MCAO
MCAO for Gemini South
Preliminary Design Review
May 24-25
Hilo, Hawaii
MCAO
MCAO Project Overview
Brent Ellerbroek
Presentation Outline
MCAO
• Gemini AO program overview
• MCAO context
–
–
–
–
Concept and benefits
Other MCAO projects
MCAO and Conventional LGS AO for Gemini-South
MCAO and Altair
• Project schedule, organization, and partners
• Progress during the Preliminary Design phase
• PDR groundrules, logistics, and schedule
May 24-25, 2001
MCAO Preliminary Design Review
3
MCAO
Gemini AO Requirements and MCAO
• Science Requirements Document, 1992:
– Tip/tilt correction: Image quality in K band better than 0.1
arc sec over a 1 arc min field.
– Higher-order correction: Delivered on-axis H band Strehl
of 50% under median seeing conditions
• Altair Science Requirements, 1995:
– LGS AO: Objective is to increase sky coverage at above
performance levels
• MCAO on Gemini South can provide
– Mean H band Strehl of 40% over square 1 arc minute field
– Sky coverage equal or superior to conventional LGS AO
• 18% sky coverage at galactic pole, 77% at 30 degree
latitude
May 24-25, 2001
MCAO Preliminary Design Review
4
MCAO
Gemini AO System Summary
System
Telescope
Order/Type
Hokupa’a
North
36/NGS Curvature Now
Hokupa’a-85
North
85/NGS Curvature ?
Altair
North
12 by 12/NGS
Shack Hartmann
2nd Sem
2002
Altair LGS upgrade
North
12 by 12/LGS
Shack Hartmann
1st Sem.
2004
GSAO—Conventional
LGS AO Mode
South
16 by 16/LGS
Shack Hartmann
1st Sem.
2005
GSAO—MCAO Mode
South
16 by 16/LGS
Shack Hartmann
1st Sem.
2006 (TBR)
May 24-25, 2001
MCAO Preliminary Design Review
Availability
5
MCAO
MCAO Concept, Benefits, Requirements
• Wide field-of-view turbulence compensation
– Multiple deformable mirrors conjugate to distinct ranges
– Multiple wave front sensing guidestars and tomography
• Highly uniform point spread functions
– Improved observing efficiency, simplified data reduction
• Satisfactory sky coverage using laser guide stars
– 3 tip/tilt natural guide stars correct tilt and tilt anisoplanatism
• Feasible AO component requirements
– Orders of individual mirrors and sensors equivalent to
conventional AO systems
– Processing requirements now straightforward
– Laser requirements equivalent to conventional LGS AO on a perbeacon basis
May 24-25, 2001
MCAO Preliminary Design Review
6
MCAO Demonstration Programs
•
•
•
•
MCAO
Three programs announced since Gemini MCAO CoDR
Demonstrators, not facility instruments
All expect first results within 2-3 years
ESO
– Multiple NGS WFS and two low-order bimorph DM’s
– “Conventional” and/or “layer-oriented” MCAO
• University of Arizona
– 5 Rayleigh guide stars, two deformable mirrors
• Palomar/CfAO
– Tomographic NGS wave front sensing with multiple ShackHartmann WFS
– Potential future upgrades to multiple DM’s and laser beacons
May 24-25, 2001
MCAO Preliminary Design Review
7
MCAO and Conventional LGS
AO for Gemini-South
MCAO
• Gemini Board has approved LGS AO for Gemini-South
• MCAO is our long-term goal
• Conventional LGS AO is the first step
– Subset of MCAO system with a single DM, WFS, LGS
– Designs fully compatible
• No penalty (beyond two reflections) for including MCAO
upgrade path in LGS AO design
• MCAO depends on several milestones
– Board-mandated technical peer review (this PDR)
– Review of science case and costs (CDR—late 2002)
– Successful laser development process (2002/03)
May 24-25, 2001
MCAO Preliminary Design Review
8
MCAO and Altair
MCAO
• Conjugation to altitude unsuitable for Cerro Pachon
– ~60% of turbulence power near the ground
• Systems will employ common LGS infrastructure
–
–
–
–
Safety systems
Beam transfer optics
Laser launch telescope
Control systems
• Laser systems will be specified/procured separately
– Single or multiple lasers for MCAO
– Pulsed vs. CW issues for MCAO
– Need to procure Altair laser system now
May 24-25, 2001
MCAO Preliminary Design Review
9
MCAO Project Milestones
•
•
•
•
•
•
•
•
•
•
•
•
MCAO
Feasibility Study Report: November 1999
Conceptual Design Review: May 2000
Preliminary Design Review: May 2001
Subsystem RFPs (excepting lasers): July-August 2001
Laser System RFP: Mid-2002
Subsystem Critical Design Reviews: July-August 2002
System CDR: September 2002
Laser System CDR: Mid-2003
AO Module lab integration: 11/03-6/04
LGS subsystems integration (initial laser): 2/04-9/04
System integration and test (initial laser): 07/04-12/04
Follow-on laser integration and test: 2005
May 24-25, 2001
MCAO Preliminary Design Review
10
MCAO
Preliminary
Design Project
Team
MCAO
Associate Director
For Engineering
Jim Oschmann
Project Manager
Brent Ellerbroek
Project Scientist
Francois Rigaut
Chip Kobulnicki (U. Wisconsin)
Ivan Baldry (AAO)
Eric Steinbring (UCSC)
Workshop leaders and chairs
