Fig. 1. Control principle of POPM

Fig. 2. Control principle of POPM

Fig. 3. Description of five parts

Fig. 4. Description of five parts

Fig. 5. Design block diagram of current loop

Fig. 6. Control scheme of POPM on telescope

Fig. 7. Control system platform of POPM

Fig. 8. Position and velocity curve when 4 m telescope moved at 1 （°）/s

Fig. 9. POPM variation without control when 4 m telescope moved at 1 （°）/s

Fig. 10. LVDT error without control when 4 m telescope moved at 1 （°）/s

Fig. 11. POPM variation withcontrol when 4 m telescope moved at 1 （°）/s

Fig. 13. LVDT error without control when 4 m telescope moved at 1 （°）/s

Fig. 14. Elevation position and velocity curve when 1.2 m telescope elevation axis moved at variation speed and the primary mirror without control

Fig. 15. POPM when 1.2 m telescope elevation axis moved at variation speed and the primary mirror without control

Fig. 16. LVDT error when 1.2 m telescope elevation axis moved at variation speed and the primary mirror without control

Fig. 17. Elevation position and velocity curve when 1.2 m telescope elevation axis moved at variation speed and the primary mirror with control

Fig. 18. POPM when 1.2 m telescope elevation axis moved at variation speed and the primary mirror with control

Fig. 19. LVDT error when 1.2 m telescope elevation axis moved at variation speed and the primary mirror with control

Fig. 20. Anti-disturbance capability of POPM control