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SPICA / AIV&T issues Spacecraft test program & model philosophy (tentative plan) Feb. 19 2010 revised Nov. 19, 2009 1st draft by H. Matsuhara, N. Takahashi, T. Nakagawa SPICA Telescope Assembly (STA) 3m-class cooled telescope Monolithic Mirror No deployable mechanism Simple, Feasible, Reliable Smooth PSF Ceramic material (SiC) Essential for Coronagraph Herschel & AKARI Heritage SPICA: WFE 0.35μm, 5K (3.5m) AKARI: WFE 0.35μm, 6K (70cm) Herschel: WFE 6μm, 80K (3.5m) STA models & proposed delivery (tentative plan) STM (Structure Thermal Model) Proposed delivery : Oct. 2012 (beginning of 3Q of FY2012) AIT plan Integrated as PLM (STM) Thermal test at cold (@Tsukuba 13m chamber) Integrated into Spacecraft (STM) Spacecraft Mechanical Environmental test & Thermal Vacuum Test FM Proposed delivery : Jan. 2017 (beginning of 4Q 2016) STA Optical Performance test at cold (1) Date & duration: 1Q of CY2017, 1-2 months Place : 6m Space Chamber in Tsukuba Space Center Configuration IOB(FM)+STA(FM) Additional thermal sheild in the chamber Purposes: Optical performance evaluation of STA at <10K Multiple measurements are connected by the Stitching Method 4 STA Optical Performance test at cold (2) 2 LN2 Shroud GHe Shroud Flat-mirror STA ACF Cryo Sorption Pumps 5 Interfero meter 6 ACF 8 1 7 Gear Motor Turbo Molecular Pumps 5-axis stage Test Specimen Mount Table (with Shroud) 4 Anti-Vibration Table GHe 3 Pillar of Vacuum Vessel LN2 Independent Foundation 5 PLM Thermal Test at cold Purpose Date & Duration Evaluation of PLM cooling system performances STM: April 2013 FM: Dec. 2017, ~2months Method Additional shields in the existing 13m space chamber in Tsukuba Shields are externally lifted by mechanical coolers 6 SPICA AIV&T timeline (tentative) 7 Key issues for FPI AIV&T FPI’s system-level test plan should take account of the critical issues as below: (a) FPI is cooled to <5K with J-T coolers under extremely careful Spacecraft thermal design. (b) disturbance and interference from J-T coolers and AOCS (such as RW, gyro) (c) Co-operation with FPC-G to establish the pointing stability To assure high-sensitivity (low-noise) in orbit Interferences? Alignment? (d) Co-focus among FPIs (especially MIR’s) Since STA 2ry cannot be adjusted so frequently in orbit FPI Model philosophy Cold FPIs Minimum number of Models required for the system level test (in the previous page) is: FM (Flight Model) (& its spare) STM : structure thermal model CQM : cold qualification model Delivery date of FM: June 2016 (August 2016 at worst) in the proposed scenario. Warm Electronics Similar as above, except for the terminology (CQM PM (proto-model) Spacecraft DHS simulator(SpaceWire I/F) will be developed, and distributed hopefully before 2014 ( under discussion) STM (Structure Thermal Model) for FPIs Description Required Function Mechanical I/F specifications (including disturbance sources) is equivalent to that of FM Same mechanical I/F specifications to FM Nearly the same thermal I/F (TBD, for spacecraft(PM) thermal test) Equipped with thermometers, acceleration sensors for measurement of I/F environmental condition Simulate mechanical disturbance according to the system operation modes Proposed Delivery Oct. 2012 : before starting of assembly of PLM(STM) for the system Mechanical & Thermal Test CQM (Cold Qualification Model) for FPIs Description Required Function Nearly equivalent to FM incorporating with detectors operable at low-temperature expected in orbit Same thermal, mechanical, electrical I/F specifications to FM Equipped with detectors operable at low-temperature, with the same noise performance as that of FM Simulate heat-dissipation (load to J-Ts), mechanical disturbance according to the system operation modes Proposed Delivery Apr. 2015 : when the PLM(FM) is available for us to test the items (a), (b), & (c) in page 8. FPI: SPICA system test plan With STM: With CQM: Mechanical Environmental test & thermal test at cold at the PLM level Mechanical Environmental test & Thermal vacuum test at Spacecraft level Measure disturbance at FPI from J-T cooler/AOCS Cooling compliance test with J-T (PM) Evaluate effect of mechanical disturbances from J-T (PM) and AOCS simulator, Evaluate electrical interferences among FPIs, J-T, AOCS in the latter half of FY2015 With FM FPI evaluation at cold (optical & electrical) STA optical performance test at cold Thermal test at cold at PLM level 12 Focal Plane Instrument Assembly (FPIA) = IOB+FPI 2300 TOB:Telescope Optical Bench IOB: Instrument Optical Bench 13 FPI Evaluation at cold (1) Date & Duration: Place: 6m Space Chamber at Tsukuba Space Centre (tbd) Configuration: latter half of CY2016, 1-2 months IOB(FM dummy)+FPI(FM)+cooler(TBD)+FPI warm electronics (FM) (+STA Simulator..) Purposes: With all FM FPIs together, all functional, electrical & optical performance evaluation at cold (operating temperature in orbit) as well as interference test. Optical performance will be measures with a STA simulator. 14 FPI Evaluation at cold (2) IOB FPI FPI LHe Mech. cooler 15