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

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

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

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

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

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

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

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

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

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: 2.13 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

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

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

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

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

Verification Tests

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

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