1. MARS Design Review PP-1 Requirements Definition Performance: –Tip/Tilt error < 0.06″ rms mirror coordinates 0.12″ rms image coodinates 0.28″ fwhm image coordinates –Stacking Time < 10minutes requirement 5minute goal Operational: –Ease of Use –Ease of Maintenance –Full documentation

2. MARS Design Review PP-2 MARS Overview

3. MARS Design Review PP-3 Reference Pupil

4. MARS Design Review PP-4 Reference Spots

5. MARS Design Review PP-5 HET aligned

6. MARS Design Review PP-6 Current Stacking Performance Typically stop stacking when the largest mirror move is < 0.06″.

7. MARS Design Review PP-7 Causes of Poor Stacks Inconsistent Segment Capture –Inscrutable rejection parameters –Poor Segment Figure, 16% of segments have double lobes –Poor placement of pupil plane Poor Dome Seeing –Expands Stack –Makes Focusing difficult Improperly Set GroC

8. MARS Design Review PP-8 Pupil Plane Errors Affects Capturability Absolute Tip/Tilt accuracy

9. MARS Design Review PP-9 MARS II / MARS I Better camera –More pixels –More dynamic range –Analog/Digital operation Software enhancement –Integrated system –Improve segment capture/rejection algorithms More robust mounts with more precisely controllable degrees of freedom. Remote operation –Light source –Knife edge –Pitch and Yaw.

10. MARS Design Review PP-10 35mm Collimator Design 747:1 demagnification of primary to 14.7mm pupil image Tip/Tilt Angles Magnified by 747 Camera –Pulnix TM-1040: 1024x1024, 9μm pix, 10bit, 30Hz Camera Relay Lens –Telecentric, mag of 0.55 to fit pupil on chip For 5″ capture range tilt is magnified to 18.1mrad Max displacement with spots under lenslets 535μm Lenslet Focal Length 29.5 mm Collimator/Lenslet mag 0.6 Spot size required for Nyquist sampling 57mm Pixel subtends –0.55 mrad at the lenslet image plane –0.153″ on sky Resolution assuming 1/10pix centroiding –0.015″

11. MARS Design Review PP-11 Optional Optical Parameters Coll foc len Pupil size Lenslet size Relay mag Lenslet foc len Lenslet f ratio 28mm (5″ cap)11.7721.070.718.88f/17.6 (7″ cap)13.49f/12.6 35mm (5″ cap)14.7151.338.5529.52f/22 (7″ cap)21.09f/15 50mm (5″ cap)21.0211.911.460.25f/31.5 (7″ cap)43.04f/22 CapturePinhole Size Resolution 1/10 pix (7″ cap)81.5.021 (5″ cap)58.2.015 (1.3″ cap)15.004 * *

12. MARS Design Review PP-12 Current Stacking time Find Stack (use SenSys), Align M43 (tip/tilt) 3-5 min Measure Stack Size ** 3-5 min Focus (Knife Edge) 2-12 min Adjust GroC (PMC allfile) 0-5 min Log Conditions ** 1 min Measure Single Mirror (M54) ** 3-5 min Wavescope stacking: 10 min –Measure lenslet centers 15sec 15sec –Stack iteration 44sec x 6 264sec »Measure+Com ~ 25sec –PMC 32sec x 6 192sec –Slew 40sec x 2 80sec –Overhead ~60sec Place missed segments by hand with PMC 0-3 min Log Conditions ** 1 min PMC (MARS to SAMS), Set SAMS reference (35sec) 1 min Measure Stack Size ** 3-5 min

13. MARS Design Review PP-13 Stacking Time Total time 27-53 min Total time - IQ/logging 16-36 min

14. MARS Design Review PP-14 Where to save time No or Sparse SenSys IQ testing, Automate Logging 10min –Develop IQ measure from MARS Setup 1-2 min –Predict Tower/Stack position Focus 1 min –Better dome seeing will eliminate extended times –Automation will help Wavescope Stacking 6.5 min –Maximum 4 iterations, 1 slew 3min 12sec –Faster Computer/Code efficiency 10secx4 40sec –PMC (5sec update) 1min 48sec –Overhead 50sec Integration ? Minimum time 6.5 min

15. MARS Design Review PP-15 Operations Scenario Initial Setup (Ops at start of night) –Move Telescope to CCAS position –Move Tracker to nominal stacking position –Ops should set SAMS reference for the opening TEMP. Position MARS with respect to the HET (3min) –Move X, Y stages to align the MARS bore-site with that of the HET. X and Y positions are positioned by placing M43 on the reference spot. Yaw and pitch ?? –Move Z stage to set MARS to the best nominal GRoC. Focus on a segment apply any necessary offset. Stacking (3.5min) –Adjust GroC (allout through PMC, dihedral through SAMS) –Run Stacking code through 2 iterations –Move tracker –Run Stacking code through 2 iterations

16. MARS Design Review PP-16 Conclusions We are modeling MARS II on a relatively robust system which is now delivering to the stacking performance specifications most of the time. Time specifications are attainable, but will require : –Minimal follow-up measurements, –Reliably good dome seeing, –Faster PMC updates, –More reliable mirror capture, –Accurate placement in a maximum of 2 stacking iterations Need to tolerance the system to optimize operations.