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X-ray Missions Delta: AXSIO Redux. Integration & Test Allen Crane Harvey Safren 30 April – 1 May, 2012. Redux Summary.
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X-ray Missions Delta:AXSIO Redux Integration & Test Allen Crane Harvey Safren 30 April – 1 May, 2012
Redux Summary • The impact of the delta’s on the I&T grassroots cost will be minimal. The only changes that might affect I&T appreciably are the reduction in mass of the XMS (~140 kg) and the elimination of the focusing mechanism. But the impact of these on cost will be quite small, resulting from a slight decrease in testing time, probably of just a few days at most. The reduction in cost would likely be less than the error in the grassroots cost estimate.
Integration and Test Summary Overall I&T Process & schedule considered and deemed viable Flexibility exists in Observatory testing to consider alt approaches Top Level I&T flow • Integration flow: • Spacecraft Bus I&T Subsystem I&T Functional, Vibe and Thermal test • Instrument Module integration XMS & XGS CCD integrated to Instrument Deck • Observatory integration FMA integrated to the S/C bus Metering Structure integrated to S/C bus, yielding the S/C Module Instrument Module integrated to S/C Module • Test flow: • Observatory functional and performance validation Completed in a thermal-vac chamber in a horizontal position • Observatory environmental testing EMI/EMC, vibration, acoustics and mass properties • Launch Site flow
AXSIO Program flowrevised from IXO RFI 2 - 8 3 09 Mission Critical Design Review (CDR) 6/11/2018 Phase B Start S/C Bus 12/14/2014 Preliminary Design Review (PDR) 12/12/2016 S/C Bus Contract Award System Definition Review (SDR) Project Start 12/13/2012 Phase A Preliminary Analysis Phase B Definition and Prelim Design Phase C Final Design Preliminary Design Mission Definition System Definition Final Design 24 months 24 months 18 months End of Extended Mission 6/15/2027 Funded Reserve 10/14/2021 Transition To Nominal Ops 7/15/2022 End of Primary Mission 6/15/2025 Instrument Delivery 3/24/2020 Launch 6/15/2022 Phase D-1 Subsystem Development, S/C Integration & Test, Launch Prep Phase E/F Operations Phase D-2 Launch & Checkout Funded Reserve Fab., S/C Assy & Func. I&T ~21 mo.s Prep for Launch ~3 mos Obser. I&T 16 mo.s Cruise, Orbit Insertion & Checkout PrimaryMission Reserve 8mo.s Launch & Checkout Extended Mission 48 months 9 month 1 month 3 mo.s 33 mo.s 24 mo.s Timeline not to scale
I&T MDL study process • Presentation & content predominately based on heritage from prior Con-X & IXO MDL studies • Integration flow changes • S/C Bus vibe and thermal with Metering Structure ETU and FMA & Instrument Module Mass Simulator added to buy down risk to Observatory level environmental test • FMA integration to S/C Bus moved before Metering Structure given current design requirement that FMA installs to the S/C Bus from the Metering Structure side • Test flow changes • MSFC XRCF baselined for pre Envir TVAC 1, Post Envir TVAC 2 / Tbal given the need for an X-ray source & vacuum envir • TVAC = Bake out (TVAC 1), Focus / Alignment, Calibration, CPT • Wyle Laboratory, Huntsville Al baselined for Observatory Envir Test to minimize transport (pending accommodation check) • Mission timeline • Developed from IXO RFI 2 (8 3 09) with input from MSE & PI
I&T Assumptions • Subsystems include: • Power: deployable solar arrays, battery (nonflight thru observatory testing) • Thermal: cryocoolers, radiators • ACS: Star Tracker, CSS's, RWA's, gyro, thrusters • Comm: fixed Ka and Omni S band antennae • Task durations: • Include transfer and prep/setup overhead • Are "success-oriented" and do not include margin/reserve • Payload and bus delivered to GSFC ready for "observatory" level I&T • Fully qualified per GEVS • No additional stand-alone testing required • Existing Goddard facilities sufficient for S/C Bus Envir test, but not optical testing • Test-specific assumptions: • Dry vibe • Wet thermal-vac • Thermal-vac includes radiators but no solar arrays • No jitter test or spin balance required • Some unique GSE required: • Electrical: ground test system, flatsat, spacecraft simulators • Mechanical: deployment test fixtures (g-negation), dollies, slings • Thermal: Cryo / heater panels, TCUs • Fluids: prop servicing, GN2 purge • Test conductors from Flight Ops Team; ¾-time for I&T support • Those who will be operating spacecraft during mission train during I&T
