曲率计算公式的改进及应用效果

曲率属性近年来在构造识别和解释上得到了迅速的发展和应用，而曲率计算通常使用3×3网格单元对局部曲面作最小二乘法逼近，由Roberts推导并给出了具体的计算公式，该方法在求取曲率值时带来了大量噪声。采用5×5网格单元对局部曲面进行最小二乘法拟合，导出了5×5网格单元求取曲率的计算公式，并对3×3网格、5×5跳点网格、5×5网格求取曲率的结果进行了对比。结果表明，改进后的曲率计算方法抗噪能力显著增强。 

New curvature calculation formula and its application

The previous researches calculated the curvature by using the least square method to approximate the local surface with 3×3 grid. Its specific calculation formula is deduced by Roberts. The aperture brings a lot of noise when we calculate the value of the curvature. In order to solve this problem, we use the least square method to approximate the local surface with 5×5 grid, give the detailed calculation formula and then compare with the results got by 3×3 grid, 5×5 jumping grid and 5×5 grid. The results prove that the improved curveture methods has enhanced the anti-noise ability.