Fig. 1. (a) Geometric model; (b) Grid division; (c) Load and boundary condition settings

Fig. 2. (a) Normal stress of screw cross-section (T=2000 N ·mm); (b) Comparison of theoretical and simulation results of pretension for screwed joints

Fig. 3. (a) Stress distribution; (b) The maximum stress change in the cross-section of the first contact screw tooth; (c) Change in pretension of screws; (d) Change in screw rotation angle

Fig. 4. (a) Schematic diagram of the composition of the mirror subassembly; (b) Contact geometric feature correction

Fig. 5. (a) Deformation cloud map of the mirror base; (b) Deformation cloud map of the mirror

Fig. 6. (a) Cloud map of mirror surface deformation when the pretension of the screws H, I, J, and K on the mirror base is reduced to 1000 N; (b) Cloud map of mirror surface deformation when the pretension of the screws B, C, D, E, F, and G for the mirror is reduced to 1000 N

Fig. 7. (a) Cloud map of mirror surface deformation when the installation screw J of the mirror base is completely loose; (b) Cloud map of mirror surface deformation when the installation screw B of the mirror is completely loose

Fig. 8. Experimental testing system

Fig. 9. Experimental test result

Fig. 10. Impact of screw type

Fig. 11. Impact of thread friction coefficient

Fig. 12. Impact of frictional resistance on support surface

Fig. 13. Equivalent simulation model for thread dispensing

Fig. 14. Impact of thread dispensing