From NASA Procedural Requirements, NPR 8705.4, Appendix B Class A Missions (included for comparison with class B) Single Point Failures (SPFs) Critical SPFs (for Level 1 requirements) are not permitted unless authorized by formal waiver. Waiver approval of critical SPFs requires justification based on risk analysis and implementation of measures to mitigate risk. Engineering Model, Prototype, Flight, and Spare Hardware Engineering model hardware for new or modified designs. Separate prototype and flight model hardware. Full set of assembled and tested “flight spare” replacement units. Qualification, Acceptance, and Protoflight Test Program Full formal qualification and acceptance test programs and integrated end-to-end testing at all hardware and software levels. Class B Missions Single Point Failures (SPFs) Critical SPFs (for Level 1 requirements) may be permitted but are minimized and mitigated by use of high reliability parts and additional testing. Essential spacecraft functions and key instruments are typically fully redundant. Other hardware has partial redundancy and/or provisions for graceful degradation. Engineering Model, Prototype, Flight, and Spare Hardware Engineering model hardware for new or significantly modified designs. Protoflight hardware (in lieu of separate prototype and flight models) except where extensive qualification testing is anticipated. Spare (or refurbishable prototype) hardware as needed to avoid major program impact. Qualification, Acceptance, and Protoflight Test Program Formal qualification and acceptance test programs and integrated end-to-end testing at all hardware levels. May use a combination of qualification and protoflight hardware. Qualified software simulators used to verify software and system.
AXSIO Mission Timeline1 of 2 • Revisions from IXO RFI 2 - 8 3 09 • Phase A – 24 months = 2/3 of IXO 30 months (RFI 2 – 8 3 09) given the increased maturity of FMA design • Phase B – no change given that FMA facility development still required • Phase C – increased to 18 months from IXO 12 months which seems too short for project of this size • Phase D – 48 months reduced 6 months from IXO 54 months given: • 2 vs 5 instruments • less deployables (fixed metering structure) • easier FMA fab • Reserve average between 20% of Phase D and Gold Rule calculation
AXSIO Mission Timeline2 of 2 Revised from IXO RFI 2 - 8 3 09
Spacecraft Bus I&TTop-Level Flow Total: 33 weeks Integration • Notes: • Subsystems previously qualified prior to delivery (Bus Structure, Box Environmental) • -Task sequence for reference only; some tasks may be performed in parallel (e.g., harnessing, thermal) • Integration includes: mechanical integration, electrical safe-to-mate • Short functional test performed following each vibration (axis) test Environmental Testing & Pre-Delivery
Instrument Module I&TTop-Level Flow • Notes: • XMS & XGS Instruments previously qualified prior to delivery • - Task sequence for reference only; some tasks may be performed in parallel (e.g., harnessing, thermal) • - Integration includes: mechanical integration, electrical safe-to-mates
Observatory IntegrationTop-Level Flow • Notes: • - Spacecraft bus & instruments previously qualified prior to delivery for observatory integration • Task sequence for reference only; some tasks may be performed in parallel (harness, thermal h/w) • - Integration includes: mechanical integration, electrical safe-to-mates
Observatory TestTop-Level Flow TVAC 4 thermal cycles Notes: - Short functional test performed following each vibration (axis) test - Scope of testing appropriate to class B Mission
Launch Site OperationsTop level flow Payload Offline Processing Operations Hazardous Processing Facility Operations Integrated Vehicle & Pad Operations Total: 8.5 weeks + Vehicle Ops Notes: - Some tasks may not be contiguous, i.e., due to launch site scheduling or vehicle operations - Task sequence for reference only; some tasks may be performed in parallel (e.g., payload functionals)
