摘要
针对双短圆弧的准确检测难题,首先从工件的几何功能使用要求出发,详细分析使用三坐标测量机检测双短圆弧时误差产生的原因与影响;然后根据误差产生的原因,提出基于几何功能约束最小二乘拟合的双短圆弧检测方法。该方法将双短圆弧的设计半径、相对位置关系以及圆弧整体轮廓与工作基准的位置作为最小二乘圆拟合的约束条件,以降低拟合的误差。将该检测方法与经典最小二乘圆弧分段拟合检测方法进行对比实验,结果表明:提出的方法能够很好地改善最小二乘法对双短圆弧的拟合质量,有效降低检测结果的"误判"风险,可为双短圆弧的精确检测提供一种可靠方法。
The accurate measurement of double short arcs is a difficult task. A detailed analysis about the causes of errors in double short arcs measurements with CMM was performed in this paper, and a measuring method for double short arcs based on least square method with geometric usage constraint was proposed. In order to reduce errors and the influence of fitting, the method took the radii, the relative positions of arcs and the relative location between the overall contour of arcs and the working datum plane as constraint conditions. An experiment was conducted in comparison with traditional method, which simply applying classical least squares fitting on segmentation arcs. The results demonstrated that the proposed method could effectively improve the fitting quality of least square method on double short arcs, reduce the risk of ＂misjudgment＂ and provide a reliable way for the precise measurement of double short arcs.
出处
《中国测试》
CAS
北大核心
2016年第9期36-40,45,共6页
China Measurement & Test
基金
中国物理研究院计量测试中心发展课题(JCFZ2014-02)
