1. Tomelleri S.r.l. ® Copyright 2007 © ASTRONOMY AND RESEARCH September 19th 2008 VST Meeting1

2. VST Project Primary Mirror Support System Progress Meeting Villafranca, September 19th, 2008 2September 19th 2008 VST Meeting

3. All Design Descriptions and Test Procedures related to the Axial Force Actuators, the Axial Fixed Points, the Astatic Levers and the Lateral Fixed Points, have been delivered also including the Final Design of Safety Devices foreseen to accept both the Teflon with springs and the Elastomer solutions, even though their stiffness and stroke need to be defined as a result of the earthquake analysis. The documents related to Harness will be completed with the As Built after completion of the accommodation of cables into the mirror cell foreseen within September 26. 36 Axial Force Actuators of the second and third rings have been integrated into the mirror cell while all remaining axial actuators have been tested and will be integrated within end September. The assembling and testing of the Axial Fixed Points will be ready before firmware delivery foreseen within end September. The Lateral Fixed Points have been assembled and tested and are ready to be integrated in the mirror cell. The Astatic Levers have been assembled and are being tested and therefore will be ready for the integration. Mirror Cell and the Dummy have been tested, and are positioned under the crane. All procedures for integration and testing of the Support System have been prepared and will be released after approval. September 19th 2008 VST Meeting3 PROGRESS SUMMARY

4. AXIAL FORCE ACTUATORS September 19th 2008 VST Meeting4 81 Axial Force Actuators have been tested and they all satisfy the requirements and particularly: - Maximum force range up 400 N can be obtained also when the sphere starts at a distance 1.6 mm from the mirror pad - Accuracy is better than 0.3 N with step 1 N. - Passive stroke is at least 3.2 mm when the actuator supplies 400 N, and the force is in any case less than 1500 N - Maximum force rate more than 20N/sec - Axial stiffness 200 N/mm - Maximum current < 0.1 A (nominal value 0.95A) Each actuator is certificated every 0.5 mm with the proper force- displacement diagram. 36 actuators have been integrated into the mirror cell while the remaining are ready for integration.

5. Axial Force Actuator on the test bench September 19th 2008 VST Meeting5

6. 6 36 Axial Force Actuators on the Mirror Cell

7. September 19th 2008 VST Meeting7 Axial Force Actuators before integration

8. The prototype of the Axial Fixed Point has been assembled and tested on the appropriate test bench, and it has satisfied the requirements and particularly: - Stiffness is 13300 N/mm more than 9000 N/mm - Passive stroke 3.2 mm with maximum load less than 1500 N - Preload between 580 N and 700 N Positioning accuracy has not been measured because the related software is not yet available but it has been verified that the two LVDTs measure the axial position with the required accuracy. The firmware to test positioning will be ready within end September. After this all remaining test will be done. September 19th 2008 VST Meeting8 AXIAL FIXED POINTS

9. Three Axial Fixed Points during assembling 9September 19th 2008 VST Meeting

10. All Astatic Levers has been assembled and now are being tested. The tested Astatic Levers satisfy the requirements and particularly: - Force accuracy better than + 5 N - Force adjusting range over 50 N - Accessibility for adjusting and mounting All 24 Astatic Levers will be integrated into the mirror cell within end September. Tests to verify the accessibility to mount and adjust the Astatic Levers, have been foreseen to perform after the mounting in the mirror cell. September 19th 2008 VST Meetin10 ASTATIC LEVERS

11. September 19th 2008 VST Meeting11 Astatic Lever on the Test Bench

12. September 19th 2008 VST Meeting12 Astatic levers after assembling

13. The four Lateral Fixed Points, included spare, have been assembled and tested on the appropriate test bench. Performance achieved: - Preload between from 600 up 800 N in both directions - Stiffness 25000 N/mm (requirement > 20000 N/mm) - Passive stroke 5 mm in all directions - Maximum force on the mirror is 1300 N The three Axial Fixee Points are now ready to be integrated into the mirror cell within end September. September 19th 2008 VST Meeting13 LATERAL FIXED POINTS

14. September 19th 2008 VST Meeting14 Lateral Fixed Points after assembling and testing

15. The system integration and test activities of M1 cell is being carried out at our facilities in our workshop. A crane, 3 ton capacity and 4 m radial stroke, equipped with non standard gearboxes to have a velocity of 1 m/min, has been installed. The handling of dummy is foreseen to be done by three adjustable tie rods and moved by the Hydra-set. The supports for the rotation system have been prepared to accept the drive system. September 19th 2008 VST Meeting15 INTEGRATION AREA

