Simulation And Optimization Of Anti-Rollover Stability Of Passenger Car Based On Rigid-Flexible Coupling

Rollover accidents cause huge threat to people’s lives and property.Besides,passenger car is more prone to rollover for its large inertia,high center of mass,so to improve the anti rollover stability is very crucial to the safety of passenger car.Among all parts of vehicle structure,suspension plays a decisive role in vehicle handling stability and ride comfort.This paper will take a 12 m bus as the research object,do optimization on coordinate locations and stiffness matching of the suspension by using simulation technology,in order to improve the anti rollover stability.Firstly,based on a 3 degree of freedom rollover model,analyzes the mathematical relationship between the suspension coordinates and vehicle roll angle;Laplace transform is used to convert the rollover equation,take it as a second order system with lateral acceleration as the input and roll angle as the output to verify the response between its input and output.The two focuses provide theoretical basis for later optimal design.Secondly,with finite element method,a rigid-flexible coupling model is built.The model is verified through the analysis of static balance and the wheel jump test,for the height of mass center of the assembly model is matched with the real bus with an error of 6.71% and the variation of four wheel alignment parameters is within the reasonable range.According to National Standard,write drive documents,so the road simulation tests are carried out.Since the traditional method did not consider the interaction of factors,which may not achieve the correct optimal results,therefore,take the response surface method into account.The final simulation results show that the optimized vehicle has improved the anti-rollover stability in steady circle steering simulation,snake-like simulation and step simulation,the body roll angle is decreased by 11.29%,33.33%,26.88% respectively.In this paper,the whole research process is studied on ADAMS simulation platform.The coordinates location and stiffness of suspension get optimized by taking the response surface method.By comparing the changes of roll angle in the optimization results,to know that the roll angle of the body is reduced significantly and the anti rollover stability of passenger car.have been effectively improved.In addition,a set of process and method of suspension optimization is proposed,which may has a reference value for the future simulation application.