前轮自激摆振分岔特性研究

根据非线性理论研究了某非独立悬架汽车前轮自激摆振的分岔特性.利用非线性系统Hopf分岔发生的条件编制计算自激摆振分岔车速的MATLAB程序,绘制了不同转向结构参数、轮胎结构参数以及前轮定位参数对应的右车轮摆角幅值随车速变化的分岔图,分析了各参数对自激摆振的影响.结果表明,某些参数变化导致自激摆振发生时最大振幅所对应的车速改变;转向机构刚度、轮胎侧偏刚度和拖距对自激摆振的幅值影响较大.

Study on the Bifurcation Characteristics of Front Wheel Self excited Shimmy

According to the non linear theory, the bifurcation characteristics of front wheel self excited shimmy of some motor vehicle with non independent suspension were studied. Computer programs were carried out to calculate the range of self excited shimmy speed of the motor vehicle with MATLAB when Hopf bifurcation took place. Various bifurcation diagrams indicating the relationship between angle amplitudes of right tire and vehicle speed were presented. And the influences of different parameters on self excited shimmy were analyzed. Numerical simulation results have indicated that the increase and decrease of the structural parameters of steering mechanism and tire parameters can restrain the self excited shimmy. With the change of some parameters, the vehicle speeds relating to the tire maximum angle amplitude of the self excited shimmy change correspondingly. The steering stiffness, tire cornering stiffness and pneumatic trail show greater impact on the amplitude of self excited shimmy.