1. SDO Deployment System Mission PDR
Jason H. Hair – SDO Deployment System Lead
Suk Yoon – Detail Designer
Jeanne Palmer – HGADS Structural Analyst
Steve Chaykovsky – SADS Structural Analyst
David Steinfeld – Thermal Analyst
Ben Rodini – Composite Consultant

2. Agenda Driving Requirements Design Implementation Requirement Status
Work Status
PDR Peer Review Summary
Development Flow
Schedule
Conclusion

3. Driving Requirements – Deployables
Launch Environment
Deployables shall survive the launch vibration, pressure, and load environment
SADS, HGADS shall have a stowed natural frequency > 35 Hz
Orbit Environment
SADS grounded to exterior of S/C > 10 m with 5:1 length:width strap
Deployables shall facilitate S/C surface charge dissipation
All external surfaces > 6 cm2 shall be conductive to <1E9 Ohms/sq
Deployment
SADS, HGADS Deployed frequency shall be > 2 Hz
Deployed systems shall withstand a max. acceleration of 0.04 g’s
Function
HGADS, SADS shall deploy so 2 HGAs combined have continuous clear FOV to ground
SADS shall provide 7.16 m2 (7.67m2 total area) mounting surface for solar cells
HGADS must accommodate RF waveguide from S/C to Antenna
Mass
SADS mass shall not exceed 42 kg total, HGADS mass shall not exceed 30 kg total
In the back-up section, all of my level II requirements for your reference.
However, I have pulled out my driving requirements for discussion
First are the driving requirements that effect both deployable systems,
Include Launch, Orbit Environments, Deployment Reqs, Contamination
Launch Environ. Defines stowed volume and for most part max. loads
Deployments must be successful in the event of max tip off rates.
From Orbital environment, we understand that must survive launch environment and operate in GTO and GEO
All the external surfaces must be conductive
Deployment must occur in while in GTO for S/A to provide power after sun acquisition
Deployables must withstand max thruster accel of 0.5m/s2, sizing impacts
General design standard of 4:1 torque ratio

4. Design Changes Since SCR
S/A Size Increase
Affected substrate geometry and HGA FOV
Release System Redesign
Kevlar – Thermal Knife S/A release discarded
SADS – HGADS linked release system scrapped
Actuator selection trade completed: QWKNUT
Release mechanism designed around QWKNUT
SCR S/A Restraint
Kevlar cable
SCR S/A Release
Thermal Knife cuts
cable for release
SCR Solar Arrays
Size, 6m2, driven by cell area

5. Design Implementation – Overall
SADS: Hinges, S/A Substrate, Release Mechanism
HGADS: Hinge, Boom, Release Mechanism, Waveguide
Deployed Solar Array
Deploy directly after LV Sep.
Deploy 90° to Sun Line
Symmetric, Fixed
S/A Shape
Driven by FOV
Optimize boom length
Deployed HGADS
Deploy once Power +
Position on S/C driven by FOV
Deploy 90° to x axis
2x for Reliability
Release System
All Independent
Redundant Mechanism
SMA QWKNUT actuators
Stowed HGADS
Fold 90o for launch
Stowed Solar Arrays
Fold 90o for launch
Boom Length
- Driven by HGA FOV

6. Design Implementation – Deployment
Solar Array Deployment
Driven by Torsion Springs
Controlled by Viscous Dampers
Monitored by POTs
Stowed System
After LV Sep
Solar Array Release
Redundant mechanism
Dual SMA QWKNUT actuators
Release directly after LV Sep.
HGA Release
2 Restraint Points
Redundant mechanisms
Dual SMA QWKNUT actuators
Planned release within first day
HGA Deployment
Driven by Negator Springs
Controlled by Viscous Dampers
Monitored by POTs

7. Design Implementation – SADS
Deployed Position
Panel edge even w/ S/C edge
Cell – Structure distance
Solar Array Substrate
7.67m2 total area
7.16m2 available for cells
Composite Facesheets
Al honeycomb core
Hinges
Interface w/ S/C top deck
2 per hinge line
Slave Hinge
- No damper/POT
Wire Harness
Routing
Stowed SADS
Snubber
Release Latch
- Interface w/ S/C
Restraint Latch
Pin Retractor
Snubber
Rotating Lug
(Al)
Main Hinge
- Damper/POT
Torsion Spring
- 21 in-lbs
3.0 in
Damper Flex
Coupling
POT
Damper
- DEB 1080
POT Flex
Coupling
Latch Arm
Assembly
Spherical Mono-Ball
Bearing
Spring Torque Wheel

8. Design Implementation – HGADS
Gimbal System
Boom
- Length for El CL 60in from S/C
Antenna
Deployment Hinge
- 90° Travel
Snubbers
Release Latches
One component preload type
One V-Guide
DEPLOYED HINGE
Negator Spring
58 in-lbs, 4 leafs
POT
Latch Arm
Prop
Module I/F
Boom
Release Latch
on S/C
Waveguide I/F
to Prop Module
(Flex)
Hole for
Waveguide
Stowed HGADS
on S/C
Rotary
Joint
7.25 in
Hinge
- Interface w/ Prop Module
Damper
Deploy to Stop
- Spring holds on stop
Wire Wrap
Drum
Underside of Prop Module

