一种用NURBS表示的过渡曲面的生成方法

讨论在两参数曲面上生成显式定义的参数过渡曲面问题。提出了一种围绕两曲面的交线,采用参数化平面与曲面之一的等距面求交,寻找两曲面的等距点,以产生变半径过渡曲面的方法;过渡曲面本身为2次×3次NURBS曲面,充分利用了NURBS曲线可精确表示圆弧曲线的特点,并使得可用统一的算法对过渡曲面进行各种处理。

A VARIABLE RADIUS BLENDING SURFACE MODELING METHOD

This paper discusses the problem of constructing a NURBS defined blending surface on two NURBS surfaces. A method for finding offset point around intersection curve between two surfaces is proposed. The method has the advantage over the traditional approach in that the offset point can be found more quickly and accurately. Any rectangular parametric surfaces can be blended as long as their offset surfaces are smooth so that intersection between a parametrically defined plane and one of surface offset can be well defined. The blending surface itself is expressed as a 2x 3 NURBS surface, which not only makes it more accurate and its fullness can be easily controlled, but also makes it possible for our system to adopt a unified way to process the surface.