The Instrument: US Subsystems and Requirements

1
The Instrument US Subsystems and Requirements

• Dr. Clarence M. Korendyke
• US Project Scientist
• Naval Research Laboratory
• 202-767-3144
• e-mail koren_at_cyclops.nrl.navy.mil

Dr. Charles M. Brown EIS US Instrument
Scientist Naval Research Laboratory 202-767-3578 e
-mail cbrown_at_ssd5.nrl.navy.mil
2
EIS Optical-Mechanical Layout
Plan View
Elevation
3
MIR/SLA/GRA Electrical Interfaces
4
Lifecycle Requirements
5
Articulated Telescope Mirror (MIR) Requirements

• Mount the Optic With Minimal Distortion Over the
  Applicable Temperature Range
• Tilt the Optic to Move the Solar Image (4)
  Perpendicular to the Slit
• Sense the Relative Position of the Optic Tilt
  With lt1 Arcsec Accuracy
• Translate the Optic 8 mm Perpendicular to the
  Optical Axis
• Sense the Position of the Optic to lt20 Microns

6
MIR Hardware Description/Summary
Linear Ball Slide
Flexpivot
Translation Motor and Drive Assy
Mirror
PZT
7
Focussing Grating (GRA) Requirements

• The GRA Shall Mount the Grating With Minimal
  Distortion Over the Operational Temperature Range
• The GRA Shall Provide a Focussing Capability of
  1 cm to Permit Adjustment of the Spectrometer
  Focus
• The EIS Grating Will Be Bonded Into a Cell
  Mounted Onto a Crossed Roller Slide Translation
  Stage
• Translation Stage Will Be Driven With a Geared
  Stepper Motor and Ball Screw Combination. The
  Mechanism Will Be Operated in Open Loop Mode. The
  Position Will Be Sensed With Optical Encoders

8
GRA Hardware Description/Summary
Grating
Motor and Ball Screw Assy
Crossed Roller Bearing Slide
9
Slit Assembly (SLA) Requirements

• The SLA Shall Support the Shutter Assembly
• The SLA Shall Be Able to Position the
  Spectrometer Slits and Slots to Be Reproducible
  in the Telescope Focal Plane
• The Spectrometer Slits Shall Be Reproducibly
  Positioned to lt2 Microns Perpendicular to the
  Optical Axis and lt26 Microns Along the Optical
  Axis. A Performance Goal for the Mechanism Will
  Be lt1 and lt13 Microns, Respectively
• Positioning Will Be Accomplished Using a Geared
  Stepper Motor With the Direction of Motion Along
  the Optical Axis

10
Slit Assembly (SLA) Requirements (Continued)

• The Load Position Will Be Sensed Utilizing a
  Shaft Resolver
• The Present Optical Design Does Not Permit the
  Resolver to Be Directly Attached to the End of
  the Shaft, and the Resolver Is Instead Coupled to
  the Output Shaft With Anti-backlash Gearing This
  Approach Should Suffice to Meet Specified Goals.
  The Backlash Inherent in the System Is Expected
  to Be 3 Arcminutes With a 15 Arcminute Step
  Size. This Corresponds to an Uncertainty of 10
  Microns in the Position of the Slit Along the
  Optical Axis With a 50 Micron Step Size
• The Resolver Will Have an Absolute Accuracy of
  lt15 Arcminutes Sufficient to Discriminate Between
  Individual Steps

11
SLA Hardware Description/Summary
Shutter Motor and Encoder
Shutter
Slit Paddle Wheel
Slit Motor and Encoder
12
Shutter Mechanism Requirements

• The SLA Shall Include the EIS Instrument Shutter
• The Shutter Shall Be Able to Take a 50 ms
  Exposure
• lt5 Photometric Error Over the Slit for These
  Short Exposures

13
Shutter Assembly Hardware Description/Summary
14
Requirements for the Filter Clamshell

• Vacuum Tight Enclosure
• P lt1 Torr for Launch TBD 140 dB Acoustic Loads
  Expected
• Hold Time gt1 Week TBD
• Reliable Calibrated Internal Pressure Sensor
• Clean
• Minimal Central Obstruction
• Pumpout/Backfill Valve With Filter and Throttle
• No Pressure Differential Allowed Front/Back (Air
  Passages)
• Sunshade for Filter Frame
• No Shock on Opening
• Vacuum Harness for Pre-Launch Ops

15
Front Filter Assembly (FFA) Requirements

• A FFA Shall Be Provided to Block Heat and Visible
  Light From the EIS Instrument
• The FFA Shall Also Serve As a Bandpass Filter for
  the EUV Range of Interest
• The Filter Will Consist of a 1500 Å Thick
  Aluminum Film Mounted on a Nickel Mesh. The
  Aluminum May Be Coated With a Few Å of Carbon to
  Reduce Oxidation and to Improve Rejection of
  Light in Unwanted Solar Lines
• The FFA Will Provide a 1 Transmittance
  Uniformity
• The FFA Shall Be Compatible With Ultra High
  Vacuum (UHV), and It Shall Provide the Necessary
  Mechanical Strength, and the Capability to
  Withstand Torr-Level Pressure Differentials

16
Front Filter Assembly (FFA) Requirements
(Continued)

• The Front Filter Will Be a 200 mm Clear Aperture
  Diameter and It Will Be Segmented Into Four
  Quadrants, Each Separately Replaceable
• A Lightweight Aluminum Frame Shall Support the
  Mesh
• A Clamping Frame Shall Secure the Filters to the
  Clamshell Assembly. The Frames Will Be Designed
  to Minimize the Central Obstruction

