Abstract:

Based on blending surface method by combination functions,a new algorithm of designing G1 continuous curve on the base surface was proposed. Given an arbitrary sequence of points and the tangent directions of the points,a space curve can be designed. By using the normal projection method,the curve was projected orthogonally onto the base surface
and thus the blending contact curve  was obtained. In this way, the contact curve can be placed at the appropriate position according to the design requirements as the borderline of the blending surface. The new methods were presented to generate auxiliary surface and reparameterize local base surface, which extended the capability of the blending method. The effectiveness and feasibility of the new algorithm were illustrated with an instance of blending wing body.

Key words: transition surface, blending function, contact curve, auxiliary surface

摘要：

在采用组合函数法构造过渡曲面方法的基础上,提出了一种在基曲面上构造G1连续的过渡切触线的方法。该方法只需给定曲面上的一组点列及其点上的切矢,在此基础上构造一条空间曲线,并基于正交投影法将这条曲线投影到基曲面上得到一条G1连续的过渡切触线，使得设计人员可以根据需要直接在基曲面上确定过渡曲面与基曲面的切触线的位置，并以此为边界构造过渡曲面。还提出了新的构造过渡辅助面和重新参数化局部基曲面的方法,以适应过渡切触线为分段曲线的情况，并将其应用于翼身融合面的构造中，实例证明了该方法的可行性,效果令人满意。

关键词: 过渡曲面, 过渡组合函数, 接触线, 辅助面