Study On Nonlinear Damping Characteristics Of Suspension System Of Dump Truck

In order to make the suspension system of mining dump truck have better damping performance,whether the damping parameters of hydraulic shock absorber are reasonable is very important.Therefore,this paper studies the nonlinear damping characteristics of the hydraulic shock absorber of the suspension system of a certain type of mining dump truck,which analyzes the impact of asymmetric damping on the vehicle damping performance,and applies it to the damping multi-mode switching control system of semi-active suspension.The specific research contents are as follows:1)The AMEsim simulation model of the hydraulic shock absorber is established,and the cross-sectional area of the throttle hole of the shock absorber is analyzed by equivalent transformation of the asymmetric damping into the recovery and compression valve.Under the condition of equal equivalent damping coefficients,the cross-sectional area ratio of the throttle hole is proposed as 1/3,1 and 3 respectively.The mathematical model of hydraulic shock absorber and the Matlab/Simulink solution model are founded to prepare for the comparison and verification of AMEsim model.2)The Recurdyn 1/4 vehicle suspension system dynamics model is builded and co-simulated with the AMEsim shock absorber model.The vehicle vibration response is obtained,which is also compared with the results of Simulink mathematical model.Sinusoidal excitation is used to analyze the influence of excitation frequency on vehicle vibration performance under three groups of orifice cross-sectional area ratio scheme.3)The Recurdyn dynamics model of the suspension system is founded and co-simulated with the AMEsim hydraulic system model.The influence of the cross-sectional area ratio of the throttle hole on the vehicle vibration reduction performance under different road spectrum levels and vehicle speeds is analyzed and optimized.4)The control system of damped multi-mode switching semi-active suspension and its Simulink model are established,and the suspension damping force is provided by the AMEsim model of damped multi-mode switching hydraulic shock absorber,and the asymmetric damping ratio of each damping mode is determined by the above method.Compared with the ceiling damped semi-active suspension control system and the original dump truck passive suspension system,the damped multi-mode switched semi-active suspension control system can effectively reduce the vehicle vibration level,and it is also verified the importance of asymmetric damping to the semi-active suspension control system.The research can provide a design basis for the selection of hydraulic shock absorber of passive and semi-active suspension system of mining dump truck,and also provide a theoretical reference for the design of suspension system of other engineering vehicles and agricultural vehicles.