Ritva Keski-Kuha

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JWST-PRES-012900
JWST OTE Development Status
Ritva Keski-Kuha JWST Deputy OTE Manager May 19,
2009
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Topics

• OTE Architecture Refresher
• Mirror Status
• Backplane Status
• IT Status
• Schedule
• Summary

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OTE Architecture Overview

• Aft Optics Subsystem (AOS)
• Fixed tertiary mirror
• Fine steering mirror
• Baffle and pupil mask

• SM Support Structure (SMSS)
• Deployable four-bar linkage strut assembly
• Secondary Mirror Mount (SMM)

• OTE Electronics Subsystem
• CMU Boxes
• CJB Box

• Thermal Management Subsystem (TMS)
• Panel Roof Radiators
• Panel /- V2 Radiators
• ISIM Enclosure (MLI)
• Parasitic Tray Radiator

• SM Assembly (SMA)
• Low mass Beryllium mirror
• 6 DoF pose control

• PM Segment Assembly (PMSA)
• 18 low mass Beryllium mirrors
• 6 DoF pose control
• Radius of curvature control

• PM Backplane Assembly (PMBA)
• Fixed Center Section supports 12 segments
• Two deployable wings support 3 segments each

• Deployable Tower Assembly
• Deployable telescoping tube
• Two deployable harness trays
• Cryocooler line accommodation

• TMS (continued)
• Deployable bat wings
• Fixed diagonal shield
• Deployable stray light bib

• Not Shown
• PMBA thermal management (SLI)
• WFSC Subsystem

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Three Mirror Anastigmat Optical Design Provides a
Wide Field-of-View
OTE
ISIM
V3 (anti-spacecraft)
(V1, V3)
origin
V2
V1
Tertiary
Mirror
Cassegrain
focus
Focal Surface
Fine Steering Mirror
Secondary mirror
f/ 20.0 Effective Focal Length 131.4 m PM
diameter 6.6 m (circumscribed circle)
Primary Mirror
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Mirror Status

• First Cryo test of Flight mirrors has been
  completed
• Hexapod performed well at cryo, cryo distortions
  of A1 and EDU at XRCF as expected.
• All PMSAs have completed grinding and are in the
  polishing and testing phase which includes
  fabrication at Tinsley, Integration and Test at
  Ball, Testing at the XRCF.
• The secondary mirror-1 was shipped from Tinsley
  to Ball. The mirror figure is below the
  specification.
• Tertiary mirror and Fine Steering Mirror making
  good progress at Ball.

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Completed 1st PMSA Tests at XRCF
Photo Credit MSFC
JWST_ISIM.May.MPR/1
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Cryotest 1 Summary

• First Cryo Conditioning Cycle,
• Mirrors taken to lt25K
• Measurements made at 28K

EDU
A1
Measurement Cycle
Cryo-Conditioning Cycle 2
Cryo-Conditioning Cycle 1
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Cryo-Deformation of EDU
EDU CRYO (Piston, Tilt, Power, Astigmatism,
Gravity Removed)
EDU AMBIENT (Piston, Tilt, Power, Astigmatism,
Gravity Removed)
Temperature 292K Dataset 7040.407AB
Temperature 29K Dataset 7040.410
MEASUREMENTS
RoC Change -18.997 mm
Cryo-Deformation (Piston, Tilt, Power Removed)
Total Cryo-deformation 142.7 nm rms
Astigmatism
Mid/Low Figure
High Freq Figure
RMS 115.4 nm rms
RMS 82.0 nm rms
RMS 25.0 nm rms
DIFFERENCE
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Significant Accomplishments/StatusL-3 SSG-Tinsley
Pathfinder EDU
Flight
Flight
TM1
EDU
C7
B2
C6
C1
FSM
B8
B3
A1
SM1
LEGEND
Not at L-3 SSG-Tinsley
Even Slice
Figure Grind
Smooth Out Grind
Rough / Smooth Out Polish Interleave
Fine Figure Polish
Shipped to BATC
Cryo Null Figure
Final Optical Test
Delivered
Pathfinder
A6
A2
C5
C2
SM2
A5
A3
A4
B7
B5
C4
C3
As of 4/18/09
B6
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Secondary Mirror Assembly Progress
SM Hexapod ready for assembly to substrate
SM substrate
Ball SM Test Optics
Tinsley SM Test Optics
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Tertiary Mirror and Fine Steering Mirror
TM substrate and sub-bench
TM in optical test stand
TM testing
FSM in vibration testing
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Mirror Coating Preparation is Progressingat
QCI-Denton
Coating GSE being loaded into Chamber
New JWST Coating Chamber
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Structures Status

• Backplane making good progress at ATK
• Flight Center Section bonding in progress
• Pathfinder CS bonding going well
• Completed layup and cure of the first Pathfinder
  SMSS strut
• Completed SMM (Secondary Mirror Mount) CDA
  4/28/09
• Near term reviews
• SMSS/PMBA CDA August 2009
• DTA CDA August 2009
• PMBSS CDA September 2009

SMM
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Tube Billets and SMSS Pathfinder Strut
First SMSS Pathfinder Strut
Tube billet storage rack
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Pathfinder and Flight Backplane Assembly
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I T Status

• Completed CDA for majority of the SSDIF Alignment
  and Integration Hardware and JSC Test Hardware.
• Null lens optics have been ordered
• ACF1 Skip Test execution starting in November
  2009
• ACF Mirror Blanks are in procurement
• Chamber isolator demonstration is in progress.
• PIT Review scheduled for July 2009

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Ambient Assembly Stand
Assembly Support Structures
Optics Integration Gantry System
V1-down Configuration
HP Struts
V1-up Configuration
HP Struts
Ambient OTE Assembly Stand Hardpoint Struts
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Test GSE Architecture and Subsystems
N

• Center of Curvature Optical Assembly (COCOA)
• COCI (MWL interferometer, null, calibration
  equipment)

• Isolation System

• Autocollimating Flat Mirrors (ACF Assembly)
• 3 ACFs (actuated motion)

• Down Rods
• Upper Suspension Frame (USF)
• Telescope Tension Rods

• Rogue Path
• Cryo Position Metrology
• Fiber fed PM Lights

LN2 and Helium Cryogenic Shrouds

• Space Vehicle Thermal Simulator (SVTS) by NG
• Hardpoint Offloader Support System (HOSS)

Optical Telescope Element (OTE Integrated
Science Instrument Assembly (ISIM) (OTIS)
E
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Architecture Layout
Ref. - JSC Chamber A
Ref. - OTIS and Thermal Sim(s).
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NGST OTE Intermediate Schedule
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Summary

• First Cryo test of Flight mirrors has been
  completed
• All PMSAs have completed grinding and are in the
  polishing and testing phase which includes
  fabrication at Tinsley, Integration and Test at
  Ball, Testing at the XRCF
• The flight backplane fabrication is in progress
• CDA for the majority of the SSDIF Alignment and
  Integration Hardware and JSC Test Hardware has
  been completed
• OTE CDA Scheduled for October 2009