LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 LBT672 ADAPTIVE SECONDARY UNITS Current status, acceptance test plan and specifications A. Riccardi, M.Xompero, D. Zanotti, L. Busoni INAF – Osservatorio Astrofisico di Arcetri D. Gallieni ADS International srl R. Biasi Microgate srl

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 MECHANICS WHERE WE ARE BACKPLATE COATING ISSUE PALNNED STEPS MECHANICS AT ELECTRONICS WHERE WE ARE OPEN ISSUES ELECTRONICS TESTING P45 TESTS FUNCTIONALITY AND OPTICAL TESTS REQUIREMENTS ELECTRO-MECHANICAL ACCEPTANCE ARCETRI TEST TOWER (ATT) FACILITY ADSEC OPTICAL LAYOUT AND ALIGNEMNT IN ATT OPTICAL ACCEPTANCE (SHELL FIGURE QUALITY, FLATTENING STABILITY) PRESENTATION OUTLINE

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 MECHANICS: WHERE WE ARE

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 MECHANICS: WHERE WE ARE

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 BACKPLATE COATING Silver layer by chemical coating  adhesion Gold layer by galvanic deposition  mechanical strength, age stability Galvanic bath problem  repeated two times Thermal stability problem on ring #7

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 MECHANICAL ALIGNMENT

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 INTEGRATION ROOM

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 NEXT STEPS BP finishing (ongoing, TBC by this week)

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 NEXT STEPS Dummy Shell installation test (by Nov.05) - pre-test next week w. G. Engineering Shell installation and dummy magnets gluing (by Dec.05) TS2 installation and magnets gluing (by Jan.06)

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 HAZARDS BP repair (local) Procedure assessment on BP(P1) - Dec.05  Jan.06 2w allocated in schedule after TS2 is removed Shells handling Procedure and tools assessment w. Guido B. on-site assistance […]

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 MECHANNICAL SHOP PROOF TEST 640a012, Is.A, days allocated before crating and shipping Unit#1 to Microgate HP#2 (1st ready) will be installed into the solar tower at this time Test with HP#2 (TBC) 3w DELAY on AIT management schedule (8 Sept. 2005)

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 ELECTRONICS: WHERE WE ARE

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 ELECTRONICS: WHERE WE ARE

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 NEW POWER BACKPLANE Complete testing and calibration at Microgate Verification on P45 (W47) Complete integration of other units (components in house !)

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 DISTRIBUTION BOARDS Distribution board type ‘A’ currently being integrated at Microgate After functional tests, repeat mechanical check at ADS Proceed with integration of other boards Mechanical matching tested on dummy boards at ADS

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 ELECTRONICS TEST & CALIBRATION Pre-screening (before integration w. mechanics). E.g. capsens board/actuator Full functional test and calibration Calibration data storage  System components can be replaced with no need to recalibrate the entire system Burn-in test: full power, high thermal load on single backplanes (half-crate). Moderate overload on fully integrated unit without thin shell

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 FUNCTIONAL TEST AT LOW TEMPERATURE Will be conducted on a cooled truck trailer, connected to a docking station (shipping company based at walking distance from Microgate – easy and safe transport of integrated unit) Temperature range: -20°C - +20°C Purpose: functional test (not performance). Includes verification of capacitive sensors calibration using ‘mechanical’ reference pad Verification with test thin shell mounted as an option

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 P45 NEXT STEPS Installation and verification of new power backplane Replace all boards and actuators with LBT672 spares (Capsens board V3.0, DSP board V3.2). Minimal differences w.r.t. currently installed electronics, but 1:1 test always useful! Tracing of P45 operation to verify system reliability New: system operation with two backplanes (2x BCU, real-time communication daisy chain, 2x reference signal generator) Repeat thermal stability tests on new electronics

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 Strong inconsistency between P45 and test-stand measurements. Test stand: ~10 ppm/°C – P45: up to 200 ppm/°C (???) To be understood! THERMAL STABILITY

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 ELECTRO MECHANICAL TESTS AT MICROGATE Elevation angles: 90°, 70°, 45°, 20° AO configuration ( ~ 70um gap) –Noise < 10nm rms –Modal settling time < 1.5ms (0.7 goal) –Tracking of turbulence (0.65asec seeing, 20m/s speed) < 50nm rms WF (goal 28nm) from capsens reading (diagnostic buffers) Chopping config ( ~ 100um gap) –±4asec (80um PtV) 5Hz 90% duty cycle (goal ±7asec, 140um PtV) –On-source tilt reproducibility 10mas rms (goal 3mas) Milestone: Adsec Unit Ready for Optical Tests

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 OPTICAL TESTS IN ARCETRI

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 REQUIREMENTS FOR STARTING OPTICAL TESTS Opto-mechanical accept. tests passed (Adsec ready for Optical test milestone) W acceptance test passed (W sensor ready for System Test milest) Stands and trolleys Hexapod accepted Hexapod TCS software working –Absolute and relative positioning –Rotation around a point Arcetri Test Tower facility working. 0.1°C stability= /10 focus error, per 15min (goal 1hour) Adsec procedure mounting on ATT tested w dummy Retro-reflecting optics and holder tested ( /10 PtV) Shell silver spraying successfully tested on dummy shells

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 ATT SCHEDULE

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 ARCETRI TEST TOWER FACILITY F2 F1 F/15.0 F/ mm mm 911mm Lab Winch

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 RETRO-REFLECTOR AND HOLDER 3cm 2cm Parabola+flat Only mirrors Telescope-like carbon fiber structure

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 Alignment procedure Interferom.: F/14 Mirror: F/15 1. Hex to move the spot on F1 2. Hex to move the spot on F2 keeping the spot on F1 3. Interf. Stage to set the focus 4. Hex+Interf. Stage to compensate spherical ab. Reference Optics mechanical pre-alignment: +/-3mm x-y (WFS +/-0.1 pix) +/-5mm z (WFS z + stage clearance) +/-2deg (F/1.1 instead of F/1.2) WFS BS

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 THERMAL FUNCTIONALITY TESTS In Arcetri Test Tower Temperature: 20°C, 10°C, 0°C, -5°C (goal -10°C) Pressure 700hPa (mountain pressure) Same electro-mechanical tests with same specifications We are considering the possibility to move this test in MG: no need of optical feedback Cooled container down to -20°C Conceptually part of electro-mechanical test But… extra cost (rent of container)

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 MIRROR FLATTENING Low order flattening using electrical signals (gap uniformity, refplate figure) Identification of capsens areas on interferometer frame (fiducials, min 6) Delta-commands = -WF/2 on capsens Iterate until no improvement or f>0.2N Local (given gap) calibration of capsens signals –3-5Hz sinusoidal Tip&tilt: 4D-interferometer (30fps) and capsens reading. FFT (demodulation) for calibration constants Iterate flattening after local calibration until no improvement or f>0.2

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 MIRROR FLATTENING SPECIFICATIONS T=ambient, ambient+10°C, ambient-10°C Flattening residual: – Min: < 65nm rms WF, peak force < 0.2N – Goal: < 30 nm rms WF, peak force < 0.07N Chopping flattening: –200nm rms (1/3 rms 0.2asec seeing,L0=20m) –100nm rms (Goal) Milestone: Flattened secondary, ready for AO test

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 FLATTENING UNKNOWNS Environmental disturbances (vibrations) Shape of shell after de-blocking Control effectiveness of chipped actuators (non-linearities)

LBT672 ADAPTIVE SECONDARYLBT AO Review Firenze - 10  11 November, 2005 THE END