提出了一种最小环带的数学定义：作出的环带上存在至少二个内点与二个外点在圆周上呈交错排列。以此定义作为搜索结束的准则，给出了一种计算最小环带的数值算法：以交错排列的四点作环带，不断用新点取代旧点作环带直到所有的点都在环带内为止。最后给出了应用该方法测量机床主轴回转精度的工程实例。

A minimum ring-band mathematical definition :In the done ring-band, there are at least two inner points and two outer points which scatter staggeringly on the circumference. With this definition as the rule of searching calculation' s ending,a fast numerical algorithm of gaining the minimum ring-band of a closed curve was suggested:Make a ring-band with the four points scattered staggeringly,then replace the old points with new ones continuously until all the points are located within the ring-band. The method was used in an application example to measure the spindle rotating precision of machine tools.

TG502.13