17
Requirements for the Al Filters

• For the Entrance Filter
• lt1500 Å Al on Ni Mesh (gt80 Open)
• ? lt0.1
• T gt30 _at_ 304 Å
• T lt5 X 10-5 for Visible IR
• 20 cm Clear Aperture, in Quadrants
• For the Spectrometer Entrance Filter
• lt1500 Å Al on Ni Mesh (gt80 Open)
• T gt30 _at_ 304 Å
• T lt 5 X 10-7 for Visible IR
• 0.5 cm X 1.5 cm Rectangular

18
FFA Hardware Description/Summary
Quadrant of Trace Entrance Filter
19
Spectrometer Entrance Filter (SEF) Requirements

• A Small Diameter Aluminum Filter Shall Be
  Provided to Mount Behind the EIS Spectrometer
  Slit
• The SEF Shall Provide Additional Reduction of the
  Visible Light Within the Spectrometer, Especially
  in the Event That the FFA Degrades Due to Orbital
  Debris and Micrometeorites
• The SEF Shall Have a Clear Aperture of 20 mm. It
  Shall Be Placed Near the Slit, but Far Enough
  Away (gt8 mm) That the Mesh Will Be Totally Out of
  Focus at the Detector
• Table 3-6 of the EIS Subsystems and Components
  Contract End Item Specification, EIS_Comp_Spec,
  Lists the Required Filter Properties

20
SEF Hardware Description/Summary
Luxel TF Aerospace Al filter
21
EIS Instrument Classification Mission
Classification
Recommended Guidelines for EIS Instrument
Components
22
Mission Analysis Approach
Independent Agent
Tailored to Meet Guidelines of EIS Instrument
Component Contract End Item (CEI) Specification
Recommended Approach for EIS Instrument Components
23
Safety, Reliability, and Quality Assurance
(SRQA) Requirements

• SRQA and Verification Compliance Matrix (VCM)
  Requirements Defined in EIS Instrument Component
  CEI Specification (EIS_comp_spec)
• Configuration Management Plan uses MSFC MPG
  8040.1Guidelines for Flight Models (DRD
  874CM-001)
• Contamination Control Implementation Plan in
  Consonance with UKs EIS Instrument Requirements
  (DRD 872MP-001)
• Product Assurance Program for Flight Models Meets
  ISO 9000 Guidelines (DRD 872QE-001)
• Includes Preliminary/Final Hazard Analysis Inputs
  to UKs EIS Instrument Safety Plan
• Includes Reliability Assurance and
  Parts/Materials/Processes Approach
• Verification Plan Defines Verification Approach,
  Structure, and Description (DRD 872VR-001)

24
Other Factors

• Parts, Materials, and Processes (PMP) Selected to
  Assure Maximum Reliability and Performance in
  Space Environments
• Vacuum Stability via Total Mass Loss (TML) of
  gt1.0 and Volatile Condensable Material (VCM) of
  gt0.1 Per NRP-1124
• Traceability Achieved by Categorizing EEE Parts
  Into Sets Groups and Tracing Parts Through
  Fabrication, Assembly, Test, and Delivery
• Electrostatic Discharge (ESD) Control According
  to Processes Implementing MIL-STD-1686 Guidelines
• Closed-Loop Failure Reporting and Corrective
  Action System (FRACAS) for Failures Occurring
  During the Flight Model Acceptance Testing Phases
• Deliverable Shipping Container Compatible With
  the Anticipated Transportation Environmentals
• Documentation Uses Established Practices for
  Spaceflight Equipment
• Deliverable As-built Engineering Drawings for
  Flight Models
• Schematics, Assembly Drawings, Parts Lists, Test
  Procedures/Reports, and Calibration Data

25
Project Planning and Control (1 of 3)

• During Phase B, the Following Management Tools
  (Delivery Dates) Will Be Developed to Allow
  Adequate Definition of the Hardware, Services,
  Materials, Subcontracts and Other Services of the
  Project
• Configuration Management Plan (31 December 1999)
• EIS Component Specification Contract End Item
  (Updates A/R Under Configuration Management)
• Preliminary Design Review Package (15 February
  2000)
• Interface Control Documents (15 February 2000)
• Project Management Plan (31 December 1999)
• Monthly Progress Reports (Monthly)

26
Project Planning and Control (2 of 3)

• Phase B Management Tools Continued
• Financial Management Reports (Monthly)
• Work Breakdown Structure and Dictionary (30
  November 1999)
• Risk Management Plan (31 December 1999)
• Contamination Control and Implementation Plan (15
  February 2000)
• Product Assurance Plan (31 December 1999)
• System Error Budget (15 February 2000)
• Verification Plan (31 December 1999)

27
Project Planning and Control (3 of 3)

• During Phase C/D, the Following Management Tools
  (Delivery Dates) Will Be Developed to Allow
  Adequate Definition of the Hardware, Services,
  Materials, Subcontracts and Other Services of the
  Project
• All Management Tools Developed Under Phase B
  Shall Be Updated As Necessary
• Critical Design Review Package (15 February 2001)
• Pre-Environmental Review Package (15 February
  2002)
• Flight Readiness Review Package (15 September
  2002)
• Verification Test Report (15 September 2002)

28
Product Assurance

• EIS Instrument Component Product Assurance
  Guidelines Shall Be Defined in the Product
  Assurance Plan Submitted During Phase B
• The Product Assurance Plan Shall Address
• Safety Implementation of Industrial and System
  Safety Throughout the Project Lifecycle
• Quality Implementation of All Elements of the
  Quality Assurance Program Throughout the
  Lifecycle of the Project
• Reliability Definition of the Procedures and
  Controls for Implementing the Programmatic
  Reliability and Maintainability Requirements

29
EIS Instrument Component Work Breakdown Structure
(WBS)
30
EIS Instrument Component Schedule Summary