基于双横臂的1/4汽车模型及其等效模型的建模控制研究

Modeling and control of a quarter-car model with doublewishbones and its equivalent two degrees of freedom model

建立了基于双横臂悬架的1/4汽车模型和等效的二自由度模型。根据基于双横臂悬架的1/4汽车模型的簧载质量和非簧载质量的动力学响应,通过参数辨识的方法,给出了辨识等效二自由度模型的质量、刚度和阻尼系数的方法。计算结果表明,等效二自由度模型辨识结果中的刚度和阻尼系数的数值与基于双横臂悬架的1/4汽车模型中相关参数的名义值有较大的差异。分析了悬架衬套、减振器上端支撑的刚度对等效二自由度模型参数辨识结果的影响。对比分析了采用辨识参数的等效二自由度模型和基于双横臂悬架的1/4汽车模型的簧载质量和非簧载质量的响应,证明了参数辨识方法的准确性。基于辨识参数的二自由度控制模型,给出了基于等效二自由度模型的参考模型滑模控制方法。试验和计算结果表明,与采用名义值相比,参考模型的刚度和阻尼系数采用辨识值时,等效二自由度控制模型可以获得更好的控制效果。

A quarter-car model with a double-wishbone suspension and its corresponding equivalent model which is a two degrees of freedom(2DOFs)system with damping were proposed.Based on the calculated dynamic responses of the quarter-car model with the double-wishbone suspension,the method for identifying the mass,stiffness and damping parameters of the 2DOFs model was developed.The dynamic responses of the 2DOFs model with different values of mass,stiffness and damping were calculated and compared,where one set of mass,stiffness and damping parameters is of nominal values and another set is of the identified values.The influences of the stiffnesses of the bushing and topmount of the suspension on the identified parameters were investigated.A sliding mode control algorithm based on a reference model with an equivalent 2DOFs model was proposed.The influences of the mass,stiffness and damping parameters in the 2DOFs model on the controlling effect was investigated to demonstrate the importance of the exactness of parameters.