# Algorithm for Tool Path Offsetting Based on NURBS Surface

## 摘要:

This paper presents an algorithm for tool path offsetting based on NURBS surface. First the progenitor free surface is fitted with a bi-cubic NURBS surface and the unit normal vectors of the NURBS surface is computed precisely, then the offset surface can be obtained by offsetting the NURBS surface in the normal vector direction with the required distance. Considerable extra computational time can be saved, especially when they are to be offset by several times. As the method successfully computes the unit normal vector of the progenitors, the offset error of this method is zero. The method can also be generalized to other degree NURBS surface, and it can improve the machining accuracy of the surface.

## 信息:

Jingtao Han, Zhengyi Jiang and Xianghua Liu

111-114

Y. Yue, "Algorithm for Tool Path Offsetting Based on NURBS Surface", Advanced Materials Research, Vols. 945-949, pp. 111-114, 2014

June 2014

\$38.00

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