Accurate Dynamic Modeling And Vibration Isolation Performance Optimization Of Truck

With the improvement of people’s consumption level,consumers have put forward higher demand for the ride comfort of vehicles,and the major automobile manufacturers also pay more attention to the optimization of vibration isolation performance of vehicles.The vehicle dynamics model is widely used in the optimization of vibration isolation performance of automobiles due to its low cost and short period of the research and development.At present,there are still insufficient research on vehicle fine modeling for trucks,the precision of parameter identification of component inertia is poor,the refinement and flexibility of modeling are insufficient,and the systematic optimization of the key vibration isolation component parameters of the cab is not possible,which makes the engineering application effect of the whole vehicle model worse.To this end,this paper takes a certain type of truck as the research object,combines the research and development demand of enterprises,and launches the research to the component inertia parameter acquisition,the whole vehicle fine modeling and the cab vibration isolation performance optimization.the main contents are as follows:1.This paper expounds the research background and significance of this subject,discusses the research progress and status quo of inertial parameter identification and multibody dynamics modeling at home and abroad,and further summarized the main research content of this paper.2.According to the problem that the mass line method cannot avoid the amplitude fluctuation and peak error interference,a weighted k-means clustering algorithm is used to optimize the problem.The inertial parameters identified by MPC2000 moment of inertia instrument are used as the standard values,and compared with the mass line method,the maximum relative error of the mass center coordinate of the improved method is less than3.16%,with a decrease of 1.65%;the maximum relative error of moment of inertia is 5.91%,with a decrease of 3.31%;the maximum relative error of inertia product is not more than4.06%,with a decrease of 4.06%.The error of inertia parameter all do not exceed 6%,which meet the requirements of engineering applications.3.Taking a certain type of truck of the enterprise as the research object,according to the inertia parameters obtained by the improved mass line method and the vehicle parameters provided by the enterprise,all subsystems of the truck are modeled sequentially.In order to verify the stiffness accuracy of the key components,the model stiffness simulation of the cab suspension system and leaf spring were carried out respectively,and compared the simulation results with the real vehicle test data for verification.The result show that the maximum relative error between test stiffness and model simulation stiffness of cab suspension system is less than 8%;the maximum relative error of static stiffness and dynamic stiffness of leaf spring obtained by bench test and model simulation is not more than 16%,and the stiffness verification of key components meets the requirements of engineering applications.Finally,the subsystem model is assembled into the vehicle dynamics model.4.Taking ISIGHT Software as the integrated platform and joint use of MATLAB and ADAMS/Car Software,obtaining the sample data by using The Optimal Latin Hypercube Design,and establishing the approximate model of vehicle dynamics model by Radial Basis Function Neyral Network,and the fitting error scatter plot is used to prove that the approximate model meets the requirements of engineering application.Based on the established approximate model,taking the minimum root mean square of acceleration in X and Z directions at the cab seat guide rail as the optimization objective,and taking the NSGA-Ⅱalgorithm to multi-objective optimization design of swing arm bushing coordinates,swing arm bushing stiffness,cab suspension stiffness and damping.Compared with the vehicle simulation data before optimization,the optimized root mean square value of acceleration in X and Z directions of cab seat guide rail decreases by 9.09% and 10.93%respectively,which indicates that the ride comfort of the trucks model is significantly improved.