一种基于Partial EIV模型的圆曲线拟合解法

A Circular Curve Fitting Solution Based on Partial EIV Model

针对圆曲线拟合问题,以圆曲线的参数方程为基础建立圆曲线拟合的EIV模型,根据系数矩阵的特点将模型转化为更合理的Partial EIV模型,通过公式变形为最小二乘形式,采用两步迭代法求解模型参数,保证系数矩阵中相同元素的改正数一致,常数元素的改正数为零。算例数据结果表明,所提算法的可行性、拟合精度相对较优。

Aiming at the problem of circular curve fitting,based on the parametric equation of circular curve,firstly this paper establishes the EIV model of circular curve fitting,and transforms the model into a more reasonable Partial EIV model for the characteristics of the coefficient matrix.Then,the formula is transformed into the least squares form,and the two-step iterative method is used to solve parameters of the model,ensuring that the corrections of the same elements in the coefficient matrix are same,and the corrections of the constant elements equals zero.Finally,combing case data shows the feasibility of this algorithm,and fitting accuracy is relatively superior.