Contracts
Andy Flach
System Engineering
/Modeling
Brent Ellerbroek
Glen Herriot (HIA)
Jean-Pierre Veran (HIA)
Software/Controls
Corinne Boyer
Les Saddlemyer (HIA)
the Optical Sciences Company
SHAKTIWARE
AO Module
Eric James
Mechanics
Andre Anthony (HIA)
Joeleff Fitsimmons (HIA)
Kei Szeto (HIA)
May 24-25, 2001
Coherent Technologies
U Chicago/LiteCycles
Starfire Optical Range
Beam Transfer Optics
/Launch Telescope
Celine d’Orgeville
Optics
Richard Buchroeder (ODS)
Jim Stillburn (HIA)
Laser System
Celine d’Orgeville
Electronics
Mark Hunten
Paul Clark (Durham)
Tim Hardy (HIA)
Safety System
Jacques Sebag
Jim Catone
Brian Baumann (LLNL)
Don Gavel (LLNL)
MCAO Preliminary Design Review
11
MCAO
MCAO Project Partners
• Preliminary design support
– HIA (RTC electronics/algorithms, reliability analysis, WFS CCD
electronics, NGS T/T WFS design, mechanical design)
– LLNL (BTO/LLT design/modeling)
– U Durham (DM electronics)
• Laser risk reduction projects
– AFRL, CTI, U Chicago/LiteCycles (CfAO support)
• Real-time control benchmarking/architecture
– HIA, SHAKTIWARE (ESO support), tOSC
• CTIO sodium layer measurements
– Imperial College (ESO and NOAO support)
• Laser safety and traffic control
– Keck Observatory
• Algorithm and modeling collaborations
– AFRL, CELT, CfAO, ESO, HIA
May 24-25, 2001
MCAO Preliminary Design Review
12
MCAO
Preliminary Design Phase Highlights
• Subsystem design
–
–
–
–
AO Module opto-mechanical design
BTO/LLT layout, budgets, mechanical design
RTC benchmarking, architecture studies and algorithms
Control system software specifications
• Laser risk reduction
– 10 W, 1.319 mm, mode-locked CW, Nd:YAG laser demo
• Science case
– Santa Cruz MCAO science workshop
• Management and system engineering
– Management and integration/test plans
• Modeling and analysis
– Wave optics propagation simulation
May 24-25, 2001
MCAO Preliminary Design Review
13
Technical Risks—CoDR and Now
Subsystem/Component
Issue(s)
Progress
Laser
Performance,
reliability
Risk reduction
demonstrations
AOM optical design
Packaging,performance Improved design
MCAO
1 vs, 5 LGS WFS Cameras Packaging
Feasible layout defined
LGS/NGS Beamsplitter
Feasibility
ROM quote
RTC
Computational load
Algorithm specifics
Benchmarks
Algorithm specified
LLT/BTO optical design
Incomplete concept
Deployable LLT
Approach revised
Error budgets defined
Fixed LLT + periscope
AOM HVA electronics
Packaging
Heat dissipation
Space available
Heat load acceptable
Reliability/availability
Not evaluated
Evaluated
May 24-25, 2001
MCAO Preliminary Design Review
14
PDR Objectives
MCAO
• Present results of the Preliminary Design effort
–
–
–
–
–
Science case
System performance estimates
System and subsystem design
Laser requirements and options
Program cost and schedule estimates
• Committee peer review of technical approach
– Approval necessary for pursuit of MCAO
• Obtain more general feedback from the Committee
– Design suggestions
– Integration and test plan
– Cost estimates, management plan, science case
May 24-25, 2001
MCAO Preliminary Design Review
15
Logistics/Procedures
MCAO
• Lunch here (both days)
• Please sign attendance sheet
• Design report available electronically
– Viewgraphs and selected appendices available upon request
• Please document comments for the committee
and/or Gemini on the forms provided
• Friday PM session restricted to the committee,
vendors, and Gemini management chain
• We will keep to schedule
– Hold all but most essential questions to end of presentation
– Committee questions first, audience questions as time
allows (and during breaks)
May 24-25, 2001
MCAO Preliminary Design Review
16
MCAO
PDR Agenda
Thursday, 5/24
0800 Welcome
0805 Project overview
0830 Science case
0930 Break
0945 System overview
1015 System modeling
1100 AO Module optics
1145 Lunch
May 24-25, 2001
1245 AO Module mechanics
1340 AO Module electronics
1400 Break
1415 Beam Transfer Optics
1510 Laser Launch Telescope
1545 Closed committee session
1800 Adjourn
MCAO Preliminary Design Review
17
MCAO
PDR Agenda
Friday, 5/25
0800 Laser System
0900 CTIO Sodium Studies
0915 Control System
0945 Break
1000 RTC Electronics
1045 Safety System
1100 Availability analysis
1130 Closed vendor Sessions
1200 Lunch
May 24-25, 2001
1300
1400
1700
1800
Cost and schedule
Committee session
Committee report
Adjourn
MCAO Preliminary Design Review
18
MCAO
PDR Agenda
Thursday, 5/24
0800 Welcome
0805 Project overview
0830 Science case
0930 Break
0945 System overview
1015 System modeling
1100 AO Module optics
1145 Lunch
May 24-25, 2001
1245 AO Module mechanics
1340 AO Module electronics
1400 Break
1415 Beam Transfer Optics
1510 Laser Launch Telescope
1545 Closed committee session
1800 Adjourn
MCAO Preliminary Design Review
19