Special GSE Required for I&T effort • X-ray point source GSE used to monitor contamination in optical path, especially FMA. Gives realistic measurement of science degradation, indicate contamination event • Electrical & Mechanical simulators: • S/C simulator for testing with the Instrument Module • Instrument simulator for testing with the S/C Bus • Metering Structure ETU for testing with S/C Bus • FMA mass simulator for testing with the S/C Bus • S/C Bus & Instrument Deck ETU for cold deployment testing
Issues/Concerns/Considerations1 of 2 I&T Timeline full bottom up review likely to revise down ETU vs Prototype testing trades needed S/C Bus Vibe & Thermal Test utility to buy down risk to Observatory testing Observatory Optical Testing • TVAC 1 scope could be reduced to just an ambient temp Focus / Calibration / LPT at vacuum • Save cost in test setup and thermal operations • Add risk from delay final focus confirmation • Vertical Optical test alternative would eliminate the design need to over-constrain the FMA mirror element required for horizontal testing. • The FMA over-constraint could introduce focus error. Additional mirror distortion analysis needed to ensure this is a viable path forward. • Would require development of a scanning point X-Ray source
Issues/Concerns/Considerations2 of 2 Test Facilities • GSFC integration facilities are sufficient to AXSIO needs, but some test limitations are noted • Existing GSFC Vibe cell door height 9m will not accept 11m height of AXSIO • New vibe cell planned for JWST in Bldg 29 high bay should accommodate AXSIO • GSFC SES 40ft height may be sufficient for Observatory optical test • 36.8ft AXSIO height allows X-Ray point source GSE 3.3 height allowance • Making overall test fit SES would provide significant program cost savings • A list of sufficiently large alternative thermal/vac chambers is given in next slide • MSFC XRCF identified as baseline optical / thermal test facility, but MSFC environmental test facilities cannot accommodate 11.2m x 3.3m diaObs • Looking into Wyle Laboratory capabilities local to MSFC • Alternative ship back to GSFC for Envir test
Alternative TVAC facilities • There are five thermal vacuum chambers in the US that are large enough to accommodate the AXSIO Observatory (which is approximately 39ft tall) in a vertical orientation, located above a GSE point scanning X-ray source • Arnold Engineering Development Center, Arnold AFB, Tullahoma, Tennessee; 42’ diameter by 82’ high (vertical) • NASA JPL, Pasadena, California; 27’ diameter by 85’ high (vertical) • NASA JSC, Houston, Texas; 65’ diameter by 120’ high (vertical) • NASA GRC, Plum Brook Station, Sandusky, Ohio; 100’ diameter by 122’ high (vertical) • Lockheed Martin Missiles and Space, Sunnyvale, California;40’ diameter by 80’ long (horizontal) Pressure 10-6 10,000 clean room Wet/dry mass ~3000 kg
Acknowledgements and Traceability • This file documents the current configuration of the Advanced X-ray Spectroscopic and Imaging Observatory (AXSIO) Integration & Test. • The subsystem design herein is predominantly based on the Integration & Test concept developed by Pat Kilroy and Harvey Safren, during the “IXO” Mission Study conducted at the NASA Goddard Space Flight Center’s Mission Design Lab (MDL) on the week of January 12-16, 2009 • The “IXO” Mission Study was based on the Integration & Test concept developed by Harvey Safren, during the “ConX-5” Mission Study conducted at NASA Goddard Space Flight Center’s Mission Design Lab (MDL) on the week of 2008 July 28. • The “ConX-5” MDL Study, in turn, was heavily based on the ConX Project’s “ConX Atlas V. 20m Single Mirror 3 Mast” mission concept and preliminary resource estimate.
I&T Objectives • Maintain a Safe Environment For I&T Personnel and Flight H/W • Maintain the Cleanliness Conditions for the AXSIO S/C & Instruments • Verify all Flight Mechanical and Electrical Interfaces • Develop and Verify Command and Telemetry Database, • All Commands and Telemetry Must be Exercised at Least Once • Perform Environmental Qualification of the AXSIO Observatory • Verify Observatory Performance Requirements are Met Throughout the Environmental Test Program, Including (to the extent possible) Instrument Performance in Thermal Vacuum • Verify Observatory Compatibility with AXSIO Mission Operations Systems • Make AXSIO Ready For Launch, assist in integration to launch vehicle.
