摘要
为使参数曲线拟合在压缩数据量的基础上仍能保持较高的精度,提出了一种基于特征点提取、最小二乘法逼近以及粒子群优化算法求解最优控制点的高精度非均匀有理B样条(NURBS)曲线拟合方法。首先,以反曲点和曲率极值点作为筛选依据从所有离散数据点中提取特征点;然后,将特征点在最小二乘法下逼近,并根据所得线性方程组计算得到初始控制点;最后,以初始控制点的位置坐标构造粒子初始种群,并建立一个衡量离散数据点与拟合曲线误差的适应度函数,且利用粒子群优化算法对初始控制点的位置进行迭代优化,直至达到最大迭代次数为止。在叶片和蝴蝶截面原型上进行的实验验证的结果表明,所提方法使待拟合数据量分别压缩为原来数据量的25/117和120/283,且与以精度高为优势的增加辅助控制点的方法相比,所提方法的拟合精度分别提高了57.1%和22.9%,在已有曲线拟合研究方法中具有较强竞争力。
In order to maintain high precision of parameter curve fitting on the basis of compressed data,a high-precision Non-uniform Rational B Spline(NURBS)curve fitting method was proposed based on feature point extraction,least square approximation and particle swarm optimization algorithm solving optimal control points.Firstly,feature points were extracted from all discrete data points based on the inflection point and curvature extreme points.Then,the characteristic points were approximated by the least square method,and the initial control points were calculated according to the obtained linear system of equations.Finally,the initial population of particles was constructed by the position coordinates of the initial control points,and a fitness function was established to measure the errors between the discrete data point and the fitting curve.The positions of the initial control points were iteratively optimized by the particle swarm optimization algorithm until the maximum number of iterations was reached.The results of experimental verification on blade and butterfly section prototypes show that the amount of data to be fitted is compressed to the 25/117 and 120/283 respectively of the original one by using the proposed method.Compared with the method of adding auxiliary control points with high accuracy as advantage,the proposed method has the fitting accuracy 57.1%and 22.9%higher,indicating strong competitiveness of the method in the existing curve fitting research methods.
作者
盖荣丽
高守传
李明霞
GAI Rongli;GAO Shouchuan;LI Mingxia(School of Information Engineering,Dalian University,Dalian Liaoning 116622,China;Shenyang Institute of Computing Technology,Chinese Academy of Sciences,Shenyang Liaoning 110168,China;University of Chinese Academy of Sciences,Beijing 100049,China;School of Information Science and Engineering,Dalian Polytechnic University,Dalian Liaoning 116034,China)
出处
《计算机应用》
CSCD
北大核心
2022年第7期2177-2183,共7页
journal of Computer Applications
基金
国家自然科学基金资助项目(61602074)
辽宁省自然科学基金指导计划项目(2019⁃ZD⁃0309)。
关键词
粒子群优化算法
最优控制点
最小二乘法
非均匀有理B样条曲线
反曲点
曲率极值点
particle swarm optimization algorithm
optimal control point
least square method
Non-Uniform Rational B Spline(NURBS)curve
inflection point
curvature extreme point
