Mechanical Design

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Mechanical Design
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Mechanical Design Status

• Progress in all areas since CoDR.

• Most analysis is complete.
• Grating turret stiffness ?
• OIWFS gimbal mount stiffness (Budget)?

• Fine detailing of solid models to be completed.
• Duplicate Focal Plane Mask Wheel for Filter
  Wheel.
• Screws, washers, etc.

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NIFS Integration
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Handling the Cryostat
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Components on the OIWFS side of the Cold Work
Surface.
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View of OIWFS
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Helium Cryocooler Cold Straps
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OIWFS Assembly
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Shack-Hartmann Optics
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Two Facet Prism
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Focal Plane Unit
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Pick-Off Probe Guide Field
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Focal Plane Unit Components
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Focal Plane Mask Wheel
Motor full step moves mask 1/200 arcsec.
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F/Converter Cold Stop
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Pupil Baffling
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Components on the Spectrograph side of the Cold
Work Surface.
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Spectrograph Housing
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Spectrograph Components
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Housing Stiffness

• All towers bolt between CWS and Cover.
• Skirt bolts between CWS and Cover to form
  structure with 250 nm deflection.

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Modules and Towers
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Filter-Fold Tower
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Fold Mirrors
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Tri-Fold Tower
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Tri-Fold Mirror
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Pupil Field Mirrors
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Pupil Array Machining
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Mirror Array Flexure

• Deflection under self load lt 300 nm (0.01 pixels
  at detector).
• Natural frequency 1000 Hz.

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Image Slicer Assembly
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Image Slicer Stack
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Slicer Fanning Axis
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Slicer Machining
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Bouwers Collimator Tower
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Bouwers Corrector Tower
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Grating Assembly
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Turret Shaft Flexure
Cantilevered 50 mm Dia. Deflection 0.000 3 mm
Cantilevered 25 mm Dia. Deflection 0.004 mm
Simply Supported 40 mm Deflection 0.000 06 mm
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Grating Drive System

• One motor step moves spectra one pixel on
  detector.
• On-axis drag brake locks turret.

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Grating Mount System
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Grating Drive Sectioned
Dynamic Overshoot 0.3 Pixels, Setting Error 0.03
Pixels
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Grating Drive Train
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Flip Mirror Assembly
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Spectrograph Baffling
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Baffle Evaluation
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Baffle Evaluation
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Spectrograph Camera
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Spectrograph Camera
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Detector Assembly
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Detector Circuit Card
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Detector Cabling
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Detector Cabling
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Detector Thermal
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Detector Thermal
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Detector Safe Handling
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Detector Service in Frame
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Spectrograph Alignment
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Cold Stop Alignment
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Image Slicer Alignment
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Grating Pupil Alignment
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The End
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Non-Common Path Phase Errors
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NIFS plus ALTAIR

• Artificial star from ALTAIR
• Differential flexure comparison
• Phase Maps, common path optics in NIFS

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• NIFS common path optics.
• Telescope focus -30mm to fill 2mm entrance
  aperture.
• Common path optics near focus see large changes
  in footprint.

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• Phase maps from NIFS will be small.
• We can make phase maps by warming the cryostat
  and moving the detector about -9mm. Our manual
  focusser is designed for about -3mm.