基于线激光的空间曲面轮廓非接触测量是目前工业产品在线尺寸精确检测应用的有效方法。为了提高非接触三角测量系统的精度, 需要准确表达被测轮廓的截面特征线。针对凹凸不平的被测工业零件表面, 采用单一光滑处理的拟合算法很难精确表达截面轮廓特征, 因此提出了以曲面轮廓特征点为边界点进行分段的多项式曲线拟合, 然后再进行叠加来产生一条连续轮廓曲线的方法。通过比较采集的被测物体数据点集与拟合产生的对应曲线可知, 所提方法不仅可以有效消除线激光提取过程中产生的锯齿问题, 提高了测量精度, 而且该拟合曲线能够真实地表达被测表面的轮廓特征, 具有重要的实际应用价值。

The non-contact measurement of space surface profile based on line laser is an effective method for the accurate on-line dimension detection of present industrial parts. In order to improve the non-contact triangulation accuracy, we need extract the section characteristic line of measured contour accurately. However, for the surface of industrial parts with irregular surface, it is difficult to express the contour feature accurately with a simple smoothing processing method. Therefore, a polynomial curve fitting method is proposed, which takes the contour feature points as the boundary points and then puts all the points together to produce a continuous contour curve. By comparing the collected data set of tested objects and corresponding fitted curves, we find that the proposed method can not only solve the jagged problem generated in the laser line extraction process, but also can improve the measurement accuracy. The fitted curve can truly express contour features of tested surface, which has important practical value.