Fig. 1. Contour Scanning Schematic

Fig. 2. Relationship between the center of the sphere and the cross-section circle

Fig. 3. Schematic of a set of data collectting

Fig. 4. Overall diagram of experimental equipment

Fig. 5. Profilometer collects calibration sphere contour data

Fig. 6. Standard deviation of spherical center coordinates

Fig. 7. Contour point cloud data and its fitted sphere