OWL Copenhagen, July 2004 A 100-m class optical & near-infrared telescope for the next decade.
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OWL Copenhagen, July 2004 A 100-m class optical & near-infr telescope for the next de
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Transcript of OWL Copenhagen, July 2004 A 100-m class optical & near-infrared telescope for the next decade.
OWLCopenhagen, July 2004
A 100-m class optical & near-infraredtelescope for the next decade
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Corning, N.Y., 1936Corning, N.Y., 1936
Schott, Mainz, 1992Schott, Mainz, 1992
Feasibility – progress of technology
Glass-making Slowly evolving technology Extrapolation from 5-m
required active optics ! Not easily scalable
Glass-making Slowly evolving technology Extrapolation from 5-m
required active optics ! Not easily scalable
Reosc, St Pierre du Perray, 1999Reosc, St Pierre du Perray, 1999
Wavefront control In-situ control of performance Dealing with inevitable error sources Tolerances relaxation Scalable
Wavefront control In-situ control of performance Dealing with inevitable error sources Tolerances relaxation Scalable
Optical figuring Metrology-dependent Rapid evolution Scalable (somewhat)
Optical figuring Metrology-dependent Rapid evolution Scalable (somewhat)
8-m dia., 8.5 nm RMS8-m dia., 8.5 nm RMS
VLT (Subaru, Gemini)Active optics
Hobby-EberlyLow-cost structures / optics
Adaptiveoptics
KeckOptical segmentation
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Optical design
Adaptive, conjugated to pupil;First generation
Adaptive, conjugated to pupil;First generation
Adaptive, conjugated to 8km;Second generation
Adaptive, conjugated to 8km;Second generation
M1 Covers
M2 Handling tool
Sliding enclosure
Maintenance facility
Azimuth tracks
Altitude bearing
Azimuth structure & bogies
Altitude tracks
Altitude cradles& bogies
Structure ribs (6-fold symmetry)
Corrector & instrumentation
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Self-similar fractal mechanical design(with all dimensions as multiple of segment size)
Low production, transport, integration & maintenance cost Optimal loads transfer to foundations Low thermal inertia Low mass (14,800 tons …) High stiffness (2.6 Hz)
Self-similar fractal mechanical design(with all dimensions as multiple of segment size)
Low production, transport, integration & maintenance cost Optimal loads transfer to foundations Low thermal inertia Low mass (14,800 tons …) High stiffness (2.6 Hz)
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Controlled opto-mechanical system
Pre-setting bring optical system into linear regimeMetrology: internal, tolerances ~ 1-2 mm, ~5 arc secsCorrection: re-position Corrector, M3 / M4 / M5
Segments phasing keep M1 and M2 phased within tolerancesMetrology: Edge sensors, Phasing WFSCorrection: Segments actuators
Field Stabilization cancel “fast” image motionMetrology: Guide probe Correction: M6 tip-tilt (flat, exit pupil, 2.35-m)
Active optics finish off alignment / collimation relax tolerances, control performance & prescription
Metrology: Wavefront sensor(s)Correction: Rotation & piston M5; M3 & M4 active deformations
Adaptive optics atmospheric turbulence, residualsMetrology: Wavefront sensor(s)Correction: M5, M6, …
Pre-setting bring optical system into linear regimeMetrology: internal, tolerances ~ 1-2 mm, ~5 arc secsCorrection: re-position Corrector, M3 / M4 / M5
Segments phasing keep M1 and M2 phased within tolerancesMetrology: Edge sensors, Phasing WFSCorrection: Segments actuators
Field Stabilization cancel “fast” image motionMetrology: Guide probe Correction: M6 tip-tilt (flat, exit pupil, 2.35-m)
Active optics finish off alignment / collimation relax tolerances, control performance & prescription
Metrology: Wavefront sensor(s)Correction: Rotation & piston M5; M3 & M4 active deformations
Adaptive optics atmospheric turbulence, residualsMetrology: Wavefront sensor(s)Correction: M5, M6, …
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From concept to sky testing: APE
Active Phasing Experiment
Segmenting the VLT
Laboratory & on-sky evaluation of up to 3 phasing techniques
Integration of phasing into global wavefront control
On-sky by 2007
Active Phasing Experiment
Segmenting the VLT
