半径约束最小二乘圆拟合方法及其误差分析

Radius Constraint Least-square Circle Fitting Method and Error Analysis

针对基于线结构光视觉检测类圆工件三维测量中的光条圆弧特征数据所占整圆比例偏小,提出了基于半径约束最小二乘圆拟合方法。详细地分析了样本特征数据噪声对圆心定位精度的影响,并进行了仿真实验。实验结果表明,在光条圆弧特征数据所占整圆比例偏小的条件下,半径约束最小二乘圆拟合方法可以有效地提高圆中心定位精度。

In the process of 3-D measurement tured light vision sensor, feature data of the of the workpiece in shape of arc with strucstructured light arc is inadequate compared with the whole circle, which results in the location of the circle centre being of low precision. Least-squares method based on radius constraint is proposed in the paper to solve the problem. Influence of the noise in sample data the on the locating of circle centre is analyzed in detail, and simulated experiments are implemented. Results of experiments show that under the circumstances that feature data of the structured light arc is inadequate compared with the whole circle, the method proposed above can improve the accuracy of circle fitting efficiently.