the on-sky ngs/lgs moao demonstrator for eagle tim morris durham university
TRANSCRIPT
The on-sky NGS/LGS MOAO The on-sky NGS/LGS MOAO demonstrator for EAGLEdemonstrator for EAGLE
Tim MorrisTim MorrisDurham UniversityDurham University
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Talk overviewTalk overview
MOAO with EAGLEMOAO with EAGLE CANARY conceptCANARY concept Optomechanical designOptomechanical design Subsystem performanceSubsystem performance System performanceSystem performance System calibration tasksSystem calibration tasks
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
MOAO with EAGLEMOAO with EAGLE
With the current baseline design, EAGLE will:With the current baseline design, EAGLE will: use 6 LGS and up to 5 NGS to map the turbulence above the E-use 6 LGS and up to 5 NGS to map the turbulence above the E-
ELTELT correct up to 20 x ~2” diameter science fields anywhere within correct up to 20 x ~2” diameter science fields anywhere within
the central 5’ diameter field using open-loop AOthe central 5’ diameter field using open-loop AO 250Hz frame rate250Hz frame rate
E-ELT has a deformable ‘secondary’ that will be used as E-ELT has a deformable ‘secondary’ that will be used as a closed-loop woofer (GLAO-like DM)a closed-loop woofer (GLAO-like DM)
EAGLE is both a closed and open-loop systemEAGLE is both a closed and open-loop system
30% ensquared energy with 75mas (H-band) required 30% ensquared energy with 75mas (H-band) required performanceperformance
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
MOAO with EAGLE: big questionsMOAO with EAGLE: big questions
Can we achieve tomographic reconstruction to the required Can we achieve tomographic reconstruction to the required accuracy over such wide fields? accuracy over such wide fields?
Can we reliably control a DM in open-loop?Can we reliably control a DM in open-loop? How do we calibrate the system?How do we calibrate the system? How accurately do we need to measure the Cn2 profile to optimise performance? How accurately do we need to measure the Cn2 profile to optimise performance? What is the impact of running the system with both open and closed loop DMs?What is the impact of running the system with both open and closed loop DMs? How do we compensate for LGS specific effects that can impact MOAO How do we compensate for LGS specific effects that can impact MOAO
performance?performance? What are the principle performance drivers required when designing an MOAO What are the principle performance drivers required when designing an MOAO
system?system? What is the best way to combine both NGS and LGS WFS signals to measure What is the best way to combine both NGS and LGS WFS signals to measure
tomography?tomography? Answer as many of these questions as possible as soon as possible Answer as many of these questions as possible as soon as possible
to feed into the EAGLE designto feed into the EAGLE design Some can be (and have been) answered in simulation or using a lab Some can be (and have been) answered in simulation or using a lab
system such as SESAMEsystem such as SESAME
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
CANARY conceptCANARY concept
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
CANARY AimsCANARY Aims
Perform NGS then LGS based tomographic WFSingPerform NGS then LGS based tomographic WFSing Perform open-loop AO correction on-skyPerform open-loop AO correction on-sky Develop calibration and alignment techniquesDevelop calibration and alignment techniques Fully characterise system and subsystem performanceFully characterise system and subsystem performance
Create a single MOAO channel EAGLE as closely as Create a single MOAO channel EAGLE as closely as possibly using the 4.2m William Herschel Telescopepossibly using the 4.2m William Herschel Telescope
Effectively a 1/10Effectively a 1/10thth scale model of E-ELT using a 10km Rayleigh scale model of E-ELT using a 10km Rayleigh LGSLGS
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
CANARY phased developmentCANARY phased development