I&T Program elements • I&T Flow • I&T Schedule • List of GSEs, Simulators, Test Languages, Main Procedures • Facilities, Floor Plan layouts, IT Networking • Manpower • Cost • Verification Matrices • Verification Method: T/A/I/D • Verification Level: F/PF/Q • Verification Unit: F/PF/ETU, etc. • Verification Philosophy • Test As You Fly ! • Verify each requirement at the highest level possible • Operation of an element is verified after integration into a higher level • Performance Verification and Environmental/Workmanship Verification • Models Philosophy • ETU’s, Breadboards, Brass boards, etc. • Heavy testing / qualification on Test Models, Brass boards, EM, Acceptance testing on Flight Models
Verification Program Overview • Establish confidence that the Mission will be a success • Verify: • Functional, Performance, and Operational Requirements • Requirements • Mission Level Functional, Performance, Interface, and Operational Requirements • Workmanship Standards • Materials Control • Quality Assurance
I&T Assumptions - Requirements1 of 4 • Flight hardware will be qualified per GSFC-STD-7000, the “General Environmental Verification Standard” (a.k.a. GEVS) dated April 2005. • All lower assembly level hardware structures, boxes & components through Module level will be fully qualified per GEVS at their level of assembly prior to delivery to observatory I&T, given any additions/exceptions. • The Goddard Open Learning Design (G.O.L.D.) Rules for the Design, Development, Verification, and Operation of Flight Systems (GSFC-STD-1000 Rev D, June 2008) will be applied.
I&T Assumptions - Process2 of 4 • Although it may occur elsewhere, the process of observatory flight hardware Integration is baselined at NASA GSFC, in Greenbelt, led by GSFC personnel, and conducted per GSFC directive 568-PG-8700.1.1B. • Structural verification model built and used for structural test to verify structure models, alignment process development, and deployment testing, w/o risking damage and contamination of flight structure. • Observatory environmental testing performed with no mass simulators, mockups, protoflight units etc. • Enables Test as you fly, demonstrates self compatibility
I&T Assumptions - Cost3 of 4 • Matrixing of I&T labor is successful, especially during Phase A through Phase C where the discipline teams are building up with respect to FTEs. • Most of the observatory I&T costs are for labor. The remaining observatory I&T costs are for other (e,g., facilities, GSE, materials, TDY, training, infrastructure, packaging, shipping). • Except for selected tests, all schedule and flow elements are based on labor rates of an 8-hour per day shift, 5-day work week and observance of Federal holidays • The deliverables to observatory I&T are complete staggered, and on time • In practice, at least 20% contingency is included in planning to “merge” I&T planning estimates with past project history to allow for retesting of failed components, delivery delays, unexpected shift work and other unplanned costs as are inherent in the implementation phase of the I&T process.
I&T Assumptions – Facilities & GSE4 of 4 • GSFC or other integration and test facilities are ready and available when needed • Identification of all Module- and Observatory-level test facilities and support off-site is complete and accurate. • Rigorous contamination control including special filtration, constant N2 mirror purge, continuous real time monitoring, scheduled cleanings and black light inspections. • Preserves science integrity. Must be considered in selection, configuration and operation of facilities, cost driver, schedule driver. • All GSE and materials slated for use at the observatory I&T site are identified. • All GSE slated for use at the launch site will be CCAFS-certified in advance, calibrated, and at hand
GSE Required for I&T effort1 of 3 • NOTE: Substantial amounts of GSE are required to support the integration effort. Much of this equipment will be developed and used at the subsystem level and be delivered with the flight hardware to I&T. Other equipment will be developed specifically for I&T use. • Only GSE identified in the following table as being provided by I&T is included in the I&T costs. The costs for all other GSE are assumed to be carried by the group identified in the column marked “Provider.” • The costs and development schedule of this equipment is not trivial. This list is not meant to be exhaustive or complete.