自适应迭代区域搜索法用于直线度的精密评定

. An Adaptive Area Search Method for Straightness Precision Evaluation

为实现直线度误差的精密评定,提出自适应迭代区域搜索方法。首先对测量采样数据以第一测量点为原点进行坐标平移预处理,然后计算各测量点与原点连线的斜率分布区间,以此作为初始搜索区间。根据设置的每代候选基准数计算初始搜索步长,以初始搜索区间中线为搜索起始基准线开始搜索计算,可得到当代最小直线度误差对应的评定基准直线,并以其为新一代搜索计算的起始搜索基准线,以新、旧起始基准直线的斜率确定新的搜索区间和搜索步长,以新的起始基准直线开始搜索新一代最小直线度误差对应的基准线,反复迭代计算至终止条件。对两组实例进行了计算。实例验算证明迭代区域搜索方法原理正确、精度较高、运算速度快、简单易于实现。

In order to precisely evaluate the straightness error,an adaptive strategy is proposed to locate the datum line based on basic area search approach. First,the sampled measured dataset was translated with the first measured point as the new origin. Secondly,the slopes of the lines between the origin （first point） and other points were computed. The range of the slopes was used as the initial search area and the initial start line was its middle line; the initial search step was computed together with the appointed number of candidate lines and some candidate datum lines were given. Thirdly,the straightness errors can be worked out which conform to the minimum zone condition for each candidate datum lines and the one with minimum straightness error was selected and used as the new start line of the next search. The new search area was the area between the new and old datum lines and the new search step was computed with it. The above computation continues until the terminal condition is met. Two groups of examples were computed. The computation results show that the proposed method is correct,precise,efficient and easy to realize.