一种最小区域球度误差评定算法

The Minimum Zone Sphericity Error Evaluating Based on Parabola Method

根据直角坐标系下的球度误差的几何定义,提出了一种最小区域球度误差评定算法。首先以最小二乘球心为初始参考点,以之为球心构建一个辅助球,用经纬法将球面分布辅助点,以这些点为假定理想球心计算所有测量点的半径值,再根据最小条件筛选出若干条由辅助点构成的直径,分别对这些直径使用抛物线法缩小搜索区间,最终获得最小区域法对应的参数。实例结果表明,该方法能准确地获得最小区域解。

According to the geometric definition of sphericity error in cartesinan coordinate system,the minimum zone sphericity error’s evaluating method based on parabola method was proposed.First of all,the center of least squares was used as the initial reference point,and a auxiliary ball was constructed for the ball center,and the auxiliary points of the spherical surface were used by the longitude and latitude method.The radius values of all the measured points were calculated by using each auxiliary point as the ideal center.Then,several diameters which constituted by auxiliary points were selected according to the minimum condition,and the parabolic method was used for these diameters respectively to reduces the search interval and finally the parameters corresponding to the minimum zone method were obtains.The example shows that the method can get the minimum zone solution accurately.