9. Design Implementation – Release Latch
Sphere Pin to S/A or HGA
Sphere on Sphere I/F
I/F for V-Guides
Latch Arm
QWKNUT
QWKNUT
Backing Plate
¼-28 Nut
Oversize
Washer
Torsion
Springs
For Latch
Arms
Hex
Flats
Plunger pre-loads
on backing plate
Viton
Washer
Latch Arms
Rotate
QWKNUT
Releases
Plunger
Sphere Pin pulled
up by Retractor
Plunger pulled
against Stop by
Latch Arm Spring
Plunger drives out
from pre-load energy,
spring on Latch Arm
Vespel
Bushing
Viton Hits
Hard Stop

10. Requirements Status
HGA Gimbal Actuator loads below allowables with margin
Stowed Frequencies
HGADS Stowed Frequency: 58 Hz (35 Hz req.)
SADS Stowed Frequency: 37 Hz (35 Hz req.)
Deployed Frequencies
HGADS Deployed Frequency: 2.7 Hz (2 Hz req.)
SADS Deployed Frequency: Hz (2 Hz req.)
Stowed Constraint Loads
Constraint snubber loads < 500 lbs
Release latch preload required < 2500 lbs
Accommodation
HGADS FOV is 6 months coverage per HGA
Required 130 strings fit on S/A substrate
Optimized HGA Config
Taper solar arrays
Optimized boom length
Provides clear HGA FOV

11. Requirements Status Mass Torque Margin Deployment Time Deployed Loads
HGADS mass: 28kg for 7% margin on 30kg req.
SADS mass: 39kg for 7% margin on 42kg req.
Suballocation of mechanical subsystem.
Torque Margin
HGADS available torque 58 in-lbs => 4.2:1 torque margin
SADS available torque 42 in-lbs => 6.1:1 torque margin
Deployment Time
HGADS with a damping ratio of 1000 in-lb-sec/rad => 42 sec.
SADS with a damping ratio of 500 in-lb-sec/rad => 18 sec.
Deployed Loads
Deployment lock-in: SADS – 180 in-lbs, HGADS – 290 in-lbs
Main engine thrust loads: SADS – 75 in-lbs, HGADS – 110 in-lbs
Operational ACS loads: SADS – 10 in-lbs, HGADS – 20 in-lbs
Pointing
HGADS thermal distortions 0.003° for good margin on 0.01° requirement
S/A positioned such that cells at least 4° from S/C or Instruments

12. Work Status Documents Design Analysis
Deployment System Requirements Doc. (464-MECH-SPEC-0005) submitted to CM
Design
Preliminary design complete, continuing to increase detail
Analysis
Overall analysis shows design meets requirements with margin
Continuing on to in-depth analysis
Development Unit Fabrication Started
Release mechanism will be first complete
Units for HGADS hinge and SADS hinges to be made
Trade Studies Completed and Documented
HGADS constraint point selection
Release actuator and mechanism selection trade
HGADS hinge rotary joint location

13. PDR Peer Review Summary
Deployment System PDR Peer Review, Nov 3, 2003
Total of 29 RFAs assigned, All 29 Closed
Major Issues Addressed
Document decision to select QWKNUTs for release mechanism
Documented Trade Study completed during selection process, 464-MECH-TRD-0022
Consider improving internal loading condition in release mechanism
Altered release mechanism to straighten load lines to reduce internal loads, 464-MECH-REVW-0068
Evaluate moving HGADS hinge rotary joint outside hinge
Conducted Trade Study and decided to keep RJ inside hinge for thermal reasons, since reqs met
Other PDR Peer Reviews participated in
HGAS PDR Peer Review #1, Aug 7, 2003
HGAS PDR Peer Review #2, Nov 17, 2003
Mechanical System PDR Peer Review, Dec 15, 2003
Total of 9 RFAs assigned, 5 Closed, 4 Pending Closure with Responses

14. Flight Design, Analysis Structural Verification
Development Flow
Development Philosophy: ProtoFlight with precursor Development Units
Take advantage of Mechanical Structural Verification Unit
Flight Design, Analysis
Concept
Design,
Analysis
Development
Unit
Test
Detail
Design,
Analysis
Proto Flight
Unit
Fab, Procure
Component
Testing
Structural Verification
Deploy
Functional
Testing
Environ.
Testing
(SVU)
Thermal
Vacuum
Funct Test
Deliver to
Next Level
Integration

15. Verification Tests

16. Deployables Development
Schedule
Subsystem & Element
CY 2003
CY 2004
CY 2005
CY 2006
CY 2007
CY 2008 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
4/8
5/03
3/4
2/05
4/08
MISSION MILESTONES
SCR
ICR
PDR
CDR
LAUNCH
Deployables Development
Dev. Fab/Test
1 = Spacecraft Integration
= Schedule Reserve
2 = Instrument Integration
3 = Environmental Testing
4 = Launch Site Operations
SADS
Design
Procure
Fab
Proto FLT Assy
Integrate S/C ETU
Verification Test
Del Substrate to Cell Vendor
Receive FLT Arrays
FLT Array Assy
Deliver to I&T
HGADS
Design
Procure
Fab
Proto FLT Assy
Integrate S/C ETU
Verification Test
Deliver to I&T
Verification Testing
Integration of Verification Unit
Verification Testing
Spacecraft I&T 1 2 3 4
Launch

17. Conclusion Preliminary Designs satisfy functional requirements
Current designs satisfy functional requirements
Analysis shows design technically feasible with margin
Further analytical work to ensure satisfaction of detailed requirements remains
No major complications anticipated, requirements are standard for system type
Designs within cost, schedule constraints
Looking forward to developing the next level of detail on road to CDR