16. September 19th 2008 VST Meeting16 Mirror cell and Dummy under the crane

17. September 19th 2008 VST Meeting17 Handling for Dummy before Hydra-Set supply

18. September 19th 2008 VST Meetin18 Rotating support modified for the drive system

19. Testing of accuracy of the mirror cell: measures have shown astatic levers interface, M8 holes and derotator interface are within + 0.1 mm, while the interfaces to actuators have been corrected by the flanges height Adjusting and testing of the axial actuators interface within + 0.1mm, and the height of the sphere of the 36 actuators is within + 0.1 mm Testing of the dummy: on the first and second ring the height is within 0.1 mm, on the third and fourth ring 0.2 mm; lateral pads within 0.2 mm. Reworking of the mirror cell. Threaded holes to apply the lateral fixed points, safety devices and absolute transducers will be referred to the exixting threaded holes, and will be done (within end Sept. ) The pads under the dummy will be applied (within end Sept. ) Completion of the axial actuators integration and height verification (end Sept.) Lateral fixed points integration (within end Sept. ) Astatic levers integration(within end Sept. ) Absolute transducers integration(within end Sept. ) Integration of dummy in the mirror cell foreseen to be done at 10 October Safety devices will be integrated within November 8 with Teflon pads September 19th 2008 VST Meeting19 Integration Procedures

20. Mirror cell testing September 19th 2008 VST Meeting20

21. Dummy testing September 19th 2008 VST Meeting21

22. Flange height verification September 19th 2008 VST Meeting22

23. Integration of some axial actuators September 19th 2008 VST Meeting23

24. Height of the actuators September 19th 2008 VST Meeting24

25. Testing of the height of the Axial Force Actuators September 19th 2008 VST Meeting25

26. The diagrams of the harness have been completed, while the as-built drawings will be prepared within September 26. All power connection to the actuators have been done with the proper accommodation under the mirror cell, while the Can Bus will be connected within September 26. Distribution boxes and the repeater box have been fixed to the mirror cell ready for connection. September 19th 2008 VST Meeting26 HARNESS

27. Testing of axial actuators connected September 19th 2008 VST Meeting27

28. September 19th 2008 VST Meeting28 Power cables to connect to all axial actuators

29. The design of the mechanical supports of the safety devices have been completed and they foresee to accept both Teflon pads with springs and Elastomer pads. The safety devices include: - 16 upper axial safety devices - 14 lower safety devices - 18 lateral safety devices - 2 special lateral safety devices, in the East and West positions, that can be moved away from an accessible location. In order to get the safety devices ready for mirror demounting it is enough to rotate the upper part of the safety devices and bring the supports back ca 10 mm, so to avoid any interference with the mirror and with the handling. Four safety devices need to be demounted. Repositioning doesn’t require any backlash adjusting. September 19th 2008 VST Meeting29 SAFETY DEVICES

30. September 19th 2008 VST Meeting30 Safety devices general view

31. Safety devices general assembly September 19th 2008 VST Meeting31

32. Safety device in East-West positions September 19th 2008 VST Meeting32

33. Safety device lateral view September 19th 2008 VST Meeting33

34. Teflon pads with springs: - Shorter delivery time - Lower cost Elastomer pads: - Better pressure distribution - More damping - Smaller encumbrances We have had a meeting at Exsto facilities in France in order to answer all questions. All requirements seem to be satisfied, that will be confirmed in written form: stability, amount of permanent deformation, linear behaviour, two different kinds of elastomer. With the Elastomer solution the test on the mirror cell on the rotation system will be done with Teflon pads without springs. The elastomer pads will be tested in our facility before sending them to Paranal. September 19th 2008 VST Meeting34 Teflon-spring pads vs. Elastomer

35. September 19th 2008 VST Meeting35 Eladip applications

36. June 5th 2008 VST Meeting36 Eladip stiffness

37. TEST PROCEDURES AFTER INTEGRATION Test Procedures phase 1.A September 19th 2008 VST Meeting37 Integration Test Phase 1-A: tests at ground with the M1 Mirror Cell that lays horizontally on the four supports and before Dummy Integration T1. Geometry of the Axial Actuators (both Axial Force Actuators and Axial Fixed Points) T2. Reading of the Absolute Transducers T3. Software-Hardware Communication T4. Axial Actuator Manual Control System Detailed procedures are available in the proper document

38. Test Procedures phase 1.B September 19th 2008 VST Meeting38 Integration Test Phase 1-B: tests at ground with the M1 Mirror Cell that lays horizontally on the four supports and after Dummy Integration T5. Geometry Test of the Lateral Fixed Points T6. Geometry Test of the Astatic Levers T7. Radial Dummy stroke T8. Load Control of the Axial Force Actuators T9. Accessibility to all devices for Maintenance Detailed procedures are available in the proper document