Abstract: A measuring method of simulating actual measuring tool processes was proposed to evaluate the line profile errors. The method followed the least condition principle of shape tolerances in the national standard. The position relationship between the measuring points and the corresponding envelope boundary was analyzed， the set of measurement points was regarded as a rigid body. The relative motions were calculated between the rigid body and the boundary which might occur in the processes of the boundary shrinking to the minimum region， and finally all the measured points were located in the minimum containment region. The results show that evaluation processes are more global and directivity than  that of the large-scale search of common optimization algorithm， which may effectively avoid the local solutions of the search results caused by the algorithm defects. The proposed method is suitable for the error evaluation of line profiles.

Key words: line profile, least condition principle, error evaluation, virtual measurement

摘要： 提出一种模拟实际量具测量过程的方法来评定线轮廓度误差。该方法遵循国家标准中对形状公差的最小条件要求，通过分析测量点与对应包络边界的位置关系，将测量点集视为刚体，计算边界收缩至最小区域的过程中刚体与边界可能出现的相对运动，最终使所有测点位于最小包容区域内。结果表明：所提方法的评定过程相对于常用优化算法的大范围搜索更有全局性与单一性，可有效避免出现由算法缺陷导致搜索结果陷入局部解的情况。该方法适用于线轮廓度误差的评定。

关键词: 线轮廓度, 最小条件, 误差评定, 虚拟测量