说明：  迹线法实现轮轨接触，是轮轨接触力及垂向力的基础内容，需要轮轨接触角及型面数据作为初始 内容
(Trace method to achieve the wheel-rail contact, is wheel-rail contact force and the vertical force base, you need a wheel-rail contact angle and surface data as the initial content type)