Ride Comfort Analysis And Optimization Under Multi-working Conditions Of Van Transporter Based On RECURDYN

With the rapid development of automobile industry.Many companies have been developing commercial vehicles from satisfying the basic transport demand to the pursuit of higher performance,such as ride comfort and handling stability.Van as the most common logistics transport vehicle,in the long-distance driving,more attention should be paid to the ride comfort.In order to relieve the fatigue of the driver,and ensure the safety of driving.In this paper,the vehicle dynamic model is built by using RecurDyn which is the multi-body dynamics software,and the parameters that affecting the ride comfort are analyzed and optimized.This paper introduces the research status of ride comfort at home and abroad and the dynamic modeling method of leaf spring,including finite element method,beam method,medium plane method and three link method.Then introduces the basic theory of RecurDyn in detail,including relative coordinate system,kinematics equation of relative coordinate,function expression,metamodel optimization algorithm and secondary development.The dynamic model of leaf spring is built in RecurDyn based on SAE three link method.Considering the hysteresis characteristics of the friction contact between leafs in actual work of leaf spring,the sliding friction model in revolution joint is proposed to simulate the contact friction between the leafs.In order to ensure that the mechanical properties of leaf spring model are consistent with the actual situation,the main parameters which affect the stiffness and hysteresis characteristics of leaf spring are found by DOE experiment.Build the finite element model of leaf spring,get the time-displacement curve as the target curve,identify the selected parameters using meta-model algorithm,and obtain the three link model of leaf spring which satisfy the design requirements.In order to obtain the dynamic model of vehicle.The subsystem of cab,carriage,front and rear suspension and tire model is built in RecurDyn,then assemble the subsystems according to the constraint relationship.In order to improve the simulation efficiency of vehicle,simplify the pulse road and random road,then the simulation of the different speed of the vehicle is carried out under the pulse and random road.The ride comfort test of physical prototype is conducted under different speeds of pulse and random road.Compared with the simulation results,the accuracy of model is verified.The influence of the suspension and cab suspension parameters is analyzed based on DOE experiment,which to determine the range of the design variables.The constraint condition is suspension bias,suspension dynamic deflection and relative dynamic load of tire.According to GB/T 4970-2009,choose the vertical weighted acceleration RMS of the cab floor as objective function,and edit its calculation program using C# in RecurDyn/ProcessNET.The model is optimized based on metamodel optimization algorithm,and the improved scheme is proposed for the ride comfort of physical prototype.