3.2.4. Feature Extraction

The endpoint of the component must be extracted from the cross-section of the point cloud. If the cross-sectional information of a certain plane is directly obtained, it can readily result in insufficient information (Figure 3a). To resolve this, the method used in this research projects the segmented point cloud data to the minimum value of the reference direction according to the three axes (XYZ). The planarized point cloud has dense point clouds (Figure 3b).

**Figure 3.** (**a**) 3D point clouds are projected onto a certain section; point clouds are few. (**b**) Planarized point cloud from proposed method has dense point clouds.

An endpoint feature extraction process can then be performed. The planarization results in the three dimensions of XYZ are considered separately during the extraction operation. The coordinate values of components in three dimensions are extracted to achieve feature extraction.
