Data Transformation for the Optimal Projection Direction of Mesh Surface

In the 5-axis NC machining, the
$3+2$
axis machining is one of the most commonly used methods, which requires the two rotation axes are fixed with the direction of the most projected area. The parameter surface model can directly obtain the overall external vector of the surface model as the direction to fix the two rotation axes and transform the model data to achieve the 3-axis linkage machining according to this direction. However, the mesh surface only provides the information of all the facets in the model data, there is not direct data for driving two rotation axes orientations, and there is a lack of corresponding method to convert model data for the 3-axis machining. This paper proposes a data transformation method to generate the optimal projection direction for the mesh surface and realize the data transformation for the 3-axis machining in this direction. Through the computer programming, a simple system is developed and this proposed method is verified. The experimental results prove that the calculated optimal projection direction and the transformed model data can provide effective basic data for the
$3+2$
axis mesh surface machining.