Based around a set of reconfigurable optical Based around a set of reconfigurable optical modules to allow ‘easy’ changes between three modules to allow ‘easy’ changes between three CANARY phasesCANARY phases Phase A: Low-order NGS-only MOAO (2010)Phase A: Low-order NGS-only MOAO (2010) Phase B: Low-order LGS MOAO (2011)Phase B: Low-order LGS MOAO (2011) Phase C: High-order LGS + NGS MOAO (2012)Phase C: High-order LGS + NGS MOAO (2012)
All phases will include an extensive calibration All phases will include an extensive calibration and diagnostics packageand diagnostics package
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Diagnostics and Performance monitoringDiagnostics and Performance monitoring On-axis NGS WFS behind AO corrected focal plane On-axis NGS WFS behind AO corrected focal plane
(Truth Sensor)(Truth Sensor) On-axis NIR imaging camera (Science Verification On-axis NIR imaging camera (Science Verification
Camera)Camera) High-order high-bandwidth DM figure sensorHigh-order high-bandwidth DM figure sensor SLODAR analysis performed using open-loop WFSsSLODAR analysis performed using open-loop WFSs External turbulence profilersExternal turbulence profilers
SLODARSLODAR MASS-DIMMMASS-DIMM
Telescope simulatorTelescope simulator Turbulent phase screensTurbulent phase screens NGS and LGS alignment and calibration sourcesNGS and LGS alignment and calibration sources
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Phase A : NGS MOAOPhase A : NGS MOAO
Components:Components: Low-order 8x8 DMLow-order 8x8 DM 3 x L3CCD open-loop NGS WFSs3 x L3CCD open-loop NGS WFSs Open-loop optimised Fast Steering Open-loop optimised Fast Steering
MirrorMirror Hardware accelerated Real Time Hardware accelerated Real Time
control systemcontrol system NGS MOAO Calibration UnitNGS MOAO Calibration Unit
WHTNasmyth
Calibration Unit
NGS Pickoffs
3 x NGS WFS
NGS FSM
Low-order DM
Science Verification
Truth Sensor
Figure Sensor
GHRIL Derotator
Phase A: NGS MOAO
NGS WFS
NGS WFS
NGS WFS
10" Truth sensor& IR camera FOV
2.5’ Derotated WHT field
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Phase B: Low-order LGS MOAOPhase B: Low-order LGS MOAO
New modules include:New modules include: Electronically shuttered LGS WFS CCDElectronically shuttered LGS WFS CCD Modified GLAS launch systemModified GLAS launch system LGS dichroic and relay systemLGS dichroic and relay system LGS MOAO Calibration UnitLGS MOAO Calibration Unit
WHTNasmyth
Calibration Unit
NGS Pickoffs
3 x NGS WFS
NGS FSM
Low-order DM
Science Verification
Truth Sensor
LGS Pickoffs
4 x LGS WFS
GHRIL Derotator
Figure Sensor
GLAS Laser
LGS Rotator
GLAS BLT
Diffractive Optic
LGSFSM
LGS Dichroic
Phase B: Low-order LGS MOAO
LGS WFS
1.5’ Diameter LGS asterism
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Phase C: High-order LGS MOAOPhase C: High-order LGS MOAO
Closest resemblance to proposed EAGLE MOAO implementationClosest resemblance to proposed EAGLE MOAO implementation Largest upgrade here is to the RTCS. From Phase B we have:Largest upgrade here is to the RTCS. From Phase B we have:
~ 2 times increase in pixel bandwidth~ 2 times increase in pixel bandwidth ~ 5 times increase in slope bandwidth~ 5 times increase in slope bandwidth ~ 17 times increase in actuator bandwidth~ 17 times increase in actuator bandwidth
WHTNasmyth
Calibration Unit
NGS Pickoffs
3 x NGS WFS
NGS FSM
Low-order DM
Science Verification
Truth Sensor
Figure Sensor
LGS Pickoffs
4 x LGS WFS
GHRIL Derotator
MEMS DM
GLAS Laser
LGS Rotator
GLAS BLT
Diffractive Optic
LGSFSM
LGS Dichroic
Phase C: High-order woofer-tweeter LGS MOAO (woofer closed loop)
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Optomechanical designOptomechanical design
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Phase A optical designPhase A optical design
Input Focal Plane
Output focal plane Truth Sensor focal plane
Science Verification Camera focal plane
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Phase B optical designPhase B optical designLGS TT mirror
NGS WFS placed at corrected focal plane
Acquisition camera moved to input focal plane
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Phase C optical design conceptPhase C optical design concept
Possible locations of MEMS MOAO DM
LGS WFS(s) moved behind closed-loop DM
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
NGS WFS AssemblyNGS WFS Assembly
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Telescope SimulatorTelescope Simulator
