And they are often distorted. First, a low passed filter is used to smooth the contour. And a polygon approximating method based on area error is used to approximate the contour.
The paper develops general interpolation principals for parametric curves with constant feedrate, and contour error's approximate evaluations are discussed also.
阐述了参数曲线恒速插补的通用原理，同时讨论了轮廓误差近似计算方法。
3
At the same time, how to get the approximate road hollow position is solved to realize the road contour extraction by gradient vector flow model with iterative solution.