文摘:基于缓和曲线平行线弧长公式及其性质，给出了缓和曲线平行线以其自身弧长为变量的参数方程。

• Abstract: Based on the arc length formulae of the parallel to the easement curve and its property, this paper gives the parameter equations of the parallel to the easement curve takiing the arc length itself as variable.