关键词: 最短距离, 分割球面逼近, 轮廓度误差, 改进单纯形法

Abstract: A subdivision and sphere approximation method was presented in order to improve the accuracy and efficiency of the evaluation. First of all, the surface patch containing the perpendicular foot of measuring point was determined by subdividing the surface. A sphere, approximating the surface patch, was constructed with four points on the surface patch and the approximate distance was then obtained based on the geometric properties of sphere. Finally, the surface patch was subdivided and the above process was iterated until the difference between adjacent results was less than the preset threshold. The evaluating of complex surface profile error was realized by using subdivision and sphere approximation method combined with improved simplex method. The calculating examples showed that the subdivision and sphere approximation method was rapid and accurate, which was suitable for the evaluating of complex surface profile error.

Key words: shortest distance, subdivision and sphere approximation, profile error, improved simplex method