Abstract: In order to study the running stability problem of straddle type monorail, the straddle type monorail line in Chongqing was taken as the research object to establish the multibody dynamic model of 15-degrees-of-freedom, in which the PC track girder was regarded as rigid body and the non-linear characteristic of the rubber tire was considered. The dynamic differential equation of vehicle running was derived from Lagrange principle. Based on the simulation of PC track beam pavement in the American six road spectrum, the running stability of the straddle type monorail vehicle with different speed and variable radius of curvature was simulated and analyzed. The results show that in the small radius of curvature during the driving, the running stability of the vehicle decreases with the increase of the vehicle speed and increases with the increase of the radius of curvature.

Key words: vehicle engineering, straddle-type monorail vehicle, cornering characteristic, tire model, stability analysis

摘要： 针对跨座式单轨车辆运行稳定性问题，以重庆跨座式单轨交通车辆为研究对象，将PC轨道梁视为刚体，考虑橡胶轮胎的非线性特性，建立单轨车辆15自由度多体动力学模型，并运用拉格朗日原理推导出车辆运行时的动力学微分方程。采用美国六级路面谱模拟PC轨道梁路面激励，对跨座式单轨车辆在定曲率半径不同车速及变曲率半径不同车速工况下的运行平稳性进行了仿真分析，结果表明在小曲率半径曲线段行驶时，车辆运行平稳性随车速的增加而降低，随曲率半径的增加而提高。

关键词: 车辆工程, 跨座式单轨车辆, 侧偏特性, 轮胎模型, 平稳性分析