SPICA / AIV&T issues Spacecraft test program & model philosophy (tentative plan)

1. SPICA / AIV&T issuesSpacecraft test program & model philosophy (tentative plan) Feb. 19 2010 revised Nov. 19, 2009 1st draft by H. Matsuhara, N. Takahashi, T. Nakagawa

2. ＳＰＩＣＡ Telescope Assembly (STA) • 3m-class cooled telescope • Monolithic Mirror • Ceramic material (SiC) • No deployable mechanism • Simple, Feasible, Reliable • Smooth PSF • 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)

3. 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)

4. STAOptical 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

5. STAOptical Performance test at cold (2) Flat-mirror STA 5-axis stage

6. PLM Thermal Test at cold • Purpose • Evaluation of PLM cooling system performances • Date & Duration • 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

7. SPICA AIV&T timeline (tentative)

8. 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) • To assure high-sensitivity (low-noise) in orbit • (c) Co-operation with FPC-G to establish the pointing stability • Interferences? Alignment? • (d) Co-focus among FPIs (especially MIR’s) • Since STA 2ry cannot be adjusted so frequently in orbit

9. 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)

10. STM (Structure Thermal Model) for FPIs • Description • Mechanical I/F specifications (including disturbance sources) is equivalent to that of FM • Required Function • 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

11. CQM (Cold Qualification Model) for FPIs • Description • Nearly equivalent to FM incorporating with detectors operable at low-temperature expected in orbit • Required Function • 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.

12. FPI: ＳＰＩＣＡ system test plan • With STM: • 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 • With CQM: • 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

13. Focal Plane Instrument Assembly (FPIA) = IOB+FPI TOB：Telescope Optical Bench IOB: Instrument Optical Bench 2300

14. FPI Evaluation at cold (1) • Date & Duration: • latter half of CY2016, 1-2 months • Place： • 6m Space Chamber at Tsukuba Space Centre (tbd) • Configuration: • IOB(FM dummy)＋FPI(FM)＋cooler(TBD)＋FPI warm electronics (FM) (＋STASimulator..) • 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.

15. FPI Evaluation at cold (2) IOB FPI FPI LHe Mech. cooler