在轨道上.列车的稳定性可溯源于车轮的圆锥形状，当有横向扰动时会产生法向回复力.我们首先考虑简单的情况，假设轨道

为无摩擦的并且忽略轮子的旋转.然后我们再建立一个更全面的模型，即全面考虑摩擦和旋转.我们证明了滚动摩擦使得旋转

运动与平移运动叠加，从而增强了整体稳定性.最后，我们找到获得稳定参数的近似公式，计算获得的结果与真实铁路客车的

参数非常一致.

perturbations that could cause it to derail.We show that train stability originatesfrom the conical shape of the

wheels，which gives rise to a restoring normal force in response to alateral disturbance.We first demonstrate translational

stabilization in a simple situation where therails are assumed frictionless and the steering motion of the wheel

is neglected.We then develop amore comprehensive model， taking friction and steering into account.We show that

rolling frictioncouples the rotational motion to the translational motion，enhancing overall stability.Finally，we find

approximate formulae for the parameters governing stability，and show good agreement withparameters of a real railway

coach.