Analysis and Modeling of Magnetorheological Hydro-pneumatic Spring Based on Bouc-Wen Model

In order to accurately describe the dynamic characteristics of magnetorheological hydro pneumatic spring, its working performance was tested, and a nonlinear model which can accurately describe its hysteresis characteristics was proposed based on Bouc-Wen model. Firstly, the mechanical properties of hydro pneumatic spring were tested, and its working characteristics were analyzed based on the test results. Secondly, the analysis of the output influence of each parameter in the Bouc Wen model is completed. The analysis results show that the nonlinear hysteretic system can be flexibly described by adjusting the parameters. Thirdly, based on Bouc-Wen model, a non-linear model of hydro pneumatic spring was proposed, and the target interval was narrowed by several iterations using genetic algorithm, thus the identification of model parameters was completed. Then, the relation function of each parameter in the model with current was obtained by ordinary least squares, and the non-linear model of hydro pneumatic spring was established. Finally, the numerical analysis of the magnetorheological hydro pneumatic spring nonlinear model was completed. The analysis results show that the calculation results of the hydro pneumatic nonlinear model agree well with the test results under the same input. The hydro pneumatic spring nonlinear model established can accurately describe its operating characteristics. This paper firstly applies Bouc-Wen model to the nonlinear modeling of new magnetorheological hydro-pneumatic springs, which provides a reference for the dynamic modeling of related magnetorheological hydro-pneumatic devices.