一种利用坐标测量机实现圆度误差评价的方法

Roundness error evaluation algorithm using coordinate measuring machine

针对直角坐标系下圆周截面形状误差评价,介绍了一种圆柱体截面圆度误差的测量与评定方法。在研究了圆度误差定义及测量方法的基础上,建立了基于三坐标测量机的最小外接圆圆度误差三维评测模型。利用双截面最小二乘拟合轴线调整坐标系位置,减少了位姿误差对测量结果的影响。对模型进行坐标系统一转换,使得变换后的模型能更适用于计算机数据处理。然后在坐标变换的前提下,提出了一种利用几何关系搜索最小外接圆圆心的方法,开发了相应的数据分析软件。实验和数据证明,此算法优于传统最小外接圆算法,实现了在直角坐标系下三坐标测量机对圆度误差的最小外接圆法评价。

Aiming at circumferential form error evaluation in cartesian coordinates, this paper highlights the application in measuring and evaluating form errors, especially the roundness error of cylindrical sections. On the basis of compre-hensive study about the definition and measurement method of roundness error, the 3D measurement and evaluation model of minimum circumscribed circle（MCC） based on three coordinate measuring machine （CMM） is established. A double-section method for adjusting coordinate position using least-square axis is applied to reduce the effect of the model pose error on measurement result. Different coordinate systems of the model are transformed to the same system through transition matrix, so the new model is more suitable to computer data processing. Then, with coordinate transformation, a new algorithm is proposed, which uses geometrical relationship to search the minimum circumscribed circle center, and corresponding analytical software is also developed. Experimental data prove that the algorithm is superior to traditional method in realizing MCC roundness error evaluation in Cartesian coordinate system using CMM.