Fig. 1. Mathematical model of line structured light 3-D vision measurement

Fig. 2. Schematic diagram of rotating scan center axis calibration

Fig. 3. Algorithm flow chart of extracting laser stripe centerline in this paper

Fig. 4. Laser stripe centerline extraction algorithm in this paper. (a1), (a2) Gray-scale image of laser stripe on the welding seam of a metal hub; (b1), (b2) Preliminary gray centroid method to extract the centerline of laser stripe; (c1), (c2) Frame selection of missing segments; (d1), (d2) Adaptive gray-scale enhancement to repair missing segments; (e1), (e2) Gray centroid method to completely extract the centerline of laser stripe

Fig. 5. 3-D vision measurement scheme in this paper

Fig. 6. 3-D vision measurement steps based on line structured light rotation scanning

Fig. 7. (a) Physical drawing of measured metal hub; (b) Experimental diagram

Fig. 8. 3-D contour reconstruction renderings of the wheel hub

Fig. 9. Repeated measurement results of the maximum radius of the outer contour of the hub

Fig. 10. Repeatability error of the maximum radius of the outer contour of the hub

Table 1. Vision module calibration parameters

Table 2. Standard bat measurement results