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Subsystem performanceSubsystem performance
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Open-loop DM ControlOpen-loop DM Control
4% open-loop error with hard PZT DM demonstrated in 4% open-loop error with hard PZT DM demonstrated in laboratory with SESAMElaboratory with SESAME
40nm RMS error if a 1000nm RMS DM surface is requested40nm RMS error if a 1000nm RMS DM surface is requested
Figure sensor could be used to control any long term Figure sensor could be used to control any long term drifts in DM surface shapedrifts in DM surface shape
Will introduce some additional latencyWill introduce some additional latency Has been used with a Xinetics DM and produces a similar Has been used with a Xinetics DM and produces a similar
surface error to the hard PZT DMsurface error to the hard PZT DM
Open loop control of a DM doesn’t seem to be a problem Open loop control of a DM doesn’t seem to be a problem for CANARY low-order DMfor CANARY low-order DM
High-order MEMS DM open-loop control has already been High-order MEMS DM open-loop control has already been demonstrateddemonstrated
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Subsystem performance: LGS LaunchSubsystem performance: LGS Launch Test system installed on WHT and tested in MayTest system installed on WHT and tested in May Uses DOE in GLAS launch system to create a 4 star asterism (MMT Uses DOE in GLAS launch system to create a 4 star asterism (MMT
approach)approach) Several possible asterisms available by changing DOESeveral possible asterisms available by changing DOE
10 to 90” diameter asterisms (takes about 15 minutes)10 to 90” diameter asterisms (takes about 15 minutes) 80% of light into 4 diffracted LGS beams but altitude is lowered c.f. GLAS80% of light into 4 diffracted LGS beams but altitude is lowered c.f. GLAS
Still want an upgraded laser to increase WFS SNRStill want an upgraded laser to increase WFS SNR Software problem with LGS detector meant range gated images couldn’t be Software problem with LGS detector meant range gated images couldn’t be
obtainedobtained
Non-gated image of ~40” LGS radius asterism at 6.7km
DOE mounted in rotation stage at GLAS BLT entrance
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
RTCSRTCS
Hybrid FPGA-CPU Realtime Control SystemHybrid FPGA-CPU Realtime Control System FPGA pixel processing developed for HOT and SPARTAFPGA pixel processing developed for HOT and SPARTA Reconstructor in CPUReconstructor in CPU DM control in CPUDM control in CPU
Currently runs at Phase A/B at 300-400Hz using a single Currently runs at Phase A/B at 300-400Hz using a single threaded reconstructor pipelinethreaded reconstructor pipeline
Latency and jitter to be measuredLatency and jitter to be measured
Upgrade required to cope with high-order LGS WFSs Upgrade required to cope with high-order LGS WFSs and DM in Phase Cand DM in Phase C
Parallelise reconstructorParallelise reconstructor GPU accelerationGPU acceleration
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
RTCS overviewRTCS overview
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
System performanceSystem performance
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Phase A PerformancePhase A Performance
Monte-Carlo simulations performed using independent codes in Durham Monte-Carlo simulations performed using independent codes in Durham and Paris and Paris
Single open-loop DMSingle open-loop DM 8x8 actuators 8x8 actuators DM (and science path) on-axisDM (and science path) on-axis
3 x NGS WFSs3 x NGS WFSs Off-axis (30” to 90”)Off-axis (30” to 90”) 7 x 7 subapertures7 x 7 subapertures 0.1e- read noise0.1e- read noise Mv = 8 to 14Mv = 8 to 14 250Hz frame rate250Hz frame rate
Representative summer La Palma turbulence profile usedRepresentative summer La Palma turbulence profile used1
rr00 = 12cm = 12cm 45% @ 0km45% @ 0km 15% @ 2.5km15% @ 2.5km 30% @ 4km30% @ 4km 10% @ 13.5km10% @ 13.5km
1 Fuensalida et al, RevMexAA, 31, 84-90 (2007)
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Simulated PerformanceSimulated PerformanceSource of errorSource of error WFE (nm rms)WFE (nm rms)
WFS open-loop estimationWFS open-loop estimation 63 (from YAO)63 (from YAO)