Laboratory & on-sky evaluation of up to 3 phasing techniques
Integration of phasing into global wavefront control
On-sky by 2007
MCAO simulationAdaptive opticsCompensation of atmospheric turbulence
2 arc minutes field, =2.5 m2 adaptive mirrors, 8000 actuators each
3 guide stars
Sqrt stretch
Not only simultations: Multi-conjugate Adaptive
optics Demonstrator (MAD) on-sky by 2005
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Cost estimate (capital investment, 2002 M€)
Diffraction-limited instrumentation (acceptable étendue !)Assumes “friendly site” Average seismicity (0.2g) Moderate altitude Average wind speed Moderate investment in infrastructures
SUMMARY MEuros
OPTICS 406
Primary & secondary mirror units 355.2
M3 unit 14.4
M4 unit 21.4
M5 temporary unit 5.3M6 temporary unit 10.1
ADAPTIVE OPTICS 110
M5/M6 design & prototypes 10
M6 AO unit 25
M5 AO unit 35XAO units 20LGS 20
MECHANICS 185
Azimuth 53.8
Elevation 34.9
Cable wraps 5.0
Azimuth bogies (incl. motors) 14.7Altitude Bogies & bearings 5.7Mirror shields 15.0Adapters 6.0Erection 50.0
CONTROL SYSTEMS (*) 17Telescope Control System 5.0M1 Control System 8.0M2 Control System 2.0Active optics Control System 2.0
CIVIL WORKS 170
Enclosure 40.4
Technical facilities 35.0
Site infrastructure 25.0
Concrete 70.0
INSTRUMENTATION 50
INSTRUMENTATION 50
Total without contingency 939 938.9
(*) High level cs only; local cs included in subsystems
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Cost estimates (industrial studies)
SiC A + Overcoating1
SiC B + Overcoating2
SiC B + Overcoating3
Glass-ceramics C Glass-ceramics D
Substrate & polishable overcoating
To
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Polishing
Overcoating
Blanks
2002 ESO ESTIMATE
Primary & secondary mirror segments; 1.8-m; polished, prices ex works.
Blanks: SiC (2 suppliers A and B) with overocatings (3 suppliers 1, 2, 3)
Glass-Ceramics (2 suppliers C and D)
Polishing: 2 suppliers, only one shown (both agree within 10%)
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Maximum reliance on proven solutions, from supply to operationsOptimized geometry (interface optics-mechanics)All parts fitting in 40-ft containers1.6-m all-identical segments (~3000 units),single optical reference for polishing12.8-m standard structural modules (integer multiple of segment size)Friction drive (bogies), hydraulic connection
Maximum reliance on proven solutions, from supply to operationsOptimized geometry (interface optics-mechanics)All parts fitting in 40-ft containers1.6-m all-identical segments (~3000 units),single optical reference for polishing12.8-m standard structural modules (integer multiple of segment size)Friction drive (bogies), hydraulic connection
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ECMBOOSTEC
Meanwhile …
Extremely Large Telescope Design Study
Extremely Large Telescope Design Study
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ELT Design StudyELT Design Study
The R&D part of a phase BThe R&D part of a phase B
ObjectivesObjectives
– Technology development towards a European ELTTechnology development towards a European ELT– Preparatory work for observatory designPreparatory work for observatory design– Top level requirementsTop level requirements– Academic & industrial synergy Academic & industrial synergy
Design-independentDesign-independent
Proposal to EC within FP6 - ApprovedProposal to EC within FP6 - Approved
– 39 partners, 47 WPs / Tasks39 partners, 47 WPs / Tasks– 42 M42 M€ total, 22 M€ requested€ total, 22 M€ requested– Timescale 2005-2008 Timescale 2005-2008
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ELT Design - OutlineELT Design - Outline
Wavefront control technologiesWavefront control technologies– Low-cost, high accuracy actuators (up to 10,000 needed)Low-cost, high accuracy actuators (up to 10,000 needed)– Low-cost, high accuracy metrology systems (up to 20,000)Low-cost, high accuracy metrology systems (up to 20,000)– Integrated control systems, APEIntegrated control systems, APE– 7-segments breadboard, exposed to natural wind7-segments breadboard, exposed to natural wind
Adaptive optics Adaptive optics – Development of ultra-thin adaptive mirrorsDevelopment of ultra-thin adaptive mirrors– Control strategiesControl strategies– Subsystems conceptual designSubsystems conceptual design
