逆向工程中NURBS曲面重构技术研究

该文提出一种利用数据点特征的非均匀有理B样条(NURBS)曲面重构方法。针对三坐标测量机测得数据点的特点，自动建立散乱点的拓扑信息，简化繁琐的数据前期处理工作。在曲面重构方法上，采用NURBS曲面插值方法，针对数据点的分布不均匀性，通过累积弦长法构造非均匀节点矢量，保证曲面的插值精度。B样条求值的快速算法，利用，临时多项式替代递归调用，能提高运算效率。

NURBS Surface Reconstruction in Reverse Engineering

A procedure is proposed that reconstructs Non uniform Rational B Spline (NURBS) surface with features of measured data. With characteristics of measured points taken into consideration, topology information can be automatically extracted and it simplifies previous data process. The method of NURBS surface interpolation is applied for reconstruction. With non uniform data points, a method of accumulating chord length is presented to create non uniform knots vector and guarantees the precision of the surface. An optimal algorithm for B spline evaluation substitutes temporary polynomial expressions for the iterative application and enhances the computing efficiency.