基于半径差约束最小二乘拟合的短圆弧测量

Measurement of Short Arc Based on Difference of Radius Constraint Least Square Circle Fitting

测量短圆弧时,由于特征点较少,噪声干扰大,通常使用的最小二乘法很难满足测量要求。本文以大齿轮为研究对象,在最小二乘法拟合的基础上,提出了半径差约束的最小二乘拟合法。该方法先计算出大齿轮上一贴片点的半径,再利用半径约束的最小二乘圆拟合法计算出大齿轮的中心,最后运用程序对模拟数据和实例数据进行处理,证明利用该方法能够有效提高拟合精度。

In the process of short arc measurement,the least-square method is difficult to offer a high precision due to the lack of feature points and the influence of noise jamming.This paper takes large gear as the research object.On the basis of the least square method fitting,proposed the radius difference constraint least square fitting method.Firstly calculates the radius of a patch point on the large gear,then the center of the large gear is fitted with the radius constraint least square circle fitting method.The applications of simulation data and real data processing,prove that using this method can effectively improve the accuracy of circle fitting.