基于复合三角Bezier曲面/平面交线的裁剪

Trimmng Based on Composite Triangular Bezier Surface/Plane Intersection

提出一种复合三角Ｂｅｚｉｅｒ曲面与平面的求交算法，这种算法能处理多条交线、交线环的情况，在自由曲面数控加工编程中具有广泛的应用场合，对提高汽车等领域的自由曲面ＮＣ加工精度具有重要的工程价值。将交点作为型值点插入相应的三角网格，通过三角网格的重新划分和分离，实现复合曲面的裁剪。试用显示，这种裁剪方法在工程上是行之有效的。

A new algorithm for the intersection curves between composite triangular Bezier surface and a plane is presented. The method can solve not only many curves but also intersection loops.It is proved that this method is widely applicable in NC automatic programming and is significant to improve the precision of NC machining for patametric surface of automobile. By inserting the intersection points into relevent triangular grids as measuring points, retriangulating and splitting of triangular grids,the surface can be trimmed.Experiments show that this method can be used in engineering practice.