Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas MOUNT DESIGN

1. Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas • MOUNT DESIGN • PM#06- 18-19 July 2006

2. Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas • BASE • PM#06 18-19 June 2006

3. Base design: • Optimization of the attachment to the foundation • Base design from conical to polygonal • New connection between base interface and foundation • Connections for skirt (preliminary- under discussion) • Bearing interface with pins (preliminary- under discussion)

4. vvvvccc • Optimization of the insert attachment to the base structure by means of two pins – one used for centering

5. Polygonal base structure

6. Skirt connections Floor layout and electrical cabinet position

7. Electrical cabinet lay-out - Section

8. AZIMUTH BEARING INTERFACE AND SUPPORT SKIRT ARRANGEMENT • Improved internal side of the bearing interface in order to permit easy clean up of the old grease during lubrication; • Optimization of the skirt and support skirt arrangements;

9. Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas • AZIMUTH BEARING • PM#06 18-19 June 2006

10. Optimization of azimuth bearing: New drawing with encoder On going: seals definition On going: fixing screws number

12. Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas • ELEVATION SADDLE • PM#06 18-19 June 2006

13. DEVELOPED ACTIVITY • Optimization of the lateral struts using two C profile; • Substitution of the Radial Roller not in contact with bronze-graphite sliding pads; • New assembly arrangement of the roller shaft for easy assembly and maintenance using Ringfeder locking elements;

15. Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas • ELEVATION BEARINGS AND ENCODER • PM#06 18-19 June 2006

16. Elevation bearing: Membrane interface modification for bearing housing extraction without box disassembly Seals modification Greasing system implementation Encoder assembly (on going) New pipes Layout in order to permit lubrication on the nipple in shadow of the tilt meter (ESO request)

18. Elevation bearing section

19. Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas • Quadripod Legs And Attachment • PM#04 17-18 May 2006

20. NEW APEX DESIGN:

21. NEW APEX DESIGN:

22. NEW APEX DESIGN AND NEW LEGS ATTACHMENT:

23. Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas • PLATFORMS DESIGN • PM#06- 18-19 July 2006

24. FEA model of the plafroms

25. First heigenfrequency 11.6 Hz • Static deformation

26. Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas • Metrology activity on site • PM#04 17-18 May 2006

27. THERMAL METROLOGY • General assumptions: • IN THE ACU AN OLD CONCEPT OF THERMAL METROLOGY WAS IMPLEMENTED: WITH THIS OLD CONCEPT THE POSITION OF THE SENSORS PUTTED IN THE BASE STRUCTURE WAS CONSIDERED IN A WRONG WAY • THE ACU SOFTWARE WAS CORRECTED AND UPDATED • THE CORRISPONDENCE BETWEEN THE PHYSICAL SENSORS AND THE ROWS OF THE MATRIX WAS WRONG: SOME SENSORS IN THE RIGHT ARM WAS READ BY ACU AS THEY WERE IN THE LEFT ARM • ALL THE SENSORS WERE CHECKED AND NOW THEY ARE READ BY ACU IN THEIR CORRECT POSITION • THE POINTING MODEL GIVE A POINTING ERROR GREATER THAN THE ERROR DUE TO THERMAL DISTORSION • Next Steps: • - New concept based on 78 thermal sensor (TBD) • Consolidated FEA model ready for optimization of position and numbers of thermal sensors • The system must be tested after the pointing model implementation in order to have evidence about the level of correction

28. WIND METROLOGY • General assumptions: • The new concept is based on two titlmeter mounted on the top arms • We are working with the Geomechanics in order to improve the dynamic behaviour of the titlmeters • We have to work in order to check only the error source that we need to correct: • Steady wind up to 6,5 m/sec • Fast motion mode TBD