Materials & processes (e.g. SiC for segments)Materials & processes (e.g. SiC for segments)Composite materials for specific structural elementsComposite materials for specific structural elementsMagnetic levitation (telescope kinematics)Magnetic levitation (telescope kinematics)Site searchSite searchScience instruments designsScience instruments designs
Wavefront control technologiesWavefront control technologies– Low-cost, high accuracy actuators (up to 10,000 needed)Low-cost, high accuracy actuators (up to 10,000 needed)– Low-cost, high accuracy metrology systems (up to 20,000)Low-cost, high accuracy metrology systems (up to 20,000)– Integrated control systems, APEIntegrated control systems, APE– 7-segments breadboard, exposed to natural wind7-segments breadboard, exposed to natural wind
Adaptive optics Adaptive optics – Development of ultra-thin adaptive mirrorsDevelopment of ultra-thin adaptive mirrors– Control strategiesControl strategies– Subsystems conceptual designSubsystems conceptual design
Materials & processes (e.g. SiC for segments)Materials & processes (e.g. SiC for segments)Composite materials for specific structural elementsComposite materials for specific structural elementsMagnetic levitation (telescope kinematics)Magnetic levitation (telescope kinematics)Site searchSite searchScience instruments designsScience instruments designs
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WEBWEBWEBWEB
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Silicon Carbide prototypesSilicon Carbide prototypes
1-m class, 8 pcs., different overcoatings1-m class, 8 pcs., different overcoatings 4 blanks already at ESO4 blanks already at ESO Explore overcoating & figuring processes,Explore overcoating & figuring processes,
check for bimetallic effectscheck for bimetallic effects AdvantagesAdvantages
– Stiffer, lighter, better thermo-mechanicalStiffer, lighter, better thermo-mechanicalproperties (than glass)properties (than glass)
– Higher control bandwidth (position)Higher control bandwidth (position)
– HardnessHardness
– Lighter, stiffer telescope structureLighter, stiffer telescope structure
– ~20 years of development, space-qualified~20 years of development, space-qualified
– Potentially cost-effective if appropriate designPotentially cost-effective if appropriate design
BUTBUT– Needs qualification for segmented aperturesNeeds qualification for segmented apertures
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Friction drive breadboardFriction drive breadboard
Mandatory – Hydraulic pads / tracks not an option !
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Timeframe
2000
2005
2010
2015
2020
Phase A review
Phase A
APE on sky
ELT Design Study
Phase B
Site selection
Phase C/D
Groundbreaking
First light (50-m)
Start of science (60-m)
Completion
Driven by funding, not by technology
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OWL in brief
A concept already at an advanced stage of design Design supported by analysis & competitive industrial studies Cost estimate > 50% completed, supported by competitive studies Cost-effective design principles & solutions allow major jump in capability
Substantial science at an early stage
European-wide technology & concepts development Industrial & academic synergy ELTs “building blocks”, design-independent
Prominent role of industry from earliest phase of design Design minimizes industrial risks Industrial solutions to design / fabrication / integration / maintenance R&D focused on critical areas Ample business opportunities – in R&D and serial production
A concept already at an advanced stage of design Design supported by analysis & competitive industrial studies Cost estimate > 50% completed, supported by competitive studies Cost-effective design principles & solutions allow major jump in capability
Substantial science at an early stage
European-wide technology & concepts development Industrial & academic synergy ELTs “building blocks”, design-independent
Prominent role of industry from earliest phase of design Design minimizes industrial risks Industrial solutions to design / fabrication / integration / maintenance R&D focused on critical areas Ample business opportunities – in R&D and serial production
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