磁流变减振器滞环特性试验及建模方法

由于磁流变减振器数学模型滞环特性描述通常不能兼顾简洁、精确，而限制其实际工程应用，因此，设计用于数学模型，参数辨识和验证的几组不同的连续变化的激励振幅、频率和电流强度，并应用实物磁流变减振器进行动态特性测试。根据测试结果分析无电流输入以及激励位移、速度和电流强度变化时，磁流变减振器的弹性、阻尼、电流饱和等基本特征的动态非线性特性。依据试验分析结合非线性粘塑性模型和简单非线性Bingham模型，提出应用神经网络理论中神经元S型传递函数，实现减振器活塞运动方向发生变化时力―速度特性模型中阻尼力的平滑过渡；同时借鉴非线性滞环双粘性模型以活塞加速度方向的变化，判断压缩屈服和拉伸屈服两个不同过程的方法，建立描述磁流变减振器滞环特性的数学模型。进一步分析所建模型中可控阻尼力部分各个参数的物理意义。通过试验数据对S型滞环特性数学模型进行参数辨识，并重点分析速度―力特性曲线所形成滞环的斜率及宽度相关参数的可控特性，最后以试验数据验证S型滞环模型的正确性。

EXPERIMENT AND MODELING RESEARCH ON HYSTERETIC LOOP OF MAGNETORHEOLOGICAL DAMPER

Because the mathematical model of magneto- rheological damper(MRD)isn't simple and accurate enough to reflect dynamic hysteretic behavior for engineering application, according to diverse actuating amplitude,frequency,current,a MRD prototype is tested for parameter identification and veri- fication.Based on the test data the nonlinear dynamic behavior of MRD elastic,damping and current saturation characteristic is analyzed by variable actuating displacement,velocity and cur- rent when MRD is controlled with current or without current, To make the force-velocity curve smooth when the direction changes,neural network sigmoid transfer function is utilized integrating the test investigation,nonlinear viscosity-plastic model and simple nonlinear Bingham model.Also,the com- press and extension process is distinguished according to the accelerator direction as the nonliear bi-viscosity model.Based on mentions above the hysteretic behavior model of MRD is established.Then the physical meanings of several parameters for controllable damping force in model are studied.After iden- tifying the parameters in sigmoid hysteretic model,the control- lability of the parameters which affects the force-velocity hys- teretic loop slope and width is researched especially.The sig- moid hysteretic model is verified by experimental data finally.