车辆随机振动稳定性分析

Stability analysis of the vehicle random vibration

以1/4车辆两自由度模型为研究对象,研究了线性与非线性悬架系统车辆行驶的稳定性.在线性悬架系统中,利用虚拟激励法推导出车辆加速度功率谱密度函数表达式,借助MATLAB仿真分析了当车辆各参数在一定范围内变化时车辆行驶的平顺性.当车辆悬架刚度、阻尼等分别作为随机参数,且参数服从正态分布时,利用四阶Runge-kutta数值方法,对非线性悬架系统的动力学行为进行了数值仿真.仿真结果表明,合适的悬架参数,可以有效控制车辆的振动,应当重视车辆线性与非线性悬架参数的选取.

By taking two degrees of freedom model of the 1/4 vehicles as the study object, per analyzes the vehicle stability in both linear and nonlinear suspension systems. In th suspension system, Pseudo Excitation Method is density function expression .of the vehicle. When certain range, MATLAB is used to simulate the the pa-inear adopted to derive acceleration power spectral parameters of the vehicle are changed within a riding comfort of the vehicle. In the nonlinear suspension system, when vehicle suspension stiffness and damping are respectively taken as ran- dom parameters and meanwhile these parameters follow the normal distribution, the numerical method of Fourth-order Runge-kutta is employed to simulate the dynamic behavior of the system. The above two simulations show that appropriate parameters of the suspension can effectively control the vibration of the vehicle and that attention should be paid to the selection of the param-eters of vehicle linear and nonlinear suspension.