Optimization Research On Full-float Cab Suspension Of Semi-trailer Train

This paper first summarizes the present research situation in commercial vehicle cab ride comfort,analyzes the research actualities,and discusses the weakness in design then gets a conclusion that the researches on the cab ride comfort of semi-trailer-train are rare.Then put forward to use the theories of Mufti-body dynamic and random vibration to analyze and optimize the ability of isolating vibration for cab suspension system of semi-trailer-train.Subsequently,the Multi-body dynamic theories related to the vehicle cab ride comfort research are studied.The whole body vehicle ride comfort evaluation principle is established based on the random vibration theory and the standard of vehicle vibration.And the ADAMS that is used to the stimulation of the vehicle vibration is introduced simply.According to the analysis of semi-trailer-train' structure characteristics and parts vibration characteristics,put forward to build Multi-Body vehicle vibration simulation model including the flex frame.On the basis of considering the structures of main suspension and cab suspension,a parametrical Multi-Body vibration simulation model is built which could come true the optimization of the model according to changing the model parameters.Based on the mode analysis results of flex frame,normal mode and simulation analyses are used to study the whole Multi-Body vehicle vibration system.By normal mode analyses the mode frequency and mode shape can be got,and by simulation analyses the system's responds and vibration characteristics can be known.The average square of the point' acceleration after being filtered in ADAMS could be used to evaluate the cab ride comfort.Comparing the Multi-body systems analyses results with flex frame normal mode result,a conclusion can be get that the flex of frame has huge impact to the cab ride comfort.Build optimization mathematics model of the Multi-body whole vehicle system, then optimize the system,aiming at minimize the max value of acceleration's average square root of the seat.Result shows that the optimization is successful.All the study in this paper offers a valuable analysis and design method to cab suspension system in companies,and provide a feasible method to the similar Multi-body system study.