Study Of Mathematical Model Of Hydraulic Pressure Controlled Shock Absorber And Development Of Measurement System

Shock absorber is an important damping component in automotive suspension system, and its performance influences the matching quality of suspension system, playing a significant role in improving ride comfort and safety of automobiles.As the shock absorber is one of the most non-linear and complex elements to model, before the study of the vehicle system dynamics simulation, the mathematical models of shock absorber has to be built. But when we develop the study of the vehicle dynamics simulation and the control algorithms of semi-active damper, the common way to build parametric model which is usually used to design the shock absorber has several problems, such as its form is complex, some of its parameters are difficult to obtain and has to consume lots of time. In order to avoid these problems, this paper utilizes the modeling method developed by Reybrouck, details the mathematical model of a hydraulic pressure controlled shock absorber, and the parameters of the model are obtained by parameters identification.In this paper, the main task is introduced as follows:Firstly, considering the influence of the valve structure, this dissertation details the damper model whose valve parameters are grouped to global parameters in such a way that these can be identified from dynamometer measurements only.Secondly, in order to obtain the diagram of work, base on the hydraulic excitation system of the active suspension test-rig, the shock absorber test-rig has been built and the measurement system has been developed based on Labview.Thirdly, the genetic algorithm has been used to identify the parameters of model. Once identified, the model can predict well the behaviour of the damper for the wide range of signals tested.Finally, the model is validated by the comparison of the computer simulation results with the experimental results, it's shown that the simulation model is of considerable accuracy,and the model can be used in vehicle dynamics simulation and the study of control algorithms of semi-active damper.