磁流变悬架汽车的非线性振动特性分析

研究了具有磁流变阻尼器悬架系统汽车的非线性动力学行为.汽车采用七自由度模型,磁流变阻尼器采用Sigmoid模型,路面激励为四轮有不同相位差的正弦激励.根据第二类Lagrange方程建立了汽车振动微分方程,采用四阶Runge-Kutta法进行数值仿真.以激励频率为参数分析汽车振动响应分岔过程,并通过时间历程图、相位图等分析了汽车在不同频率范围的振动特性,结果表明在特定的激励频率区间汽车发生混沌运动.分析结果可为基于磁流变阻尼器的车身振动控制提供理论指导.

Nonlinear vibration analysis of automobile with suspension system of magnetorheological damper

The nonlinear dynamic behavior of seven degrees-of-freedom （DOF） automobile with suspension sys- tem of magnetorheological damper is analyzed. Sigmoid model is used as damper model, and external stimulus are sinusoidal with phase difference. The bifurcation of motion versus the stimuli frequency is investigated . The non- linear dynamic behaviors are characterized by the time series of vibration response, phase diagram, Poincare map and power spectrum. The numerical results show that chaotic motion occurs at some special frequencies. The conclusions set some guidelines for the control of automobile with Suspension System of Magnetorheological Damper.