1. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 1 Gamma-ray Large Area Space Telescope Status of the EM Vib Tests GLAST Large Area Telescope: GLAST Large Area Telescope: Tracker Subsystem INFN - Bari

2. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 2 Outline  Test strategies  First results  Panel vib plan: tests done!  Tray thermal plan: tests to be done  Tower vib plan: ok plan and procedure ready for TRR, fixture calibration done, tower test to be done  Tower thermal-vacuum plan: TBR  EM Matrix plan Reference LAT Documents: 1.LAT-MD-00408, LAT Instrument Performance Verification Plan 2.LAT-SS-00788, LAT Environmental Specification 3.LAT-TD-01005, Thermal Test Results on Thick Converter Mock-up Trays 4.LAT-TD-01249, Thermal Test Results for Pre-Engineering Model Trays 5.LAT-PS-01584, LAT Tracker Tray SSD Ladder Panel Assembly Procedure 6.LAT-TD-01004, EM Tray Vibration Test Plan 7.LAT-TD-01037, EM Tray Thermal Test Plan

3. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 3 EM Tray vib levels Frequency (Hz) ASD Qual Level (g 2 /Hz) ASD Accept Level (g 2 /Hz) ASD Launch Level(g 2 /Hz) 200.0260.0130.0065 20-50+6 dB/oct 50-8000.160.080.04 800-2000-6 dB/oct 20000.0260.0130.0065 Overall14.0 g rms 10.0 g rms 7 g rms Duration2 min1 min Random vibration Frequency (Hz) ASD WN Level(g 2 /Hz) Overall g rms Duration (min) 20 ÷ 200010 -4 0.451 White Noise Frequency range 20  2000 Hz Sweep rate2 oct/min Target Amplitude 0.5 / 0.25 g 0-pk Sine sweep

4. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 4 Tray vib set up Accelerometers position: Control: two mono-axial accelerometers positioned on two of the four L-shaped block TP1&TP2 Fixture: three mono axial accelerometers placed on a corner on one of the four L- shaped block TP6 Tray: one three-axial accelerometer in the middle TP5 Centrotecnica set up: - 1 LDS V864LT shake table - 2 fixtures - 9 read out channels - 4 trays/day test rate capability W side on the top

5. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 5 EM Tray vib sequence thrust axis StepDescription TestLevel 1Fixture, tray and accelerometers mounting 2Fixture calibration and tray resonance search Sine sweep0.25 g 0-pk 3Pre-random vibration White noise0.45 g rms 4Random vibration Launch 5Post/Pre-random vibration White noise0.45 g rms 6Random vibration Acceptance 7Post/Pre-random vibration White noise0.45 g rms 8Random vibration Qualification 9Post-random vibration White noise0.45 g rms 10Normal mode check Sine sweep0.25 g 0-pk 11Dismounting 12Test completion

6. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 6 EM Trays: some results (1) Sine sweep before/after randomRandom vibration + White noise Resonance search: 0 = 815 Hz, Q  51 Resonance check: 0 = 809 Hz, Q  49 Z accelerometer response X accelerometer response Y accelerometer response

7. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 7 Light ≈ 1000Hz ≈ 800Hz Heavy tray Mid tray EM Trays: some results (2) ≈ 660Hz

8. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 8 EM Trays: some results (3) “Watch-dog” Input-notched: 13.6 g rms Output-notched: 59.6 g rms Applied notching on qual ASD: output ≤ 16 g 2 /Hz (  Q=10) “Watch-dog” Heavy tray (TS05) Q=100 @ 660Hz  Output-expected: 140.4 g rms

9. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 9 All trays first mode › 500 Hz 530 EM Trays: summary Vib test pass criteria:  / < 5%  / < 2%

10. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 10 EM Tower vib levels Sinusoidal vibration Modal surveyRandom vibration: new level TKRAcceptance (g)Qualification (g) Lateral (X)  3.7  4.6 Lateral (Y)  3.7  4.6 Axial (Z)  6.8  8.5 Sine burst: quasi static test@25Hz Frequency range20  2000 Hz Sweep rate2 oct/min Input Amplitude0.15 g 0-pk Alarm Levels± 1 dB Upper Abort Level0.25 g 0-pk Lower Abort Level- 2 dB

11. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 11 Tower vib set up: Accelerometer. # Side- wall Tray #Location Read-out axis 1+X19 (top)+x, -y cornerx 2+X19 (top)+x, +y cornerz 3+X19 (top)+x, +y cornerx 4+X10Center of structural close-outx 5+X1 (bottom)+x, +y cornerz 6+X1 (bottom)+x, +y cornerx 7+Y19 (top)+y, -x cornery 8+Y10Center of thermal bossy 9+Y1 (bottom)+y, -x cornerz 10+Y1 (bottom)+y, -x cornery 11-X10Center structural close-outx 12-Y10Center of thermal boss planey 13-19 (top)Center of the top side of the top trayz 14-1 (bottom)Bottom side of the bottom tray near the +x, -y cornerx 15-1 (bottom)Bottom side of the bottom tray near the +x, +y cornery 16-1 (bottom)Center of the bottom side of the bottom trayz Accelerometer locations

12. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 12 Accelerometers location

13. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 13 Fixture calibration

14. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 14 EM Tower vib sequence X,Y,Z axis For each axis Run #Test DescriptionFrequencyComments 1Modal surveyInput: 0.15 g (20 – 2000 Hz) 2Sinusoidal vibration5 – 50 HzQual level 3Modal surveyInput: 0.15 g (20 – 2000 Hz) 4Random Vibration (-6 dB)Input 20 – 2000 Hz1 min duration 5Modal surveyInput: 0.15 g (20 – 2000 Hz) 6Random Vibration (- 3 dB)Input: 20 – 2000 Hz1 min duration 7Modal surveyInput: 0.15 g 20 – 2000 Hz 8Random Vibration (Full level)Input: 20 – 2000 Hz1 min duration 9Modal surveyInput: 0.15 g (20 – 2000 Hz) 10Random Vibration (Full level)Input: 20 – 2000 Hz2 min duration 11Modal surveyInput: 0.15 g (20 – 2000 Hz) 12Sine burst (1/4 level)25 Hz5 cycles 13Sine burst (1/2 level)25 Hz5 cycles 14Sine burst (full level)25 Hz5 cycles 15Modal SurveyInput: 0.15 g (20 – 2000 Hz)

15. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 15 EM matrix ItemQuantityQuantity to testSine burst (staticequivalent acceleration)Random Vibe + modalsurveySinusoidal vibrationFunctionalThermal CycleThermal balanceThermal VacuumTest site Panels24 Qual Z axis Centrotecnica (vib) Live Trays 51Qual Z axis QualCentrotecnica (vib) Alenia (thermal-vac) Dummy Trays 195 vib 19 ther Qual Z axis QualCentrotecnica (vib) INFN Perugia (in Terni) (thermal) Tower11Qual X,Y,Z Qual X,Y,Z Qual X,Y, Z QualItaly

16. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 16 Test plans & procedures: EM open items Tower vib test FEM from Hytec Warning and abort levels Discussion of non-conformances and procedure variations Add a Sinusoidal test levels at protoflight level? Add a step …

17. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 17 Flight units New random level: Qual tower  Protoflight tower Trays tower A vib level? Trays flight vib level?

18. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 18 Towers: random levels Tower A Old levels (general GEVS levels) New levels Qualification (12.3 grms, 2 min) Workmanship (6.8 grms, 1 min) Trays for tower A Qualification (14 grms, 2 min) Qualification ?? (14 grms, 2 min) Towers 1-16 Acceptance (8.7 grms, 1 min) Workmanship (6.8 grms, 1 min) Trays for towers 1-16 Acceptance (10 grms, 1 min) Acceptance ?? (10 grms, 2 min)

19. GLAST LAT ProjectGSFC, October 2003 LAT-PR-0XXXX 19 Tray assembly&test sequence Tray factory (panels)Vibration testLadder factory Tray assembly: ladders and MCMs on trays Thermal cyclesStacked cosmic rays*Electrical testFast electrical test*Tower assembly * Live trays Vacuum bakeout Plyform Centrotecnica Roma G&A G&A Mipot