Abstract:In order to better use the magnetorheological damper in the semi-active vibration control of magnetorheological damper coupling system, an accurate dynamic model of magnetorheological damper need to be established. Existing polynomial model of magnetorheological damper can fit the damping force-velocity curve accurately, but high-order polynomial fitting will lead to Runge phenomenon and violently oscillation at both ends of the fitting curve. To eliminate the Runge phenomenon, a piecewise cubic polynomial model is proposed in this paper and its parameters are identified by least square method. Compared with the experimental data, the piecewise cubic polynomial model can fit the damping force-velocity moer accurately and eliminate the Runge phenomenon.