verified from the perspective of simulation and calculation accuracy,and parameter studies were conducted on the two coupling systems.(4)In order to improve vehicle smoothness and road friendliness,particle swarm optimization algorithm is used to optimize the vertical acceleration of vehicle and the lateral displacement of road surface for single objective respectively,and the best parameter group within the given parameter range is obtained.Furthermore,multiobjective optimization was carried out on the vehicle road vibration coupling system to obtain the Pareto optimal solution set of the response.After optimization,the vertical acceleration of the vehicle was reduced by 9.62%,and the road displacement was reduced by 42.29%.This study has important theoretical guidance significance for the optimization and control of vehicle smoothness and road friendliness under vehicle road coupling,and provides theoretical reference for the design of vehicle suspension systems.