Fig. 1. Model of gear structure. (a) Assembly relationship; (b) input shaft model; (c) output shaft model

Fig. 2. Assembly process of gear structure

Fig. 3. Flow of proposed method

Fig. 4. SUSAN circular template with 56 pixels in neighborhood

Fig. 5. Extraction results of tooth apex angle of output shaft and input shaft. (a) Tooth apex angle of input shaft; (b) tooth apex angle of output shaft

Fig. 6. Test results of auxiliary circle discrete arc segment of output and input shaft

Fig. 7. Midpoint extraction results of output shaft spline and input shaft missing tooth. (a) midpoint of spline; (b) midpoint of missing tooth

Fig. 8. Ellipse fitting results. (a) Fitting ellipse with tooth top circle and auxiliary circle of input shaft; (b) fitting ellipse with tooth top circle and auxiliary circle of output shaft

Fig. 9. Definition of spatial circular pose

Fig. 10. Position and pose measurement principle of spatial circular monocular vision

Fig. 11. Structure diagram of gear structure simulation assembly system

Fig. 12. Assembly diagram. (a) Alignment of component axes; (b) angle between spline and groove

Fig. 13. Experimental site