WFS noise (quantum + readout)WFS noise (quantum + readout) 40 at m40 at mRR=10=10
80 at m80 at mRR=12=12
190 at m190 at mRR=14=14
Tomographic reconstruction (30’’ radius)Tomographic reconstruction (30’’ radius) 260 (GLAO least-square)260 (GLAO least-square)220 (tomographic least square)220 (tomographic least square)170 (L&A MMSE) (Vidal et al)170 (L&A MMSE) (Vidal et al)
DM fittingDM fitting 140140
DM open-loop errorDM open-loop error 4848
Tip-tilt open-loop errorTip-tilt open-loop error 2626
Temporal and aliasingTemporal and aliasing 113113
Residual high-orders from opticsResidual high-orders from optics 5050
TOTALTOTAL mmRR=12 : 285 to 340=12 : 285 to 340
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Error termsError terms Principle term is tomographic reconstruction Principle term is tomographic reconstruction
errorerror 30” radius means metapupils at highest turbulent 30” radius means metapupils at highest turbulent
layer are almost completely separatedlayer are almost completely separated 30” is still pretty small to find a 4-star mv = 12 30” is still pretty small to find a 4-star mv = 12
asterismasterism Have identified several suitable targets within a Have identified several suitable targets within a
2.5’ diameter FOV observable between June-2.5’ diameter FOV observable between June-October October
Will be even worse with the 10km Rayleigh LGS Will be even worse with the 10km Rayleigh LGS at Phases B and Cat Phases B and C
Requires the external turbulence profiling to Requires the external turbulence profiling to determine how much of the turbulence is above determine how much of the turbulence is above the LGSthe LGS
The Truth Sensor will be used as the principle The Truth Sensor will be used as the principle system diagnosticsystem diagnostic
Science camera can be used when the Science camera can be used when the turbulence cooperatesturbulence cooperates
>60% turbulence in the ground layer is often >60% turbulence in the ground layer is often observed at the WHTobserved at the WHT
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
System CalibrationSystem Calibration
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Phase A calibrationPhase A calibration Interaction matrix measurement using a Interaction matrix measurement using a
reverse path calibration sourcereverse path calibration source On-axis point source pointing backwards at On-axis point source pointing backwards at
output focal plane can be observed by each output focal plane can be observed by each NGS WFS in turnNGS WFS in turn
Requires stable pupil image at lenslet array Requires stable pupil image at lenslet array across full FOVacross full FOV
Or use TS to measure DM influence functions Or use TS to measure DM influence functions Observe ground-layer only turbulent sources Observe ground-layer only turbulent sources
within the telescope simulator with NGS WFSs within the telescope simulator with NGS WFSs and TSand TS
Translate TS measure influence functions to Translate TS measure influence functions to each DMeach DM
Or measure matrices on-skyOr measure matrices on-sky Learn and Apply method from Fabrice Vidal first Learn and Apply method from Fabrice Vidal first
thing this morningthing this morning
From telescope
From reverse path calibration source
ToWFS
NGS WFS pickoff prism
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
Other calibration tasksOther calibration tasks
Field dependent aberrationsField dependent aberrations Pupil image stability is <1/100Pupil image stability is <1/100 thth pupil diameter pupil diameter Monitoring and compensation changing field aberrationsMonitoring and compensation changing field aberrations
Non-common path error compensationNon-common path error compensation Deployable point sources in most focal planesDeployable point sources in most focal planes Some pointing backwards for reverse path calibrationSome pointing backwards for reverse path calibration
WFS linearity/gain optimisation (for WCOG etc.)WFS linearity/gain optimisation (for WCOG etc.) Use sources in NGS focal planeUse sources in NGS focal plane
NGS pickoff positioning accuracyNGS pickoff positioning accuracy Confirm with full field acquisition cameraConfirm with full field acquisition camera
Detector calibrationDetector calibration At Phase B/C:At Phase B/C:
LGS WFS offsets/centroid gainLGS WFS offsets/centroid gain Range gate setting and optimisation Range gate setting and optimisation LGS WFS interaction matrixLGS WFS interaction matrix
To be developed further during the Integration and Testing phaseTo be developed further during the Integration and Testing phase Runs from October 09 – April 10Runs from October 09 – April 10
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
ConclusionsConclusions
Already answered some of the big questions that MOAO Already answered some of the big questions that MOAO with EAGLE raiseswith EAGLE raises
Open-loop DM controlOpen-loop DM control Several calibration schemes proposedSeveral calibration schemes proposed
CANARY will have the capability to answer the CANARY will have the capability to answer the remaining ones by demonstrating and testing wide-field remaining ones by demonstrating and testing wide-field LGS tomographic AOLGS tomographic AO
Critical subsystems are being testing and the initial Critical subsystems are being testing and the initial integration phase is about to beginintegration phase is about to begin
We’re on track to go on-sky mid 2010 with the Phase A We’re on track to go on-sky mid 2010 with the Phase A NGS tomography experimentNGS tomography experiment
Phase B design to be reviewed at the end of this yearPhase B design to be reviewed at the end of this year
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
The CANARY teamThe CANARY teamDurhamDurham Richard Myers, Gordon Talbot, Nigel Dipper, Deli Geng, Eddy Richard Myers, Gordon Talbot, Nigel Dipper, Deli Geng, Eddy
Younger, Alastair Basden, Colin Dunlop, Nik Looker, Jonny Younger, Alastair Basden, Colin Dunlop, Nik Looker, Jonny Taylor, Mark Harrison, Tim Butterley, Dani Guzman, Laura Taylor, Mark Harrison, Tim Butterley, Dani Guzman, Laura Young, Simon Blake, Sofia DimoudiYoung, Simon Blake, Sofia Dimoudi
Obs. ParisObs. Paris Zoltán Hubert, Gerard Rousset, Eric Gendron, Fabrice Vidal, Zoltán Hubert, Gerard Rousset, Eric Gendron, Fabrice Vidal, Damien Gratadour, Aglae Kellerer, Michel Marteaud, Fanny Damien Gratadour, Aglae Kellerer, Michel Marteaud, Fanny Chemla, Phillipe LaporteChemla, Phillipe Laporte
UKATCUKATC Andy Longmore, David Henry, Stephen Todd, Colin Dickson, Andy Longmore, David Henry, Stephen Todd, Colin Dickson, Brian StobieBrian Stobie
ONERAONERA Thierry Fusco, Clelia Robert, Nicolas VedrenneThierry Fusco, Clelia Robert, Nicolas Vedrenne
INGING Jure SkvarcJure Skvarc
PUC SantiagoPUC Santiago Andres GuesalagaAndres Guesalaga
Herriott-WattHerriott-Watt Alan Greenaway, Heather DalgarnoAlan Greenaway, Heather Dalgarno
Engineering and Engineering and Project Solutions LtdProject Solutions Ltd
Kevin DeeKevin Dee
AO4ELTs, Paris 2009AO4ELTs, Paris 2009 CANARY: NGS/LGS MOAO demonstratorCANARY: NGS/LGS MOAO demonstrator Tim Morris et alTim Morris et al
CANARY capabilitiesCANARY capabilities
CANARY can:CANARY can: Perform, calibrate and characterise accuracy of open-loop LGS Perform, calibrate and characterise accuracy of open-loop LGS
tomography on-skytomography on-sky Measure/monitor everything to make sure we understand performance Measure/monitor everything to make sure we understand performance
of each component as well as the system as a wholeof each component as well as the system as a whole Develop alignment and calibration techniquesDevelop alignment and calibration techniques Combine several off-axis NGS and LGS WFSs to map the turbulence Combine several off-axis NGS and LGS WFSs to map the turbulence Eventually use a closed-loop woofer and open-loop tweeterEventually use a closed-loop woofer and open-loop tweeter Emulate arbitrary LGS intensity profiles and elongationEmulate arbitrary LGS intensity profiles and elongation
CANARY cannot:CANARY cannot: Reach EAGLE performance goalReach EAGLE performance goal Match the total number of subapertures/actuators within EAGLEMatch the total number of subapertures/actuators within EAGLE Match the exactly LGS/NGS FOV afforded by the E-ELTMatch the exactly LGS/NGS FOV afforded by the E-ELT Take advantage of the multiplex normally afforded by MOAO – only a Take advantage of the multiplex normally afforded by MOAO – only a
single channel single channel