1. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 1 Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas T2- Design Concept Phase Progress Meeting Nr. 4 - Venezia 17 & 18 May 2006

2. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 2 CDR Engineering and Design Activities: TaskActivityStatus Global FEM Model & Analysis Finite Element Analysis Wind Analysis Thermal Modeling & Analysis Stress Analysis & Fatigue Verification System Engineering Activities Engineering Calculation Activities Mass & Balance Budget Error Budget Lifetime, Reliability & Maintainability Analysis EMC Control Plan Spare Part List Metrology SystemDesign & Analysis Detail DesignSub-Systems Design ( Base Structure,…..)

3. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 3 Technical and Design Topics: Subreflector Mechanism: baseline Baseline requirement According to the Technical Specification, the baseline is an ACU controlled mechanism able to traslate and position the subreflector in 3 degrees of freedom Baseline solutions Three axes mechanism: 3 DoF: X, Y and Z as per requirements Specification displacements provided by three independent sets of linear guides + linear actuator compliant with mechanical interface and envelope requirements compliant with all other requirements Hexapod System: 6 DoF: in excess of requirements specification movements provided by six independent sets of fixed rotatory actuator + links compliant with mechanical interface and envelope requirements compliant (in excess of) with all other requirements

4. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 4 Technical and Design Topics: PerformanceSpecifications3AXHEX Range X axis± 5 mm ± 7 mm Range Y axis± 5 mm ± 7 mm Range Z axis± 10 mm ± 12 mm X, Y Minimum speed0.5 mm/sec Z Minimum speed2 mm/sec X, Y differential accuracy (steps 20 μm)10 μm Z differential accuracy (steps 20 μm)5 μm Position Repeatability Z± 5 μm Position Repeatability for cycles up to ± 1.5 mm± 20 μm Axial stiffness6 N/μm Bending stifness2.4 Nm/arcsec Minimum Central ApertureØ 360 mm Outer DiameterØ 640 mm Maximum Height355 mm Payload Mass140 kg Weight< 50 kg Operating Conditions-20°C + 20°C (40°C) Survival Conditions-30°C + 40°C Lifetime30 years

5. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 5 Technical and Design Topics: Three axes mechanism (1of 2) - SOL.A

6. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 6 Technical and Design Topics: Three axes mechanism (2 of 2) - SOL.A

7. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 7 Technical and Design Topics: Hexapod System - SOL.B

8. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 8 Technical and Design Topics: Hexapod System (1 of 2)- SOL.C

9. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 9 Technical and Design Topics: Hexapod System (2 of 2)- SOL.C

10. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 10 ESO Change Requests Status: ANTD-3300000-0-001-CRE “ Access to tilt degrees of freedom of the Subreflector” PerformanceSpecificationsCREImpacts Range X axis± 5 mm ± 16 mm Actuators range (insteade of 12) yes Range Y axis± 5 mm Range Z axis± 10 mm X, Y Minimum speed0.5 mm/sec Z Minimum speed2 mm/sec X, Y differential accuracy (steps 20 μm)10 μmIncremental(?)yes Z differential accuracy (steps 20 μm)5 μmIncremental(?)yes Position Repeatability Z± 5 μmtbd Position Repeatability for cycles up to ± 1.5 mm± 20 μmtbd Axial stiffness6 N/μm Bending stifness2.4 Nm/arcsec Minimum Central ApertureØ 360 mmtbd Outer DiameterØ 640 mmtbd Maximum Height355 mmtbd Payload Mass140 kg Weight< 50 kgtbd Operating Conditions-20°C + 20°C (40°C) Survival Conditions-30°C + 40°C Lifetime30 yearsyes

11. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 11 ESO Change Requests Status: ANTD-3300000-0-001-CRE “ Access to tilt degrees of freedom of the Subreflector” Subreflector Mechanism: CRE Baseline requirement According to the Technical Specification, the baseline is an ACU controlled mechanism able to traslate and position the subreflector in 3 degrees of freedom CRE impacts Exclusive use of an hexapod system with two additional rotations, controlled by ACU Range of actuators Accuracy of 0.002 considered as “incremental accuracy” Duty cycle, without any specific requirement for these movements specification (for the purpose of heat dissipation calculation), we propose the following: - Off-Axis Focus adjustment mode: One movement of 1.5deg in 10s once a day (24hours) - Off-Axis Focus switching mode: Continous operation of 0.15deg motion, 10s delay, return to initial position (0.15deg motion) for a total cycle duration 22s Other impacts: - increase of verification campaign (all systems) - additional calibration system - ACU Sw implementation - - Apex structure (tbd)

12. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 12 VLA Site activities: Drive System Failures detected Azimuth Drive: PTC Elevation Drive: PTC (?), connector and electronic drive Actions for prototype Complete Inspections and Tests on: EL segment electronic drive …..by Specific Laboratory and by Phase Preparation of a technical report Reparation of the components Actions for production Total re-design of the Drive System (Phase System) Alternative proposal from other Suppliers

13. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 13 Procurement Status: ItemActivity required to the SupplierStatus Apex StructureManufacture item and toolsOn-going Interface CylinderManufacture itemNo start Subreflector MechanismManufacture item and pre-assembly on ApexOn-going ACU SystemSW development and/or Hw supplyOn-going Drives SystemManufacture item and toolsOn-going Brakes SystemManufacture itemOn-going Encoders SystemManufacture itemOn-going Metrology SystemSupply components Manufacture item and tools No start Smoke Detectors Syst.Supply componentsNo start HVAC SystemSupply components and/or sub-systemOn-going

14. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 14 Procurement Status: Procurement Plan: Apex Structure 345678910111212345678910 CDRPPDR Inform. Contact Rfp Bidding phase Nego phase aoc manufacture

15. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 15 Procurement Status: Procurement Plan: Interface cylinder 345678910111212345678910 CDRPPDR Inform. Contact Rfp Bidding phase Nego phase aoc manufacture

16. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 16 Procurement Status: Procurement Plan: Subreflector Mechanism 345678910111212345678910 CDRPPDR Inform. Contact Rfp Bidding phase NP aoc Qualification program Manufacture

17. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 17 Procurement Status: V Procurement Plan: ACU System 345678910111212345678910 CDRPPDR Inform.Contact Rfp Bidding phase Nego phase aoc manufacture

18. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 18 Procurement Status: aoc Procurement Plan: Drives System 345678910111212345678910 CDRPPDR Inform. Contact Rfp Bidding phase NP aoc Qualification program Manufacture

19. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 19 Procurement Status: Procurement Plan: Brakes System 345678910111212345678910 CDRPPDR Inform. Contact Rfp Bidding phase Nego phase aoc manufacture

20. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 20 Procurement Status: Procurement Plan: Encoders System 345678910111212345678910 CDRPPDR Inform.Contact Rfp Bidding phase TBD TBD TBD TBD

21. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 21 Procurement Status: Procurement Plan: Metrology System 345678910111212345678910 CDRPPDR Inform.Contact Rfp Bidding phase TBD TBD TBD TBD

22. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 22 Procurement Status: Procurement Plan: Smoke Detectors Syst. 345678910111212345678910 CDRPPDR Inform. Contact Rfp Bidding phase NP aoc Manufacture

23. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 23 Procurement Status: Procurement Plan: HVAC System 345678910111212345678910 CDRPPDR Inform. Contact Rfp Bidding phase NP aoc Qualification program Manufacture v

24. Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 24 ItemQualification ActivityProcedure Apex Structure--------------- Interface Cylinder--------------- Subreflector MechanismComplete System: Full test (interfaces, functionality, cicles) on test bench 27.06.06 ACU System--------------- Drives SystemPrototype (0ne segment, tbd magnet, electronic components): Full test (interfaces, functionality, cicles) on test bench 12.07.06 Brakes System------------- Encoders SystemComponentsmiddle of July Metrology SystemComponentsmiddle of July Smoke Detectors Syst. HVAC SystemComponents18.06.06 Qualification Program: